lifespan development case study

9.1 What Is Lifespan Development?

Learning objectives.

By the end of this section, you will be able to:

Define and distinguish between the three domains of development: physical, cognitive and psychosocial
Discuss the normative approach to development
Understand the three major issues in development: continuity and discontinuity, one common course of development or many unique courses of development, and nature versus nurture

My heart leaps up when I behold A rainbow in the sky: So was it when my life began; So is it now I am a man; So be it when I shall grow old, Or let me die! The Child is father of the Man; I could wish my days to be Bound each to each by natural piety. (Wordsworth, 1802)

In this poem, William Wordsworth writes, “the child is father of the man.” What does this seemingly incongruous statement mean, and what does it have to do with lifespan development? Wordsworth might be suggesting that the person he is as an adult depends largely on the experiences he had in childhood. Consider the following questions: To what extent is the adult you are today influenced by the child you once were? To what extent is a child fundamentally different from the adult he grows up to be?

These are the types of questions developmental psychologists try to answer, by studying how humans change and grow from conception through childhood, adolescence, adulthood, and death. They view development as a lifelong process that can be studied scientifically across three developmental domains—physical, cognitive, and psychosocial development. Physical development involves growth and changes in the body and brain, the senses, motor skills, and health and wellness. Cognitive development involves learning, attention, memory, language, thinking, reasoning, and creativity. Psychosocial development involves emotions, personality, and social relationships. We refer to these domains throughout the chapter.

Connect the Concepts

Research methods in developmental psychology.

You’ve learned about a variety of research methods used by psychologists. Developmental psychologists use many of these approaches in order to better understand how individuals change mentally and physically over time. These methods include naturalistic observations, case studies, surveys, and experiments, among others.

Naturalistic observations involve observing behavior in its natural context. A developmental psychologist might observe how children behave on a playground, at a daycare center, or in the child’s own home. While this research approach provides a glimpse into how children behave in their natural settings, researchers have very little control over the types and/or frequencies of displayed behavior.

In a case study, developmental psychologists collect a great deal of information from one individual in order to better understand physical and psychological changes over the lifespan. This particular approach is an excellent way to better understand individuals, who are exceptional in some way, but it is especially prone to researcher bias in interpretation, and it is difficult to generalize conclusions to the larger population.

In one classic example of this research method being applied to a study of lifespan development Sigmund Freud analyzed the development of a child known as “Little Hans” (Freud, 1909/1949). Freud’s findings helped inform his theories of psychosexual development in children, which you will learn about later in this chapter. Little Genie, the subject of a case study discussed in the chapter on thinking and intelligence, provides another example of how psychologists examine developmental milestones through detailed research on a single individual. In Genie’s case, her neglectful and abusive upbringing led to her being unable to speak until, at age 13, she was removed from that harmful environment. As she learned to use language, psychologists were able to compare how her language acquisition abilities differed when occurring in her late-stage development compared to the typical acquisition of those skills during the ages of infancy through early childhood (Fromkin, Krashen, Curtiss, Rigler, & Rigler, 1974; Curtiss, 1981).

The survey method asks individuals to self-report important information about their thoughts, experiences, and beliefs. This particular method can provide large amounts of information in relatively short amounts of time; however, validity of data collected in this way relies on honest self-reporting, and the data is relatively shallow when compared to the depth of information collected in a case study. An example of comprehensive survey was the research done by Ruth W. Howard. In 1934, she obtained her doctorate by surveying 229 sets of triplets, the most comprehensive research of triplets completed at the time. This pioneering woman was also the first African-American woman to earn a PhD in psychology (American Psychological Association, 2019).

Experiments involve significant control over extraneous variables and manipulation of the independent variable. As such, experimental research allows developmental psychologists to make causal statements about certain variables that are important for the developmental process. Because experimental research must occur in a controlled environment, researchers must be cautious about whether behaviors observed in the laboratory translate to an individual’s natural environment.

Later in this chapter, you will learn about several experiments in which toddlers and young children observe scenes or actions so that researchers can determine at what age specific cognitive abilities develop. For example, children may observe a quantity of liquid poured from a short, fat glass into a tall, skinny glass. As the experimenters question the children about what occurred, the subjects’ answers help psychologists understand at what age a child begins to comprehend that the volume of liquid remained the same although the shapes of the containers differ.

Across these three domains—physical, cognitive, and psychosocial—the normative approach to development is also discussed. This approach asks, “What is normal development?” In the early decades of the 20th century, normative psychologists studied large numbers of children at various ages to determine norms (i.e., average ages) of when most children reach specific developmental milestones in each of the three domains (Gesell, 1933, 1939, 1940; Gesell & Ilg, 1946; Hall, 1904). Note that while they are still in use, the terms "normal" and "normative" often require deeper consideration, and some researchers and practitioners aim to avoid them. Psychologists often consider typical or "normal" signs in order to diagnose when a child may need examination or support. Although children develop at slightly different rates, we can use these age-related averages as general guidelines to compare children with same-age peers to determine the approximate ages they should reach specific normative events called developmental milestones (e.g., crawling, walking, writing, dressing, naming colors, speaking in sentences, and starting puberty).

Not all normative events are universal, meaning they are not experienced by all individuals across all cultures. Biological milestones, such as puberty, tend to be universal, but social milestones, such as the age when children begin formal schooling, are not necessarily universal; instead, they affect most individuals in a particular culture (Gesell & Ilg, 1946). For example, in some countries children begin school around 5 or 6 years old, but other countries, children often enter school at an advanced age, or have limitations or interruptions in their education. For example, UNESCO estimates that nearly 244 million of the world's school-aged children do not attend school (Antoninis, 2022).

To better understand the normative approach, imagine two new mothers, Louisa and Kimberly, who are close friends and have children around the same age. Louisa’s daughter is 14 months old, and Kimberly’s son is 12 months old. According to the normative approach, the average age a child starts to walk is 12 months. However, at 14 months Louisa’s daughter still isn’t walking. She tells Kimberly she is worried that something might be wrong with her baby. Kimberly is surprised because her son started walking when he was only 10 months old. Should Louisa be worried? Should she be concerned if her daughter is not walking by 15 months or 18 months?

Link to Learning

The Centers for Disease Control and Prevention (CDC) describes the developmental milestones for children from 2 months through 5 years old. After reviewing the information, take this Developmental Milestones Quiz to see how well you recall what you’ve learned. If you are a parent with concerns about your child’s development, contact your pediatrician.

Issues in Developmental Psychology

There are many different theoretical approaches regarding human development. As we evaluate them in this chapter, recall that developmental psychology focuses on how people change, and keep in mind that all the approaches that we present in this chapter address questions of change: Is the change smooth or uneven (continuous versus discontinuous)? Is this pattern of change the same for everyone, or are there many different patterns of change (one course of development versus many courses)? How do genetics and environment interact to influence development (nature versus nurture)?

Is Development Continuous or Discontinuous?

Continuous development views development as a cumulative process, gradually improving on existing skills ( Figure 9.2 ). With this type of development, there is gradual change. Consider, for example, a child’s physical growth: adding inches to height year by year. In contrast, theorists who view development as discontinuous believe that development takes place in unique stages: It occurs at specific times or ages. With this type of development, the change is more sudden, such as an infant’s ability to conceive object permanence.

Is There One Course of Development or Many?

Is development essentially the same, or universal, for all children (i.e., there is one course of development) or does development follow a different course for each child, depending on the child’s specific genetics and environment (i.e., there are many courses of development)? Do people across the world share more similarities or more differences in their development? How much do culture and genetics influence a child’s behavior?

Stage theories hold that the sequence of development is universal. For example, in cross-cultural studies of language development, children from around the world reach language milestones in a similar sequence (Gleitman & Newport, 1995). Infants in all cultures coo before they babble. They begin babbling at about the same age and utter their first word around 12 months old. Yet we live in diverse contexts that have a unique effect on each of us. For example, researchers once believed that motor development follows one course for all children regardless of culture. However, child care practices vary by culture, and different practices have been found to accelerate or inhibit achievement of developmental milestones such as sitting, crawling, and walking (Karasik, Adolph, Tamis-LeMonda, & Bornstein, 2010).

For instance, let’s look at the Aché society in Paraguay. They spend a significant amount of time foraging in forests. While foraging, Aché mothers carry their young children, rarely putting them down in order to protect them from getting hurt in the forest. Consequently, their children walk much later: They walk around 23–25 months old, in comparison to infants in Western cultures who begin to walk around 12 months old. However, as Aché children become older, they are allowed more freedom to move about, and by about age 9, their motor skills surpass those of U.S. children of the same age: Aché children are able to climb trees up to 25 feet tall and use machetes and other tools (Kaplan & Dove, 1987). As you can see, our development is influenced by multiple contexts, so the timing of basic motor functions may vary across cultures. However, the functions themselves are present in all societies ( Figure 9.3 ).

How Do Nature and Nurture Influence Development?

Are we who we are because of nature (biology and genetics), or are we who we are because of nurture (our environment and culture)? This longstanding question is known in psychology as the nature versus nurture debate. It seeks to understand how our personalities and traits are the product of our genetic makeup and biological factors, and how they are shaped by our environment, including our guardians, peers, and culture. For instance, why do biological children sometimes act like their parents—is it because of genetics or because of early childhood environment and what the child has learned from the parents? What about children who are adopted—are they more like their biological families or more like their adoptive families? And how can siblings from the same family be so different?

We are all born with specific genetic traits inherited from our biological parents, such as eye color, height, and certain personality traits. Beyond our basic genotype, however, there is a deep interaction between our genes and our environment: Our unique experiences in our environment influence whether and how particular traits are expressed, and at the same time, our genes influence how we interact with our environment (Diamond, 2009; Lobo, 2008). This chapter will show that there is a reciprocal interaction between nature and nurture as they both shape who we become, but the debate continues as to the relative contributions of each.

The Achievement Gap: How Does Socioeconomic Status Affect Development?

The achievement gap refers to the persistent difference in grades, test scores, and graduation rates that exist among students of different ethnicities, races, and—in certain subjects—genders (Winerman, 2011). Research suggests that these achievement gaps are strongly influenced by differences in socioeconomic factors that exist among the families of these children. While the researchers acknowledge that programs aimed at reducing such socioeconomic discrepancies would likely aid in equalizing the aptitude and performance of children from different backgrounds, they recognize that such large-scale interventions would be difficult to achieve. Therefore, it is recommended that programs aimed at fostering aptitude and achievement among children with lower socioeconomic status may be the best option for dealing with issues related to academic achievement gaps (Duncan & Magnuson, 2005).

Children from low-income households perform significantly more poorly than their middle- and high-income peers on a number of educational variables: They have significantly lower standardized test scores, graduation rates, and college entrance rates, and they have much higher school dropout rates. There have been attempts to correct the achievement gap through state and federal legislation, but what if the problems start before the children even enter school?

Psychologists Betty Hart and Todd Risley (2006) spent their careers looking at early language ability and progression of children in various income levels. In one longitudinal study, they found that although all the parents in the study engaged and interacted with their children, parents with middle- and high-income status interacted with their children differently than parents with lower-income status. After analyzing 1,300 hours of parent-child interactions, the researchers found that middle- and high-income parents talk to their children significantly more, starting when the children are infants. By 3 years old, children from higher-income households knew almost double the number of words known by their peers from lower-income households, and they had heard an estimated total of 30 million more words than the children from low-income households (Hart & Risley, 2003). And the gaps only become more pronounced. Before entering kindergarten, children with higher-income status score 60% higher on achievement tests than their peers with lower-income status (Lee & Burkam, 2002).

There are solutions to this problem. At the University of Chicago, experts are working with low-income families, visiting them at their homes, and encouraging them to speak more to their children on a daily and hourly basis. Other experts are designing preschools in which students from diverse economic backgrounds are placed in the same classroom. In this research, children with lower socioeconomic status made significant gains in their language development, likely as a result of attending the specialized preschool (Schechter & Byeb, 2007). What other methods or interventions could be used to decrease the achievement gap? What types of activities could be implemented to help the children of your community or a neighboring community?

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Lifespan Development: A Psychological Perspective - Fourth Edition

(38 reviews)

Martha Lally, College of Lake County

Suzanne Valentine-French, College of Lake County

Last Update: 2023

Publisher: Martha Lally, Suzanne Valentine-French

Language: English

Formats Available

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Learn more about reviews.

Reviewed by Michael Shaughnessy, Professor, Eastern New Mexico University on 1/16/24

Comprehensiveness rating: 5 see less

This is a VERY comprehensive book, integrating historical, medical and psychological information as it relates to human growth and development. That being said at 496 pages- it is really a graduate level book- as undergraduates would be overwhelmed with it and its comprehensiveness. It is up to date and chock full of tables and figures and pictures and is well organized and rich and robust with depth.

Content Accuracy rating: 5

From what I have seen the book is accurate, and while I did not read every word of every page of this 496 page book- what I have read seems on target and relevant and unbiased.

Relevance/Longevity rating: 5

Very timely and relevant- one notices the mention of COVID and it's impact on learning and the growth and development of the human organism. Artificial intelligence will be integrated into this 10 chapter book relatively quickly. At first, when I saw 10 chapters, I thought this would be a superficial summary type of book but it is surprisingly an indepth very comprehensive book- one that might fit into an honors class.

Clarity rating: 5

Clarity is good- but this book would need to be a text for a 16-week course- to allow students to read and reflect and absorb the material.

Consistency rating: 5

Logical rational and reasonable---but the length is overwhelming- students might intially be drawn to the pictures charts and graphs- but this is a graduate level text for a graduate level class- in which the graduate students have plenty of time to read and review and reflect.

Modularity rating: 4

This is a ten-chapter book- but it really delves into each chapter extensively. I was initially happy to see the 10-chapter organization- but each of these chapters is rich and robust and in depth-. I suppose that students could be told to skim over the historical and medical parts and just glance at the charts and graphs and figures- but this is a THICK book- 496 pages- and it deserves a full semester. I would NOT recommend this for a summer class.

Organization/Structure/Flow rating: 5

It is easy to reflect on the organization as it covers the human development from birth to death - and does so comprehensively. This is a book for reflective scholars- who want to stop and think about and in class- to discuss all of the issues comprehensively covered.

Interface rating: 5

Charts, graphs, figures---are all clean and neat---font could be larger in SOME places- but BOLD is used for terms and headings- and this is nicely organized.

Grammatical Errors rating: 5

Readable, enjoyable, conversational----but time has to be allocated for a real reading of this 496 page tome.

Cultural Relevance rating: 5

The authors seem to have worked on this- and I have seen a balance here- and I have no concerns or objections.

As I have already mentioned,----this is a book that deserves a full semester---and should not be used in a 4-week summer class or any 8-week approach. This book deserves the time to absorb, think about and reflect on the material that is interwoven with theory and factual knowledge and information. This is a rich robust, but thick challenging book for serious graduate students who really do want to learn more not just about human growth and development- but the human condition !

Reviewed by Kelli Rogers, Assistant Professor Practice, University of Texas at Arlington on 12/12/22

Comprehensiveness rating: 4 see less

This text examines how biological, psychological, and social factors shape people’s lives from conception to death, covering various stages of development and a number of theories relates to these stages. However, there is need for further discussion of atypical development and the influence of various social, cultural, and environmental contexts. There is no glossary, which would be helpful for students who prefer to print the text.

Content Accuracy rating: 4

The content parallels other text on lifespan development and course curricula. However, more contemporary research would increased its accuracy. Detailed discussions of risk and protective factors relative to each of the stages of development would provide a more comprehensive perspective. In addition, other issues of diversity (besides just socioeconomic background and culture) should be described.

Relevance/Longevity rating: 4

This text contains relevant information, however, there are several older references. While this may be appropriate for theoretical and historical discussions of human development, it fails to include updates in science and technology that significantly influences development. In addition, the inclusion of case vignettes would improve relevance and engagement. The text is written and arranged in such a way that necessary updates will be relatively easy and straightforward to implement.

This text is well-organized and easy to read, which makes it ideal for undergraduates. The learning objectives could be more concisely written, as there are several sets of topic-specific learning objectives in each chapter.

Consistency rating: 4

The text appears to be presented in a consistent manner, with regard to terminology and framework. However, the degree of depth to which theories and concepts are covered varies. For example, there are fewer theories discussed in chapters middle adulthood through late adulthood, which may be a reflection of current literature.

Modularity rating: 5

The text consists of 10 chapters, organized by developmental stages and can be easily reorganized and realigned for a variety of course modalities. The text is also easily and readily divisible into smaller reading sections that can be assigned at different points within the course

Organization/Structure/Flow rating: 4

The topics in the text are presented in a logical, clear fashion and the layout remain consistent across all chapters. However, some chapter lack a smooth transition between subsections and topics.

The text is free of significant interface issues. The table of contents and external links embedded within the chapters are navigable. The charts and images are readable.

I did not noticed any grammatical errors or issues.

Cultural Relevance rating: 4

I would have appreciated more content on issues of diversity and how this significantly impacts various stages of development. Ageism was limited to experiences in late adulthood ad fails to discuss ageism in adolescence. Case study examples of a variety of backgrounds, disabilities and abilities, religions/spirituality, etc., would improve cultural sensitivity and inclusivity. More diverse images and the inclusion of studies of nonwhite populations would be beneficial.

Overall, I found this text to be very comprehensive in covering all of the developmental stages and major theories of development. While the majority of the content is consistent with other texts, supplemental reading materials, documentaries, case vignettes, etc., are necessary to improve relevance, accuracy, and inclusiveness.

Reviewed by Michael Slavkin, Assistant Professor of Psychological Services and Counseling, Marian University on 5/31/22

Each chapter is organized around a developmental level. Pertinent theories and concepts are covered. Details are strong and material is well discussed. read more

Each chapter is organized around a developmental level. Pertinent theories and concepts are covered. Details are strong and material is well discussed.

No accuracy issues were evidenced. The text is error-free and no bias seems to exist. Relevant information and up-to date references.

The textbook is relevant, providing current information that links with the current research in the field. There is a clear arrangement as the text is tied to areas of development. The fact that there are 10 chapters makes the text fairly straightforward to implement over the course of a term.

No clarity issues were found. The text is written in a clear style, and provides good content with limited jargon. Those terms that are new are highlighted for student ease (no glossary is included, but bolded words are used for new terms).

The text is internally consistent, using a clear organizational scheme. There is no issue with framework, and material could be supplemented easily.

The text is divided into 10 chapters, which could be aligned to different course management systems easily. The text is not overly self-referential. It can be organized and aligned with articles or materials relatively easily.

The topics in the text are organized well. The material is clearly stated, and presented relatively easily for review.

No navigation problems or distorted in any way. The text was displayed well.

Clear text with no grammatical issues.

The book does an exemplary job of sharing up-to-date material that supports a strong multicultural and diverse background. Details about exceptionalities, neurodiversity, and cultural/social sensitivity are included.

The text by Martha Lally and Suzanne Valentine-French is a solid overview of lifespan development. Appropriate for psychology, sociology, education, and human services; this would be a strong textbook for use in a variety of programs. Well organized and developed.

Reviewed by Joshua Smith, Psychology Instructor, Dodge City Community College on 2/25/22

This book is well laid out and covers all of the major areas of the lifespan development. The book is hits on all of the major concepts and theories that I would want to teach in an introductory or intermediate lifespan development course. The book does not contain a list of key terms and definitions at the end of the chapters or a glossary. An index at the end of the text would also be helpful.

Content in the text is consistent with other introductory development textbooks. Historical and theoretical information is accurate and contemporary examples are beneficial. The text presents information that is consistent with psychological theory and supported by research in a way that appears free of any overt bias.

The text was updated in 2019, but still contains several older references. Depending on your teaching goals (e.g., theoretical foundations vs. modern applications), the addition of more recent works could be beneficial. Instructors might need to supplement with recent research in some areas. There have been some updates from previous versions, such as the inclusion of social media and its influences on adolescents.

Clarity rating: 4

The text is clear and should be relatively easy for the average undergraduate student to understand. Major terms and concepts are generally defined in context as you read each chapter, but definitional content could be better. A glossary would help with this. It may occasionally be challenging for students to differentiate major theories or concepts from examples and elaborations on those concepts.

The table of contents is very informative and aligns clearly with the layout of each chapter. Chapter layouts are consistent and easy to follow, making the text very easy to navigate. An index at the end of the text would be helpful for students looking for concepts that are not major chapter or sections headings.

The organization and presentation of chapters follows the unfolding of the human lifespan, so reordering the text is not likely to be necessary. Within each chapter, the text is easily divisible into smaller sections for reading or teaching.

Chapters are clear and logically organized. Presentation of chapter topics follows the unfolding of the human lifespan which is appropriate for a lifespan course. Some instructors might choose to reorder subtopics and sections within a chapter which could easily be done.

Interface rating: 4

The interface is smooth. You can click on chapter titles or subsections from the expanded table of contents to be linked directly to that section of the text. However, navigation within each chapter would be more smooth if the bookmark function was used in the left navigation bar to provide point and click navigation to each chapter and section as you read.

I did not notice any grammatical errors during my review.

There is a nice, if small, section on culture and development in chapter one, but this is not detailed. In several areas, the text touches on culture and diversity, and explores their impact on development. For example, the text brings up cultural influences on cognitive development and education, gender and gender identity, parenting behaviors, marriage practices, and many other areas. However, as with many introductory texts the predominant focus is on white-western culture which serves as the normative comparison point for other groups.

I would use this text for my introductory course in developmental psychology.

Reviewed by Elbert Davis, Assistant Professor, Marshall University on 12/17/21

This is a very in-depth textbook on lifespan development. The authors follow the lifespan from pre-birth to death. The theories are introducted in the first chapter, and are again discussed in the relevant developmental stage in future chapters.... read more

The content of the textbook relies on factual information, providing references at the end of each chapter. Author bias was not observed. Errors were not evident.

This textbook would be easy to update. The chapters are broken into many different sections, which is reflected in the table of contents. While lifespan development is not a new concept, the authors included information on transgendered persons, which is not something usually discussed. That was refreshing to see.

The authors introduce jargon and new terminology by highlighting in purple. They also do a great job in breaking up text by using graphics and tables.

The chapters are arranged using the same basic framework, which makes it easier on the reader to know what to expect.

The authors use extensive subheadings to break up the material, as well as images and tables.

The topic of lifespan development makes it easier for organization. The authors started with pre-birth and discussed the various stages of development, inlcuding infancy, childhood, and adulthood, until death.

There was nothing confusing or distorted in the book. Navigation was easy. The subheadings in the table of contents were clickable, making it easy to navigate.

No graamatical errors were evident throughout the book.

Cultural diversity is woven into the chapters, as well as students with learning disabilites.

Reviewed by Lisamarie Bensman, Assistant Professor, Windward Community College on 12/12/21

This text includes all major areas of development that I would expect to find in a developmental text. The index at the beginning of the text is useful for a quick overview of what is in each chapter and can be used to jump to specific sections. There isn’t a glossary, which has its positives and negatives. Glossaries can be super helpful in reminding students of what terminology means, but they can also provide students with an oversimplified idea of those concepts, so for me a glossary is not a deal breaker.

The content in the text is accurate and provides a solid introduction to development. I was particularly pleased with how the authors presented Freud, as they appropriately acknowledged his lasting contributions to development, as well as the limitations of his work, and did so without his presenting his unsupported, unscientific theory of psychosexual development followed by the usual disclaimer. Avoiding this standard but very flawed way that many developmental texts handle Freud set a tone early on that the authors thought carefully about the validity of the content that they included and would present only the most accurate, scientifically supported information. That trend appears to have continued throughout the text (with a few exceptions, please see comments on relevance).

The majority of the content appears to be as current as can reasonably be expected for any text and, in some places, even more current than would be expected (for instance, when I selected this text in 2019 it already included a small section on children in detention centers at the southern US border and the impact separation and stress has on children, as well as the APA’s opposition to family separations). There are a few places, particularly in regards to pregnant individuals in the second chapter and in regards to gender identity that language could be more inclusive and better reflect current research and understanding, but even then, the language and understandings used are not that out of date nor different from how many developmental texts approach these issues (I’m not saying this standard approach is a good thing, merely a common issue).

The writing in this text is clear and easy to follow. The style is a bit more formal than would be my ideal for my particular students, but it’s not overly formal in an off-putting way. The syntax is appropriate for college students of all levels.

The text is consistent in the framework and terminology used. As a developmental text, it follows a standard organizational format for each chapter (after the beginning two foundational chapters and minus the final chapter on death and dying). The authors clearly, consistently, and appropriately reference back to the same theories and concepts throughout each chapter (adding new developmental concepts and removing old concepts, as appropriate). They provide enough context each time that a past theory/concept is presented to remind students what the students already know without giving so much context that students feel like they are re-reading the same information over and over again.

The chapters in the text are a bit lengthy because they cover all areas of development within the chapter’s developmental time period. If desired, smaller sections within each chapter could be assigned using page numbers. But there’s only one link for the whole book, as opposed to separate links per chapter or section, so if you were going to assign sections within each chapter separately, you’d have to first figure out the page numbers and then students would have to navigate to those sections. This isn’t the end of the world, just like navigating to each chapter isn’t the end of the world, but it might be something you or your students find annoying. As this is a developmental textbook, I wouldn’t suggest doing the chapters or sections out of order (I’d say the same for any developmental text).

This text is well organized. It has one chapter per developmental time period with each chapter progressing from physical development to cognitive development and ending with social development. Putting all three areas of development into one chapter does make the chapters long, but students seem to think they have less reading this way than with development textbooks that do three chapters per developmental time period (i.e. one chapter per area). Within each chapter, the topic order makes sense and follows naturally.

Interface rating: 3

The interface for this book is okay. The text and images flow well together. There are no confusing breaks/blank spaces or distorted images. That being said, it’s not the easiest text to navigate. If you know what page you want or remember to use the table of contents at the beginning of the text (which does allow you to jump directly to a section), you’re all set. But if you’re in a chapter and want something else in that chapter, it’s a scroll till you find it or use ctrl-F a lot type situation. On the left-hand side of the .pdf are thumbnails of the pages, but a linked table of contents would be easier. That way, the sections and order of the chapter could be seen at a glance and, if linked, one could jump directly to the desired section.

There are no large grammatical errors of note. For the most part, the text reads well/easily. There are a few hiccups here and there, but nothing overwhelming, nor do the small issues happen enough to be off-putting or undermine confidence in content.

Cultural Relevance rating: 3

Based on the reviews, I expected more discussion of culture than I found in this text. Even the ‘issues in development’ section in chapter 1 is missing the question of whether development is universal or particularistic, an overarching question addressed in most developmental classes. That being said, there are some sections throughout the text that do mention the impact of culture. In a related vein, as far as diversity goes, while there is some diversity mentioned, there isn’t as much diversity as needed to reflect real life. Even the images selected skew highly Caucasian in many sections. This lack of diversity made the text less relevant to my students who are extremely diverse and might struggle to see themselves in the images and descriptions given.

Generally, I am satisfied with this text. I am currently finishing my fourth semester teaching with it. Students have reported that they find the book easy to read and engaging enough. I typically describe it as a solid text without the bells and whistles of the new for-purchase textbooks and that my students as a group get more out of this text that they can afford to read than they would out of a flashy, interactive text that few of them can afford to buy. I do recommend this text to other instructors.

Reviewed by Mary Ann Woodman, Adjunct Professor, Rogue Community College on 12/8/21

The content material in this book is very easy to read and well organized. It provides a comprehensive look at the stages of human growth over time including theoretical, methodological and historical approaches to lifespan development. Chapter 1: Introduction to Lifespan Development Chapter 2: Heredity, Prenatal Development, and Birth Chapter 3: Infancy and Toddlerhood Chapter 4: Early Childhood Chapter 5: Middle and Late Childhood Chapter 6: Adolescence Chapter 7: Emerging and Early Adulthood Chapter 8: Middle Adulthood Chapter 9: Late Adulthood Chapter 10: Death and Dying Each chapter presents physical development, cognitive development, and psychosocial (or social and emotional) development.

The information is historically accurate, unbiased and without error. It includes a balance of history and contemporary theories and concerns. The information in this text appears accurate, error-free, and unbiased. There is a great deal of content in each chapter from birth to death and all stages in between. Within each category of development, physical, cognitive, and psychosocial development is covered along with stories and examples to support the theories. It also contains links to other resources for students to consider as they study.

The book was completed in 2019, so it is up to date, written and arranged in a way that provides for updates in an easy and straightforward manner. An instructor can easily supplement the material with current issues relevant to the material presented in each stage of human development. The bibliography at the end is also helpful.

The authors writing style is lucid, easily accessible with college level terminology. The learning objectives make it easy for student outcomes and instructor assessment. It would be beneficial to include a glossary and make certain the PDF meets standards of accessibility according to federal legislation.

Each chapter is laid out in a developmental structure with sub-headings that make it consistent in framework. There are no inconsistencies in terminology. The bold vocabulary and italic definitions are a desirable feature and the print size very readable.

The text is organized well and additional material could be added without presenting disruption to the reader. Because the content is already 468 pages, a bit much for college students to absorb in one term, it might be wise to condense some of the material if new content is later added.

Birth to death in a linear fashion is the mark of a book focused on Lifespan Development and this one offers physiology, psychology, sociology and research to support the content. It is well organized in chapters with clear subheadings, and very easy to follow.

The images, graphs, charts and visuals support and enhance the written material very well. Many students are visual learners therefore, this component adds a great deal for understanding the concepts. There are no places that distract or confuse the reader.

There are no grammatical errors in this book.

Most of the chapters include cultural sensitivity of race, ethnicity, and gender concerns. There is a fair amount of information focused on family diversity, religious populations, gender roles and inclusivity.

It will be a gift to offer this textbook at our College as the current cost of textbooks has risen to levels quite unaffordable by our students. Much appreciation to the authors for their incredible efforts in providing this resource for Lifespan Development Courses.

Reviewed by Jeongwoon Jeong, Instructor, Fort Hays State University on 10/20/21

The overall text covers comprehensive ideas including basic and advanced concepts of theories. It would have been better if the text included index or glossary. read more

The overall text covers comprehensive ideas including basic and advanced concepts of theories. It would have been better if the text included index or glossary.

The text content is mostly standard and accurate.

The text content is mostly up-to-date and relevant to each subject with different resources.

The text is well written and is to understand; however, it could have better if the text is more clearly separated between subjects and theories

The text is internally consistent in terms of terminology and framework. They also well included tables and images for each theory or framework

I can say that the text has a high readability by including smaller reading sections.

The topics in the text are well organized by theories and others but some sections are not clear whether they are listed headings or sub-headings.

The text included appropriate images but I would recommend to have more vibrant images.

The text contains no grammatical errors.

Since diversity is very important in our society, I hope that the text included more about cultural perspective in each chapter and theories.

Reviewed by Keonya Booker, Associate Professor, College of Charleston on 9/15/21

This textbook analyzes the human lifespan from birth until death. Each chapter includes a discussion about the physical, cognitive, and psychosocial changes that can be expected at every developmental stage. The expanded table of contents lists all sub-headed sections, but a clear distinction between the three aforementioned categories would have been useful. Terms are in bold print and defined for the reader. The addition of a glossary would be helpful for students who wish to have particular terms organized in one place.

Overall, the textbook is accurate. There are few errors that would significantly change the meaningful content of the book. As an introductory textbook, the major theories of development are presented correctly and without bias.

This textbook juxtaposes classic developmental theory (e.g., Sociocultural, Constructivism, Behaviorism) that will not change, with more recent information that may have to be updated. For example, in the late adulthood chapter the leading causes of death in the wake of COVID will likely have to be revisited. It should be easy to make these revisions. Since the last update was in 2019, another version could address this.

The writing was clear and without filler. Jargon is left to a minimum and examples are provided to help the reader understand complex terms. At times there is an overwhelming amount of statistical references, which can result in a sea of parenthetical percentages that may be hard for students to move through.

Each lifespan stage has a section devoted to physical, cognitive, and psychosocial development. The textbook is consistent with respect to its terminology and framework. A list of fully cited references are provided at the conclusion of each chapter.

In its current state, the textbook is in a PDF format. While the table of contents provides page numbers, it would be preferable to have a more reader-friendly searchable function such as hyperlinked headers, or another way to go to a specific part of the text. As it stands right now, the reader has to seek and scroll. Also, each chapter is very dense, some at more than 40 pages. In a typical twice or thrice weekly class schedule, an instructor may have to assign sections and specific pages at a time.

As this is a developmental psychology textbook, the authors presented the human lifespan in a logical fashion. The physiological and social implications of each developmental stage are addressed.

Most of the images added to the reading experience; however, a few were distorted and unclear. Replacing these images would be helpful. The figures and tables illuminated important topical ideas and research findings.

Grammatical Errors rating: 4

There were a handful of grammatical errors, some of which were within a bolded, defined term. Another thorough editing of the textbook could eliminate this issue.

The authors presented the qualities of the human experience from multiple cultural perspectives. Beyond racial and gender diversity, attention was paid to LGBTQ+ communities, neurodivergent populations, and those who are differently abled. Research was presented that explored how humans make sense of their worlds in a diverse set of circumstances and from a unique identity perspective. The inclusion of images that depicted various multicultural groups was an important component as well.

Thank you to the authors for providing an open source alternative to a traditionally published textbook. I appreciate the time and effort it took to complete such a large project.

Reviewed by Cebrail Karayigit, Assistant Professor, Pittsburg State University on 4/22/21

This book is comprehensive, and includes chapters on each stage of the lifespan. The book covers not only cognitive domain, but also biosocial and psychosocial development, involving continuity and change. The book also analyze different developmental events from the perspective of the major theories of development (e.g. Erikson, Kohlberg). This book also provides a thorough understanding of the timing and sequence of development throughout the lifespan.

The content of this is accurate and consistent with most developmental levels. However, there are few things in emerging adulthood section that I do not believe are fully up-to-date (e.g. emerging adulthood has been proposed as a new life stage between 18-29 in recent literature). Emerging adulthood and Early Adulthood could be covered separately and in different chapters.

The book explains how research contributes to the understanding of development. Although information included is mostly relevant to each developmental level, I do not see any focus on how use of social media plays a crucial role in adolescents' and emerging adults' lives.

The information presented is written very clearly, and the book is easy to follow.

The book has a consistent format and structure. The chapters has good internal consistency.

Each chapter could include a separate domain (e.g. cognitive, biosocial, and psychosocial/emotional), so it would make it easy to focus on specific topics across different developmental levels.

While the book has a consistent and logical structure, it would be helpful if the subsections in each chapter were arranged according to specific domain such as cognitive, biosocial, and psychosocial aspect.

Information is presented in a way that makes it easy to read and navigate. The book contains a lot of figures, graphs, and seems like a good fit with the online format.

No major grammatical errors were detected.

Although few chapters focus on diversity (e.g. chapter 1 and 8), it would make it more effective if each chapter included a section that attempt to analyze different developmental events from the perspective of non-Western perspective.

Reviewed by Dr. Charlene Moore-Peterson, Adjunct Professor, Aiken Technical College on 3/16/21

This book covers all areas effectively as it relates to the subject of Lifespan. read more

This book covers all areas effectively as it relates to the subject of Lifespan.

Accuracy is error and is unbiased.

Content in this book is updated and easy and straightforward to implement effectively.

This book provides adequate context.

Great consistency.

This book is easily readily divisible; broken down inyo section is quite helpful.

Well organized.

The text is free of interface issues.

Little to no grammatical errors.

The text is not culturally insensitive and is not offensive in anyway. Culturally appropriate.

Reviewed by Emily Healy, Assistant Professor, Bunker Hill Community College on 2/9/21

This textbook provides a comprehensive look at human growth and development over the lifespan. It begins with an introductory chapter, which looks at theoretical approaches to studying lifespan development, different methodological approaches to... read more

Chapter 1: Introduction to Lifespan Development Chapter 2: Heredity, Prenatal Development, and Birth Chapter 3: Infancy and Toddlerhood Chapter 4: Early Childhood Chapter 5: Middle and Late Childhood Chapter 6: Adolescence Chapter 7: Emerging and Early Adulthood Chapter 8: Middle Adulthood Chapter 9: Late Adulthood Chapter 10: Death and Dying

Each chapter and corresponding period of development is treated from different perspectives: physical development, cognitive development, and psychosocial (or social and emotional) development.

The information in this text is accurate, error-free, and unbiased. As a survey course, this book is tasked with covering a wide amount of information of the entire lifespan. The book looks at issues of heredity, prenatal development, birth, infancy and toddlerhood, early childhood, middle and late childhood, adolescence, emerging and early adulthood, middle adulthood, late adulthood, and death and dying. Within each category of development, physical, cognitive, and psychosocial (social-emotional) development is considered. Furthermore, each period of development includes special topics and categories that are more pertinent to those periods of development. For example, in the chapter on late adulthood, issues of retirement, neurocognitive disorders, elder abuse, and substance use disorders specifically in the elderly populations are treated. By contrast, in the chapter on adolescence, special topics include sexual development, eating disorders, and teenage drivers.

This book is likely to retain a high score in relevance in the coming decades. While it provides a wealth of information specific to each stage of lifespan development, the information is no so specific as though it will become obsolete or outdated quickly. This textbook provides a solid foundation upon which instructors and educators may build in relevant examples from current events. For example, in the chapter on middle and late childhood, while the topic of physical development is discussed and special topics of sports and childhood obesity are treated, an individual instructor can bring in information that is relevant and pertinent to the specific population in which he/she/they are teaching.

This text is written clearly, in an accessible manner, providing both context and working definitions for any technical terminology. The textbook introduces students to technical terminology used in the field of human growth and development in a scaffolded manner, where new concepts are introduced in appropriate context, are then defined. and the concepts are used in examples in order to improve reader comprehension. Each section of the chapter begins with the learning objectives for that particular section. The text utilizes headers and subheaders to clearly denote information organization. Vocabulary words are bolded and set in the text in purple, and definitions are in italics.

The textbook is organized in a consistent manner. Each chapter begins with an overview. Each section of the chapter contains a text box including learning objectives for that section. Each chapter (apart from the first introductory chapter) treats the subject matter from three broad domains or dimensions: 1. Physical development 2. Cognitive development 3. Psychosocial (social-emotional) development

Within the chapters, consistent formatting of headers and subheaders are used. It is a well-organized and highly navigable text overall, which is student-friendly.

On the whole, this text is easily divided into sections. Chapters do not run over into each other, as each chapter begins on a new page. The text also makes use of a consistent, predictable format, which makes it more predictable for the reader. The only drawback to the text that I have found with regard to its modularity is that it would be helpful if the three approaches (physical development, cognitive development, and psychosocial development) were also set apart. For my own classes, I treat physical and cognitive development on one day (or one week), and psychosocial development on another day (or week), and it is not readily divisible into these sections.

Overall, the organization of this text is clear and predictable. Each chapter is clearly listed, with topics clearly defined. Each section contains a set of learning objectives for that section. In addition, the chapters are organized in a repeating manner, then adding in topic-specific information for that particular stage of development.

The text is easily navigable, and is easily exported as a PDF (in the event that the instructor wishes to break the textbook down chapter-by-chapter for students, such as in an online learning environment where different topics are treated on a week-to-week basis).

The text is very culturally sensitive. Pictures in the text depict a wide array of diverse racial, ethnic, and religious populations (for example: BIPOC, Muslim individuals, etc.). Furthermore, discussions of special topics within chapters are treated from a multitude of perspectives. For example, in the section on religion, a wide variety of faith traditions are treated, rather than singling out one perspective. Furthermore, in the section on family units, different formulations of families (including step- and blended- families, as well as LBGT families) are included.

Reviewed by Jacqueline McMillion-Williams, Adjunct Professor, Bunker Hill Community College on 1/31/21, updated 2/1/21

For a course on developmental psychology, this text provides appropriate coverage of all areas of the lifespan. The table of contents provides an effective index in both short and long form. Key words are bold and defined within the text, but... read more

Accurate information about theory and application with diverse perspectives of the lifespan. Theory presented within a historical context with examples of life lived in a variety of circumstances that influence development.

There is a clear timeline of theory formation, historical context, and application to current society and with recent data. The arrangement of the text, with clear citations and reference information at the end of each chapter allows data to be easily located and updated. This is also true of the use of current slang; reflective of the time and society the text is written within, but also easy to locate and update.

From my perspective, the audience for this book is students and as such, a benefit of this book in comparison to those I have used in the past, is the use of common and approachable language. There is an appropriate use of jargon so the reader can place it in context. Although the text is clearly academic, it tells a clear story about development that engages the reader.

From the beginning, there is a clear framework of development for the reader to follow. Contents of each chapter and use of terminology stays consistent with the framework.

Authors divide the content of the textbook into sections that are logical for a comprehensive overview of the lifespan. Content is easy to divide into weekly readings or modules for student consumption and learning. Teachers could choose to assign in the original order or rearrange content by preference. Simultaneously the sections can be pulled out to be used a supplements for study in other courses on the lifespan such as early childhood, child psychology or adolescence and adult. You could also choose to restructure content to provide individual overviews of each theory.

Authors present topics in a logical sequence as chapters and subtopics are sections of each chapter. This makes the text easy to follow and annotate.

The textbook does not have any interface issues. It has appropriate headings to divide sections. Images and charts are clearly visible in color and black & white. Images are in appropriate locations that provide illustration of information. Alignment with text is complimentary.

I did not locate any grammatical errors in the text.

Text includes culturally relevant and sensitive examples of a variety of backgrounds (race, ethnicity, and sexual orientation) as well as about various aspects of biological, psychological and social influences on normalized development in a manner that may challenge students to rethink what is normal.

My use of this text with students is just beginning. Initial adoption occurred based on a recommendation from other faculty. Overall, the text is more up to date and culturally diverse than past texts I have used for similar and the same course. I would have liked some supplementary materials, but given the electronic format of the text, I have not found it difficult to create my own.

Reviewed by Meagan Docherty, Assistant Professor, Bowling Green State University on 12/15/20

This book is comprehensive, and includes chapters on each stage of the lifespan, as well as an introductory chapter with information on the lifespan perspective, theories, and research. Each chapter includes the major developmental changes and tasks associated with physical, cognitive, and socioemotional development. The table of contents is very detailed, and provides information on subheadings within each chapter.

This textbook is more accurate than others I've looked into using. It provides information on historical research and theory, while also providing a more contemporary perspective, and indicating when findings may be culture-dependent.

I think the content generally appears to be up to date, and includes more contemporary perspectives and recent research findings.

This book is written in a clear, simple style that I think would work well for undergraduate classes. New terms are introduced and explained clearly.

The book appears to be consistent in its approach and framework, including concepts covered and terms used.

With maybe a few exceptions, the text is generally broken up into several subheadings, making it easy to use certain sections on their own or reorganize material if needed.

I think overall the book is organized very well. Other lifespan psychology books tend to break chapters up into subsections for physical, cognitive, and social and emotional development, and it's my impression that undergraduate students appreciate that distinction, so it may help for a later edition of this book to adopt that organization.

Overall I think the book is laid out very well, but some of the charts and images appear to be low quality or dated. I like that there are links to sources embedded in chapters, but overall it does not have the same production quality that undergraduate students may be used to with current e-books.

I did not notice any grammatical errors in my reading of the book.

Overall I think the book does a good job of being inclusive and highlighting different cultural perspectives while being sensitive and appropriate.

I like the material covered in the book, and I think it would provide a good amount of breadth and depth for an undergraduate lifespan course. I think if the production quality was even higher, it would make the book even easier to adopt.

Reviewed by Amy Clinard, Assistant Professor, Bunker Hill Community College on 12/14/20, updated 12/18/20

The Table of Contents itemizes lifespan development just in terms of the stages of the lifespan (infancy, early childhood, etc.) and does not further itemize based on domains which many other textbooks do (physical, cognitive, psychosocial). Although the full table of contents does provide an exhaustive list of specific topics covered within each of those lifespan stages, it might have been better to have those topics itemized by domains.

I very much appreciated the level of accuracy and the unbiased nature of this textbook. It is clear that the authors were deliberate in integrating multiple diverse perspectives into their work. I have not found any major content errors.

This textbook is notably up-to-date and contains many timely, current and important conversations that are not always found in textbooks. It would seem that any necessary updates will be easily implemented as a result.

This textbook is written in a way that is clear, accessibly, and ELL friendly. It clearly identifies, defines and explains psychological jargon and technical terms in a way that is easily understood by the reader.

The text is exceptionally consistent with terminology and framework.

Due to the fact that this textbook only contains a few chapters (based on the stages of the lifespan such as infancy, early childhood, etc.), and is not broken down further into developmental domains (physical, cognitive, psychosocial growth), it can make it slightly challenging to identify and assign smaller reading assignments without referencing specific page numbers.

The topics presented within this textbook flow nicely, and are organized in a logical manner for the reader.

There are no interface issues within this text such as navigation issues, distortions of images, etc. I would add that some of the images included within this textbook are slightly rudimentary (black and white, with limited detail or visual interest) and may benefit from some more interesting components.

There are no grammatical errors within this text.

I would say that this is a major strength of this textbook. In my experience, many other textbooks contain a limited amount of perspectives and/or inclusion of diverse ideas. This particular book is intentional in terms of including diverse perspectives, local AND global issues, and is relevant and meaningful to all students as a result.

Reviewed by Joshua Becker, Professor of Psychology, Greenfield Community College on 6/30/20

The text itself is comprehensive, with each topic organized into logical and interesting sub-topics. The sub-topics are written comprehensively in easy-to-digest paragraphs. There is no glossary or index, however. read more

The information in this text is accurate, current, and relatively bias-free. Good (brief) section in Early Childhood on transgender kids, for example.

This text has a good balance of grand theories and current research. It will (like all texts) require continual revising as new theories emerge and new areas of focus become important for developmental psychologists.

The writing is clear and understandable.

Good internal consistency!

This is a strength of this text. Each subsection can be used on its own, or part of the whole.

Overall, the text is well organized, though I think I would prefer a text that has more layers of organization. This text has 10 chapters, each with numerous sub-headings, but without clear delineations between domains of development.

I did enjoy the interface - though this is essentially one long PDF document, which may be confusing or problematic for some students.

Nice writing!

The text includes weaves in topics related to several lenses of identity, including race, class, sexualities, and gender identity. It does not challenge, however, the enduring structures of oppression in the field of psychology and society at large - though this is probably considered outside the scope of developmental psychology.

I enjoyed the text! I would consider adapting it if I could find ancillary materials.

Reviewed by Kevin Duquette, Assistant Professor, Bridgewater State University on 6/22/20

Very clearly laid out with ten chapters ranging from prenatal to death. Table of contents acts also as an index of sorts, with specific topics within each stage clearly defined and page numbers provided. Could benefit from a glossary (either at the end of each chapter or at the end of the text as a whole) and/or separate index for concepts that are present throughout multiple chapters.

An overall comprehensive view of development with special consideration for culture and diversity. Text also discusses how views have changed over time (e.g., in relation to intellectual disabilities; gender roles, etc.), and uses the most current terms. Text also provides information on many developmental theories (as opposed to pigeonholing information to few), and continually spirals back to these topics to reinforce them. A few small errors (e.g., “tabula rosa” instead of “tabula rasa”, pg. 16), but by and large information is up to date, and clearly explained.

All information is up to date, and uses current citations. Authors also did a great job with citing and providing sources as well so that readers can find additional information on topics from the primary sources. In addition to current parenthetical citations, the writers provide context to let the reader know when the data were taken, which allows a more informed understanding of the numbers provided. Authors show data trends over time that will be easy to update as newer data are published.

One area where there could be additional relevant information would be in regards to substance use, and the recent legalization of marijuana across U.S. states and Canada, and how this legalization may affect understanding and interventions related to marijuana and other substance use.

Writing is very accessible, and clear. Jargon terms are defined as part of the text and the flow of the book as a whole is logical. Main topics (i.e., developmental theories) are revisited and applied to specific life stages with relevant examples to connect to larger themes.

Major concepts are revisited in each chapter, and examples for application of knowledge are given. Further, the formatting itself is consistent, leading to an overall clean and intuitive look. Authors are also consistent with the use of discussion questions for each chapter.

Very well organized. Great use of headings, subheadings, bold, italics, color, and other formatting to break up ideas into intuitive sections. The chapters are broken up logically based on developmental periods. Could have benefited from additional focus specifically on early adolescence considering the importance of this stage of life (relative to others—similar to how the text broke up childhood into early ‘childhood’, and ‘middle & late childhood’)

Clear organization throughout. Good use of boxes, figures, graphs, etc. to enhance understanding and draw readers’ attention to important concepts or illustrations. Logically sequenced chapters and sections.

Very well-organized and good use of images/charts to enhance understanding. Text provides links to images, graphs, references for further reading, which enhances the interactivity of the text. Text would benefit from the ability to “jump” to chapters or sub-sections by clicking on that particular section in the table of contents.

Aside from the aforementioned “tabula rosa” being used instead of “tabula rasa” (p.16), this book reads well and is grammatically sound.

Shows appreciation and consideration of the effect of culture and intersectional identity on development. Provides international perspectives on development as well. The only criticism would be that the vast majority of the images used are of white people.

Solid text. Rivals books that are $100+.

Reviewed by Sandra Gilliland, Associate Professor, Louisiana State University of Alexandria on 4/20/20

This 468 page book covers all of the major stages and domains of development. The book begins with a detailed overview of the field of lifespan development and then goes into great depth on the common issues and areas of interest for each major... read more

The book appears to provide information from various perspectives allowing the student/reader to apply critical thinking to evaluate each topic.

This book was published in 2017, the majority of references are less than 10 years old. The topics are covered with several recent examples but also uses many of the historically popular studies that will remain relevant (for example Harlow's work on attachment).

This was actually my favorite part of the book. I found it very easy to read and feel as though my students would as well.

The book builds on some of the most reputable theories in lifespan development (Piaget, Erikson, Vygotsky).

Modularity rating: 3

I like that each stage of development is covered in separate chapters but it also results in very long chapters. For example chapter 3 is 44 pages long. That is a lot for students to digest so I would need to assign page numbers instead of chapters.

I like the breakdown of chapters into the developmental stages.

The book downloaded as a free PDF, no problems navigating.

No issues with grammar were noted.

Text and images appears to represent a wide arrange of different cultures.

The length of this book is a little intimidating but the content is excellent.

Reviewed by Masami Takahashi, Professor, Northeastern Illinois University on 4/5/20

This is a very comprehensive Lifespan Developmental Psychology textbook (465 pgs). It covers not only psychology but also a fair amount of biology as well, and almost any other topis I can think of including relatively up-to-date research findings. However, one may say that it is good for neither one thing nor the other. Although comprehensive, this book lacks details in theory and data for upper level Developmental Psychology courses for our Psych majors. The book simply scratches the surface of many topics. On the other hand, there is simply too much information for our Gen Ed Human Development. What this means is that the instructors are required to work quite a bit before adopting it for a particular course, at least initially (e.g., finding supplemental readings for our majors, selecting small portions of this textbook appropriate for our Gen Ed students, etc.).

It is accurate for the topics it covers, but the discussions are often limited in details for the Psych majors.

Content is relatively up-to-date. However. with any textbook with cutting-edge research evidence, it is inevitable that that part of the book will require further editing in the near future.

It is clearly written and readable for any level of undergrads.

I noticed several sections with duplication (i.e., cut/paste) that needs editing

For those instructors who are adopting a part of this book (e.g., easy sections for Intro Developmental), it would be helpful if the subsections in each chapter were numbered (2-1, 2-2, etc.) so that they can be specified in the syllabus.

Organization/Structure/Flow rating: 2

I like the fact that the References are provided not at the end of the book but immediately after each chapter. This allows the readers an easier access to the references if needed. Personally, however, I prefer a topic by topic (rather than chronological) arrangement of the chapters.

There are lots of Figures (mostly photographs from public domains) throughout the book that do not have any caption. I couldn’t tell what these pictures were for.

Good. Readable.

It includes a fair amount of cross-cultural studies

Having presented pros and cons above, would I adopt this book? Yes, I would for my Gen Ed course. That means after thoroughly reading this book, I have to handpick those sections that are general enough for the freshman/sophomore students, specify the pg numbers in syllabus, and align the contents with the exams that I already have for the course.

Reviewed by Linde Althaus, Psychology Instructor, Minnesota State University System on 3/8/20

This book covers all of the age groups covered in a lifespan class, but consolidates some age groups to lengthy chapters. read more

This book covers all of the age groups covered in a lifespan class, but consolidates some age groups to lengthy chapters.

The book appears to be straight-forward and accurate. Several topics could use up-dating and it surprised me that it was last updated in 2019.

The photos seemed dated and some of the topics could be refreshed, but it did not impact my perception of the book as a whole.

Topics were clearly written and were approachable to a reader.

The writing and terminology appears to be consistent throughout the text.

The chapters were long and I feel like it may be difficult to divide into modules. I'm not sure how I would assign the readings in a fully online class if I adapted this text.

This is a book organized from birth to death, which is how I like to teach Lifespan. Someone who teaches a topical approach would struggle using this text.

You have to scroll through the text to find your page. There are not easy ways to jump to various sections of the text. I wanted to read particular sections that I feel are my areas of expertise and I found it cumbersome.

What I read appears correct and well-written.

Some of the pictures are culturally diverse, but I would like more examples and descriptions of other cultures within the text.

I appreciate that this book is available, but I am hesitant to adopt it at the moment. If it was updated, made easier to navigate and more cultural diversity was added, I would definitely switch.

Reviewed by Pamela L. Parent, Associate Professor (Adjunct), J. Sargeant Reynolds Community College on 1/14/20

The text was comprehensive and well-planned. Addresses major concepts and theories with numerous online links to facilitate further inquiry. read more

The text was comprehensive and well-planned. Addresses major concepts and theories with numerous online links to facilitate further inquiry.

Accurate content with good coverage of material. Commendable addition of inclusion of some “nontraditional” areas in developmental psychology.

Good use is made of numerous and diverse live links allowing readers to access various resources.

Written in a clear and coherent manner with some excellent examples. Content was presented in a manner that made it useful to varying levels of learners.

Chapters are well-structured and organized in a clear manner throughout.

Chapters contain logical sections with subheadings. Developmental Psychology lends itself well to a chronological format as used in this text.

Well-organized with consistency in addressing domains. Chapter sections well-segmented.

This text worked well with the online format. Contains numerous helpful graphs, diagrams, etc.

Grammatical errors were not apparent however a few spelling errors that one would hope would have been caught on review - “constructivitst’ and “constrctivist” in the same sentence cluster.

This book consistently incorporated attention to diversity. The unique influences of various cultures on developmental stages was well-addressed.

A comprehensive textbook that works well as an OER. I am intrigued by the possibility of using this as my primary text.

Reviewed by Elizabeth Becker, Senior Instructor II, Eastern Oregon University on 1/4/20, updated 1/15/20

The text covers a wide range of topics related to development, including current trends and issues. read more

The text covers a wide range of topics related to development, including current trends and issues.

The text is accurate and includes a large number of references. It also includes important critiques of major theorists.

The structure of this text will allow it to be easily updated and continue to address important trends and issues.

Educational Psychology texts are often written with dense academic language that makes it a challenge for students to easily process and understand. This OER is written in a way that makes the information more accessible to students and will help keep their interest.

There is a consistent format and structure used throughout the text.

While the overall organization of the text is through chronological age, each chapter addresses many of the same topics in a way that would make it easy to focus on specific topics across different ages/chapters.

The text follows a consistent and logical organization.

The material is presented in a fashion that makes it easy to read and navigate.

No major grammatical errors or patterns were detected.

This text specifically addresses cultural differences related to the topics at hand in a way that is respectful and will help anyone working with a variety of cultures in the classroom.

Reviewed by Amy Hammond, Associate Professor/Dept Chair, Centenary College of Louisiana on 12/30/19

Very comprehensive! All the major concepts and ideas are addressed, although sometimes briefly (as is necessary in a lifespan text). read more

Very comprehensive! All the major concepts and ideas are addressed, although sometimes briefly (as is necessary in a lifespan text).

On the whole, the content is accurate and consistent with most developmental texts. There are elements in the pre-natal development section (particularly around teratogens) that I do not believe are fully up-to-date and provide inaccurate or misleading information.

Content is highly relevant to the topic. While there are some topics that some would consider “supplemental” throughout, there is enough variety that individual instructors can tailor inclusion of these materials as they desire.

Material is presented in a clear and coherent manner throughout the text.

The structure within in chapter reflects consistent approaches to the material. The writing and thoughtfulness is consistently strong throughout.

Organization and structure lend themselves to including or excluding various elements as one chooses. Major sections are easily identified and segmented.

The overall organization is very good for a chronological developmental text. Within chapters, there is a consistent organization of physical, then cognitive, then psychosocial issues and within these sections, when relevant, consistencies in the order of presentation of theories and concepts.

Learning Objectives in each chapter were clear, if exclusively at the lower levels of Bloom’s Taxonomy. I found the use of headings within chapters to be difficult to follow. It wasn’t always easy to see which sections where sub-sections of which ideas. Overall, this text is less visually “fun” than the big publisher versions, however, it is full of colorful photos, relevant graphs and diagrams.

Excellent! This text is easy to read, but is still written in an appropriate manner for lower-level college students.

There is excellent coverage of ideas for a United States audience relevant to US-centric concerns (for example, there are very good sections on LGBTQIA issues). However, mention of topics outside a US context are somewhat thin (especially in the first half of the text). To be fair, this reflects weaknesses in the field more generally (which are slowly being rectified). There is more comprehensive consideration of cross-cultural issues in later chapters. The prenatal development section felt somewhat maternal-blaming. While there were some explicit mentions that environmental factors were important, there was strong implication that most things which could go wrong were the “fault” of the mother. Nothing was explicitly stated in this way, but I felt there was too little explicit and implicit acknowledgement of the randomness that can sometimes cause less-than-ideal outcomes during pregnancy and birth.

I am grateful to our colleagues who have worked to put together this excellent resource! And in particular that you have chosen to make it available in a way that invites ongoing use/changes/updates! It allows me to use the many, many, MANY wonderful elements and tweak the few things that are not quite my personal pedagogical approach. I anticipate adopting this text next year!

Reviewed by Sara Fier, Professor, Minnesota State University System-Southwest Minnesota State University on 12/30/19

The book provided good coverage of developmental psychology concepts. There was no index or glossary included, although the fact that the book is in an electronic format makes this less problematic than for a hard copy book. read more

Comprehensiveness rating: 3 see less

The book seemed to present information accurately and presented multiple theories/perspectives on topics without getting too technical/detailed.

The book covers developmental psychology historical information and developmental basics well. More recent research is incorporated as well. The book's format seems to allow for updates to be easily made.

The book is easy to understand. In some cases illustrative examples help explain concepts that may be new to the reader. The reader would benefit from the use of additional examples.

The book's internal consistency is good, with chapters being organized in a similar format.

Developmental psychology allows for ease of modularity, and this text uses a chronological lifespan format.

The book was organized in the typical developmental psycology chronological format and then further broken down within each chapter by developmental domain: physical, cognitive, social. That was easy to follow. As future editions of the book lead to revisions within each domain, domain-specific organization and transitions can be reconsidered.

Navigation of the book was easy and seemed to work well in the electronic format. No display issues were noted.

Grammatical Errors rating: 3

The book had grammatical/typographical errors comparable in number to published textbooks.

A variety of examples were provided related to diversity of race, ethnicity, and background. Authors should continuously strive to enhance incorporation of these topics into books.

I appreciate the authors making this book available. I look forward to using it as a devopmental psychology text.

Reviewed by Diane Bordenave, Associate Professor, SUNO on 11/9/19

The text covers lifespan development content from birth until death. There is an Table of Contents with chapter sections and page numbers for reference. read more

The text covers lifespan development content from birth until death. There is an Table of Contents with chapter sections and page numbers for reference.

I found no grammatical errors, bias or inaccurate content.

The content of the textbook should become more and more relevant as the country recognizes the importance of understanding and responding to the needs of an aging generation of baby boomers. For the most part, content has been more focused on early childhood and infant development. When comparing the content to older lifespan development textbooks, I did not see many issues where changes in a short period of time were necessary for updating the text. For the most part, issues of development covered here have remained relatively unchanged over time. Particularly in an introductory survey course, more in-depth analysis of changes and consequences such as those resulting from science or technology, are not expected here but can be further explored in graduate or higher level specialized courses on a topic.

The textbook is written at a level appropriate for the students at my HBCU, many of whom are first generation college students. Terminology, when used, is defined. Figures and Tables assist in interpreting the prose.

The terminology and framework in the text is internally consistent and is particularly suited to a lifespan approach. It helps to understand the continuity of life from birth to death and how earlier stages of development impact later ones when the terminology and framework are consistent.

I would have preferred that the text was divided into more chapters than 10 to better align with a typical semester of 15 weeks. Students tend to understand and work better on a chapter by chapter basis than on subsections in my experience.

After a well written introduction, the text presented the chapter is a logical fashion that followed the normal human developmental process from birth to aging/death.

I was able to both view the textbook online and download it and make a copy. I had no interface, navigational or display feature problems in either context. I intend to offer this textbook in an online format.

I found no grammatical errors, and I am a stickler for that in the academic setting.

I teach at an HBCU with mainly non-traditional students so cultural sensitivity is important to me in choosing content. The cover of the textbook is of a diverse family which is immediately welcoming. In the chapter are other culturally diverse images such as in Figure 1.1.

I have adopted this book for my Spring 2020 course CDFS 303 Lifespan Development in the Family. I am happy to give the students the benefit of not having to purchase an expensive textbook, which many of them were unable to do, and still benefit from the readings. I have recommended this book to my colleagues as well.

Reviewed by Sarah McEwan, Assistant Professor, Marian University on 11/4/19

This text addresses all aspects of human growth and development that I cover in my course. read more

This text addresses all aspects of human growth and development that I cover in my course.

This text is accurate up to its published date, 2017.

Published in 2017, so relatively up to date, but there's always few opportunities for updates here and there.

This text is quite user friendly and quick to read.

The text has solid internal consistency.

This book covers all the basics, but just the basics. This text does not contain a lot of additional fluff that other texts contain.

This text was well organized.

No issues with navigation.

I found no grammatical issues.

The text does a fine job covering the basics, but the field of psychology in general has a ways to go to become inclusive.

I chose this text for an accelerated course- I needed a book that accurately and concisely covered all my key concepts, which this did. However, this text did not have as many opportunities/ asides to provide further reading for students interested in specific areas as I have seen in other textbooks. If you are looking for fluff, this is not your textbook. However, I intend on continuing to use this text in my accelerated classes, as it was perfect for a quick overview that my students could manage in a short amount of time.

Reviewed by Allie Chroust, Assistant Professor, East Tennessee State University on 4/21/19

The textbook covers human development across the lifespan. It is presented in the chronological framework. Each chapter provides an in-depth look at that stage of development. However, there is no glossary of key terms or index. Students would... read more

To the best of my knowledge, the information presented within the textbook is accurate. The one area for improvement in relational to accuracy would be the updating some of the sections to use more inclusive terminology (e.g., Children with Disabilities, p. 176).

The textbook is was last revised in 2017. I did come across one or two content areas that should have been updated for the latest edition (e.g., Box 2.3 on p. 50--the Tennessee Law has since been changed; Figure 1.18 p. 2006--it would be very easy to update the years on the basic figure as the years do not relate to any specific study it is simply a schematic of research design).

The textbook is written at a level that lower-level undergraduate students can understand.

Terminology and framework is consistent throughout textbook.

The text is divided into 10 chapters. There are subsections within each chapter if the instructor wishes to break up readings assignments into smaller chunks.

Chronological presentation of human development.

Textbook is easy to navigate within your PDF reader. Tables and Figures are clear. Each hyperlink I tested within the textbook worked properly.

No to minimal grammatical errors.

The textbook does an adequate job describing that human development occurs in variety of contexts, one of those contexts being culture. However, the textbook could provide a more in-depth description of the impact of culture on various developmental concepts. For example, the textbook frequently states, "in some cultures, ...." but, more often then not, textbook does not describe the different patterns of behavior or specify what culture is being referenced.

It is great to have an open textbook aimed at lifespan development however I would like to see a few improvements to make it more competitive against the ebooks for-profit publishers are providing: 1) glossary of terms and/or definitions in the margins 2) improved figures and creation of figure captions 3) inclusion of examples of applications of concepts that show students how the information can be directly applied to various careers 4) hyperlinks within the text--for example if students click on one of the learning objectives at the beginning of the chapter, they are taken to the section of that chapter that addresses that specific objective. 5) inclusion of reading comprehension questions for students to check themselves on before moving on to next section.

Reviewed by Patrick Smith, Associate Professor, Thomas Nelson Community College on 3/21/19

The comprehensiveness of the textbook is interesting, as there are only ten chapters. In other words, the authors pack a great deal of information into each chapter. This book covers all of the requisite topics for an introductory or survey... read more

This is an introductory level textbook, so specific research found in higher level courses would be missing. For the most part, this text covers the basics well, and any inaccuracies are negligible and can be overcome with good discussion.

The thoroughness of the coverage, which is a strength, makes this text very relevant to get a good discussion of actual human development going.

This textbook is very easy to read and follow. Any technical terms and theoretical concepts are well defined and illustrated within an applicable context.

There is no real individual psychological perspectives evident here beyond the basic introduction to this context of human psychology. For this reason, all areas of the human lifespan get fair coverage and presentation.

With a lifespan development course, it is easier to present material that can be discussed as physical, cognitive, or socioemotional. This textbook is divided by stage of life alone. For this reason, it may be difficult to separate chapters into smaller reading sections easily.

The text follows a nice, logical pathway through the human lifespan with a pretty strong connection between stages of development.

Technically, the presentation of the textbook comes without flaw.

There is no consistently evident problem with grammatical errors.

There is a pleasant focus on diversity and inclusion in both the text and the illustrations. There is some attempt to apply the principles discussed beyond the dominant culture of America, without this being forced and artificial.

I would highly recommend this textbook for an introductory, 200-level developmental psychology course. It hits all the right points and is engaging enough to stimulate some good class discussions.

Reviewed by Natalie Danner, Assistant Professor, Western Oregon University, Open Oregon Educational Resources on 3/20/19

This textbook is VERY comprehensive and covers lifespan development from prenatal development to death and dying. There is a very detailed Table of Contents; making it easy to find age groupings, theories, or concepts in development. There is no glossary, which would be helpful to find mentions of a specific term. Overall this textbook covers a great deal of material, without delving into the topic of atypical development.

The developmental theories and definitions were accurate.

Most of the content is still current, and the publication dates for this text is 2017. However there is an emphasis on Howard Gardener's Multiple Intelligence theory in Chapter 5 which has much research against it currently. Rather in the field we now advocate for more of a Universal Design for Learning (UDL) approach or a multi-sensory/hands-on approach to learning. Neither of which are mentioned in the text.

This text would be easy to read and accessible for an undergraduate course in child/adolescent/lifespan development.

Yes, this text is internally consistent.

I plan on using only several chapters of this textbook for a focus on child development ages 3-elementary; chapters 1, 4, and 5. These chapters do make sense on their own and will work as good content for my child development course. However, I wished that the theories that were mentioned, a few in each chapters, either could have all been combined in one chapter, or were easier to pull for individual readings for an online course.

Other than the theories, the book moves in a linear fashion from prenatal development to death and dying. Theories are interspersed in a variety of chapters.

It was easy for me to navigate through the textbook. Images and charts were clear.

This textbook used accurate grammar and writing conventions.

Cultural Relevance rating: 2

The book does not mention cultural diversity, cultural bias, diversity of children and families, and other key topics needed in a child development text. Supplemental material will be needed to focus on this subject.

Reviewed by Laura Lawn, Adjunct Faculty, Chemeketa Community College on 3/5/19

On the whole, the book is very comprehensive, though there were a few places where it could have used a bit more. I did not see much on atypical development outside early childhood years which would be beneficial to include. It would also be nice to see a wider range of cultural studies. The text does not utilize a glossary, but the words are defined in the chapters and you can search the document if using as an e-book to find words which is even easier than a traditional glossary. Though if a student wants to print out the text, a glossary would be helpful.

This textbook is a straightforward discussion of human life span development which, as a field, is always growing. This book is largely current and accurate, but there should be updates as some references are older. Though the information is presented without bias and with references for further research.

The book is current and mostly up to date (as of 2019), though some of the references are a bit old. It worked when the authors were using the original work for a theory but other sources could be updated. For example, the media and development section didn’t touch social media. Including some of the newer studies would increase relevance to the technological age we are in.

The text is clear, easy to read, and understandable while still providing in-depth information. The graphics helped to clarify ideas, especially when explaining or comparing theories.

The look and feel of the text hold consistency through the document. Chapters were presented with continuing themes (such as Erikson’s stages in each life stage) and all work is referenced.

This text is sectioned into logical chunks that can be taught individually or in conjunction with each other. You do not need to read one chapter to understand the following one meaning the book could be taught any number of different ways to match with a variety of courses.

The book is organized into age periods, which is the way I think about the course information, though not the way I have always seen it presented in a text. So, the overall organization matched my thinking quite nicely. This organization also makes it easy to break the text into sections if the entire life span is separated over multiple classes (for example, if someone taught birth through adolescence only).

The text is pleasant to look at with calming colors and a variety of images and graphics that represent cultural diversity. There are no digital or navigational issues with the book.

I did not find any grammatical errors or issues.

The text is not offensive or insulting to any group and handles discussions of differences well. There are some representations of cultures and ages, though this book would benefit from a wider range of faces in images and of experimental studies conducted by / for nonwhite populations.

Reviewed by Francesca Kendris, Associate Professor, Bloomsburg University of Pennsylvania on 2/27/19

The book is quite comprehensive. It addresses all developmental milestones and the major theories that accompany them. It provides appropriate depth to each topic and offers a thorough explanation of the subject. The book does not possess an... read more

The book is accurate, error-free and unbiased. It is a straightforward presentation of Lifespan material in and objective and researched light. There are references at the end of each chapter to support the context of the text. There are no attempts to persuade the reader into to thinking that there is a correct or incorrect way to think about the material presented in each chapter. It is factual and the facts are supported by multiple references in most cases.

Relevance/Longevity rating: 3

The content is currently up-to-date (as of 2/2019). There are a variety of references provided for the material presented. Some of the references are current and some are rather dated. In some cases the authors went to the original source for a theory or study, which is fine for most clearly presenting the idea; however, at other times the references for material in the text were from the 1980's or 1990's and could soon be or already be considered obsolete. On the bright side, the material is written in such a way that it should not be difficult to up-date this text with more modern references throughout the book.

The book is very clear and written in easily understandable terms. Everything is defined and explained in a thorough manner for most undergraduate readers. Yet, it is sophisticated enough that I am planning on adopting it for my graduate human development course. This is because while it defines most terms and explains most theories, it does so in such a way that it provides enough depth to substantiate the theory or term presented.

This book is presented in order of development from pre-birth to old age and dying, touching upon milestones and developmental considerations along the way. It is internally sound and all work is referenced and themes are carried from chapter to chapter. For example, Erikson's Psychosocial Stages are presented in each chapter, as well as physical aspects of development. As noted earlier, all terminology is supported by referenced material which addes to the structural integrity of this text.

The book is readily divided up into different modules. One chapter is not dependent upon the next for a thorough understanding of each stage of development. The book could be assigned in any order without difficulty or too much self-referencing.

The book is organized in the most logical fashion for a developmental textbook: from birth to old age. It breaks down into the following chapters: An introduction; Heredity, Prenatal Development, Birth; Infancy & Toddlerhood; Early Childhood; Middle & Late Childhood; Adolescence; Emerging and Early Adulthood; Middle Adulthood; Late Adulthood; Death & Dying. It is free from technical jargon and presents material in a logical and understandable manner.

The images and diagrams in the text represent diverse populations in terms of age, gender, race and LGBTQA populations. The images and diagrams enhance the text and are pleasing to look at.

The book has excellent grammar and is free from typographical errors.

The text is not culturally offensive and the pictures are very diverse. The text itself makes good references and is inclusive of the LGBTQA populations. There are not too many other diverse populations represented, apart from age and gender. There are some considerations given to racial and ethnic differences but not enough. The book would benefit from more multicultural references.

Reviewed by Dan Bacon, Lecturer, San Diego State University on 2/22/19

The courses I teach primarily cover birth through middle childhood, so my review focused most heavily on chapters 1-5. The text is comprehensive in that it covers a wide range of topics you would expect in such a book. However, it may be improved by providing more depth in many of the areas. Even for use in a broad survey course, it would be nice to have more examples to help students understand the basic concepts they are reading about. For example, when covering longitudinal research, I might expect the author to mention an example of landmark longitudinal research in the field. There are certainly some examples (e.g., mentions Piaget when discussing case studies), but not to the degree I'm accustomed to in other textbooks. This text would also benefit from a glossary. While an eText allows students to search for terms easily, for those students who print the pdf (for preference or issues of accessibility), a glossary would be helpful.

A few errors stood out, and makes me imagine there are others in areas outside my expertise that I did not catch. One small example is the author lacks accuracy in stating: "Although the behaviorists were incorrect in their beliefs that it was not possible to measure thoughts and feelings". This is a misunderstanding and oversimplification of Skinner's analysis of public versus private events. Skinner, and other subsequent radical behaviorists, welcomed the scientific analysis of private events, and noted each individual is the observer of their own thoughts. The view that private events have no place in science was that of Watson and the methodological behaviorists. Being a half century past the shift to radical behaviorism, it may be time to start representing the field of behaviorism more accurately.

Mostly relevant with many 2016 citations. As a 2017 publication however, I would have expected the author to use more up-to-date data in some areas. For example, the author referenced a 2012 CDC publication with autism prevalence data from 2008 (1 in 88 children in US). It would have been more relevant to use 2016 publications which showed CDC prevalence rates were then 1 in 68 children in the US. With that said, the text is written in a way that could be easily updated (2018 publication of CDC numbers estimate the prevalence of ASD to be 1 in 59 in US).

I believe students would enjoy the clarity of this text, in terms of its concise writing. This text does a nice job of avoiding jargon, or clearly explaining the terminology when it is used. Where I think it could improve is in providing some additional examples to illustrate some concepts. Additional figures or links to videos might really benefit readers in their ability to quickly digest material.

There seems to be a clear framework that is easy to follow across all chapters. The text is easy to navigate in terms of its internal consistency.

This text could be used in a modular fashion. I could easily see taking chapters 1, 4 & 5 to use in my course on early and middle childhood. One area that adversely impacts modularity, which I touch on in the organization section as well, is how the book covers individuals with disabilities. For example, discussion of ASD is self contained in the chapter on early childhood. While the author briefly touches on the ability of adults with autism to live and work independently, this would be missed if using a modular approach of only assigning the chapter on adulthood.

As is typical of many other human development texts, the author does a nice job of consistently referencing hallmark theories (e.g. Erikson's stages of development) across the chronological chapters. This allows for the reader to build upon prior knowledge, but is done in a way that doesn't limit modularity too much. One area for improvement would be looking at atypical development and individuals experiencing disabilities across all chapters. Discussions of lifelong disabilities, such as Down syndrome, tended to be concentrated in early chapters, without touching on how individual's lives might be impacted in adulthood. This tends to be a problem with other human development texts as well, where atypical development is treated more as a token issue, often as a standalone chapter.

Images and charts are all clearly displayed in the pdf. While navigation could be improved by including links to more outside sources, or the ability to easily jump between chapters and topics by clicking on the index, there are no significant interface issues. I think users of eTexts have come to expect them to be a little easier to navigate through internal links between chapters or to a glossary (if it had one).

Grammatical errors did not strike me as an issue when reading this text.

While no text is perfect, as described by some other reviewers, I found myself wanting a greater focus on diversity. It would have been nice to see a focus not only on issues of race, ethnicity, and sexual orientation, but also on topics like military culture, immigrant culture, and disability culture.

Overall, I found this to be one of the strongest OER options for human development I've come across, at least for an undergraduate survey course. It is easy to think about topics that could be enhanced, such as cultural perspectives, but I think it is worth remembering that there is a finite amount of content that can be covered in one semester. No one text can meet the needs for all courses in developmental psychology or human development, but I thank the authors for creating and sharing something that likely fits the needs for some course very well.

Reviewed by Jennifer Parta-Arno, Psychology Instructor, Minnesota State on 2/7/19

Overall I found this text to be very comprehensive in covering all of the developmental stages and topics that I have used in other textbooks. It has a good layout of information that is for the most part relevant and up to date. read more

Content Accuracy rating: 3

I found at least one instance of out of date information- in Chapter 2 it discusses the law that went into effect in Tennessee that women who use drugs while pregnant can be charged, however that bill was allowed to sunset in 2016 and that is no longer the case so this is outdated information. Hopefully this OER text will be reviewed regularly and updated.

I noticed that in discussing Children and The Media in Chapter 4 there is but a brief paragraph or two and it only pertains to tv not social media or any devices such as smartphones or tablets which are a huge topic of developmental discussion. Also, I do not see any mention of social media and it's influence on teens in the chapter on adolescence. Would need to provide up to date and supplementary materials.

Yes I found the text and writing to be very precise, clear and easy to comprehend for students. Didn't seem to be too much terminology and if used it was defined pretty well.

Yes the layout and structure in which material/theories were covered was consistent throughout the text. The reader knows what to expect in terms of presentation and formatting.

There are quite a few sub-headings and divisions or modulations within the chapters. It isn't the easiest to "pull out a chunk of material" because of the pdf formatting. Would prefer linking to different sections.

I found the text to be fairly well organized.

I just have to say I am not a fan of the pdf format. I have used several other OER texts and they all have the ability to link to different sections within the text or chapters and you can present by Chapter instead of directing someone just to a certain page/chapter. As a hardcover book that is fine, however, I think that online users are expecting more functionality. Also, there aren't any links to supplemental videos, articles or activities which is another aspect that needs improvement.

Grammar was fine.

I appreciated the section on cultural differences in end of life decisions in the final chapter. Also, the section on gay and lesbian elders was refreshing to see included and something that is not currently in a text I use. I liked that!

Overall it is an ok option if you just essentially want an ebook, however as I stated above I think other OER resources have a lot more functionality than this text which is in a pdf format. Not very user friendly and wouldn't be my first choice to use for my students.

Reviewed by Lori Waters, Lecturer - Adjunct Faculty, Leeward Community College on 1/24/19

The research and experiment chapter was easily readable, attractive and enticing. Good, solid, well rounded text. I will highly recommend this text. read more

The research and experiment chapter was easily readable, attractive and enticing. Good, solid, well rounded text. I will highly recommend this text.

The content is accurate. A bit of bias is felt. However, due to readers biases the authors did a good job of masking biases with good solid research that was sited and created unbiased accurate content.

Graphics and photos are helpful and are nicely relevant and certainly adds great clarity. The text easily blends the valid content and includes relevant updates that flow nicely. Organized to easily create new updates. Epigenetics could have been more thoroughly covered.

The text is written with excellent clarity with a simplification of jargon that makes material easy to grasp quickly.

The text is consistent, with topics flowing together and broken up into easily readable subheadings, and tables/graphs/charts/images all flowing nicely. Terminology is consistent.

Good modularity which is consistent throughout the text. Subheadings are clear, easy to read and flow nicely to the eye. Self-referential is not present. Text is easily divisible into smaller reading sections that make it easy to grab topics out of their context. Modularity is also well balanced with the flow, fluidity and relatedness of previous subunits. Especially good flow for online reading and easy page accessibility.

It is easy to page up and down and clearly see the logical organization, again especially as an online pdf. The organization is excellent!

The charts, images, photos and graphics are free of distractions regarding interface issues. They are nicely placed and spaced throughout the text and fall appealingly on the page. Easy for the eye to track and to organize.

The textbook is grammatically correct.

Love the picture on the cover! Great start. Excellent examples that are culturally relevant, especially in the “classroom” section of chapter 5 and remain consistently exceptional throughout the text.

I will use this textbook the next opportunity I have to teach Human Development with the option of choosing which text to use!!!!

Reviewed by Glinda Rawls, Associate Professor, Western Michigan University on 12/14/18

Much of the content presented in the chapters is standard for most lifespan development textbooks. read more

Much of the content presented in the chapters is standard for most lifespan development textbooks.

I did not notice many errors, however there were places in the the textbook where the authors clearly presented their bias. For example, in chapter 4 when discussing childhood disciplinary practices the authors only discussed the harmful affects of corporal punishment; however, there are other scholars who have highlighted the benefit of such disciplinary practices especially among different cultural groups. Both perspectives should have been presented.

In some areas, the content was not up to date. For example, in chapter 10 which contains information about death and dying the authors only mentioned that in 1997 Oregon had laws which facilitate dignity in dying where patients can choose to die on their own terms. However, since 1997 I believe there are three states (California, Colorado, and Hawaii) and Washington DC who all have passed these laws. This needs to be updated in the textbook. Also in chapter 8 the authors really did not discuss how women are delaying marriage and child-bearing along with the content related to marriage. And the information on marriage could have included more topics related to cultural diversity because African American women tend to have the highest rates of being single than other ethnic groups. This was left out of the textbook. Another omission was in discussing maternal mortality. The authors only cited PID as the cause for infertility but PCOS and endometriosis are two other conditions which could contribute to infertility in women. So the authors should update this too.

The textbook was written in clear and uncomplicated way. The information presented in this textbook is succinct and brief which may make undergraduate students more apt to read this textbook. It was very simple and easy to read.

I really liked how the authors used Erickson's lifespan development across several chapters. I have used other lifespan development textbooks that followed this same format. This consistency allowed the reader to have easy access to the theory so that they could apply it to various stages of development.

Each chapter had several subheadings and headings. The material was arranged in such a way that the content flowed very well. The subheadings made sense and were relevant to the larger headings.

The chapters followed the normal stages of development and were well organized.

I am not sure if this would be possible but it would be helpful if the reader could click onto the chapter and just pull it up. Since the document is in a pdf format, the reader has to scroll up and down if they wanted to move back and forth in the textbook. This was a bit cumbersome.

I did not notice any grammatical errors.

The authors made an effort to include cultural diversity and LGBT issues in the textbook. I certainly applaud their efforts, but in some ways things fell a little short in this area. For example, issues of adverse childhood experiences was not mentioned. Social issues like poverty, childhood homelessness and incarcerated parents were also omitted. It seems as though the book could also benefit from including some sociological perspectives to deepen their attempts to include diversity. They also did not include all types of families in chapter 5. They did not include trans-racial adoption or multicultural families where the parents are of different races. So the area of cultural diversity could be enhanced.

Overall this textbook would be useful in a undergraduate course. The instructor would definitely have to supplement the materials to include content that is not only up to date but also includes more sociological perspectives in understanding lifespan development.

Reviewed by Jamie Nordling, Assistant Professor, Augustana College on 11/18/18

The book content matches what I currently teach. read more

The book content matches what I currently teach.

I did not find any big errors. They do discuss how the Attachment Q-Sort is a solid, contemporary way to measure attachment, but there are issues with this method.

I did not notice any issues with relevance.

The prose is clear and easy to understand.

Consistency rating: 3

There are some topics that are not discussed enough (e.g., temperament), and some topics that are not even developmental in scope that are covered in too much detail (e.g., components of memory).

There are subheadings.

Organization/Structure/Flow rating: 3

There are several chapters that seem choppy (i.e., the sections stand alone and are not well connected).

I had no issues.

Nothing stood out.

Culture is covered, but I believe it could be covered even more.

Overall, I believe this textbook provides a good overview on human development. The writing is well-suited for introductory students.

Some of the concepts that were included that stand out in a positive way include: (a) a good description of how the field has changed from just looking at childhood to looking at the whole lifespan; (b) the use of the multidimensional, multidirectional, multidisciplinary, multicontextual, and plastic approach to development; (c) the inclusion of a description about archival data/secondary analysis, because a lot of developmental data is longitudinal; and (d) the theories of aging (i.e., why do we age).

Some of the more minor issues include: (a) There were some structure issues. I think some of this could be solved by including more clear headings or including an outline of the topics that would be covered in each chapter. It does feel a little like, “Here’s everything you need to know about this age,” without good transitions or an understanding of how topics are related to one another. Students may struggle with processing all of the information as it is presented. (b) There were some citation issues. I want students to have good models for their own writing. There were several sections of the book that made claims about research findings without a single citation. As examples, SES was linked to poor health and various other outcomes (p. 11) without a single citation. Also, the section on genetics (Ch. 2) does not have enough citations to support the claims stated. This citation issue was not found in every chapter – some sections were better than others—but it happened enough to where I took notice. (c) I would ideally like more discussions of culture; however, the book does talk about some aspect of culture in every chapter. (d) There were some topics that were discussed in too much detail given that the topics are not inherently developmental. For example, the authors go into a lot of detail about the different types of memory in chapter 4 (e.g., discusses rehearsal, different types of declarative memories) and into a lot of detail about sex in chapter 7 (e.g., phases in sexual response cycle, role of the hypothalamus, STIs). (e) And there are some topics that, while they may be developmental, are described in more detail than I have seen before in a developmental textbook. For example, (a) there was more detail than other books on prenatal development, pregnancy, and childbirth;(b) I have never seen as much detail about Piaget’s theory in any textbook (not even a child development book that has more time to focus on Piaget); (c) there was a lot of detail on sports and sports involvement, and (d) the sections on childhood issues (e.g., genetic disorders, childhood disabilities, communication disorders) were too detailed given that they seemed more biological or medical than psychological. Note that I am not saying that these issues do not have psychological components, but rather that that is not the way they are presented. They’re presented simply as biological/medical descriptions. (f) There were also some topics that were not detailed enough. My biggest area of complaint in this area relates to temperament. The authors spent too much time focusing on Thomas and Chess, which we know is an outdated view, and spent very little time talking about contemporary approaches to temperament or children’s personality.

Some of the more major issues include: (a) One of the things that bothers me about this textbook is that there are VERY few critical thinking questions that lead students to think deeply about the material. Of course, these questions can be addressed in the classroom, but the book does not include any real aspects of active learning. (b) I wish the textbook had more “science” built into it. The introduction sets up the field as scientific, but there is often little discussion about how the scientific method is essential to the findings presented. Chapter 3 stands out as doing this better – there is more incorporation of research methods, study findings, and some issues with measurement – but other chapters were deficient (c) Relatedly, given that I am teaching my lifespan course in a psychology department, we talk about how developmental psychology is much more than understanding the “whats” and the “whens” of development. We really are aiming to uncover the “hows,” “for whoms,” and “under what conditions”. Essentially, I want my students to better understand mechanisms. This book, compared to about five others that I have either used or previously reviewed, seems to talk more about the “whats” and “whens”, and in my opinion, these are less psychological. For example, topics like (a) when to introduce solid foods, (b) toilet training tips, (c) healthy eating, and (d) how to choose between preschool programs seem more suited to students who are taking a child development course in high school rather than students who are pursuing the scientific study of human development. I realize that this may have been the goal of the authors – perhaps they wanted their textbook to have flexibility for different types of courses. For me, this takes away from the messages that I tell my students.

Will I use this book in my course? In short, I have not decided yet. As noted above, the content that I normally expect my students to know (except for temperament!) is present within this textbook. However, students are not going to be asked to use their critical thinking or scientific literacy skills in this book as much as other books.

Reviewed by Lisa Dunkley, Assistant Professor, East Tennessee State University on 10/23/18

The text is comparative to other texts in the field. However, disability inclusive issues across the lifespan would add for a more comprehensive outlook. read more

The text is comparative to other texts in the field. However, disability inclusive issues across the lifespan would add for a more comprehensive outlook.

Book has used prominent literature to support context.

Information included is relevant to each topic area and today's society.

Book is easy to follow and undergraduate level students will be able to comprehend the information included in the text.

Consistent with related texts.

Book is organized into sections that make it easy to break up reading the content.

The book has a good flow and is easy to understand. Flow is consistent with others in the field.

Images included are appropriate however more vibrant images would make for a more user-friendly book.

None observed.

Book is not culturally insensitive. However more references to other cultures would make for a more inclusive book.

The book is easy to follow and navigate. Information is consistent with for sale texts in the field.

Reviewed by Christopher Belser, Assistant Professor, University of New Orleans on 6/19/18

Overall, the text covers a wide array of topics within this subject, but the degree of depth to which these topics are covered varies. Career development isn’t introduced until the section on emerging adulthood. Research dating back 50+ years... read more

Overall, the text covers a wide array of topics within this subject, but the degree of depth to which these topics are covered varies.

Career development isn’t introduced until the section on emerging adulthood. Research dating back 50+ years discusses career development in the context of childhood and adolescence. Not including career development is a disservice to the career development programming that has been done and continues to be done in K-12 settings.

The textbook covers many of the theories of human development, but does not introduce all of them in the first chapter. Only a select few are covered in this introduction; other theories are introduced in later chapters in the point in the lifespan during which this theory becomes most salient. This is problematic, as the stages are not firmly restricted to these age bands. A review of all theories in the beginning would be helpful to the reader. The book does not cover some theories (e.g., Spiritual development).

Adverse childhood experiences (ACEs) are not covered at all, and the research has been around for 20 years. Any discussion of human development that does not include this research is incomplete.

Other topics (e.g., sexuality, gender identity) are presented in greater detail than other texts I’ve seen. The discussion of grief models, especially refutations of the Kubler-Ross model, are excellent and represent modern research.

The information presented in the text appears to be accurate, with the exception of a few areas that need to be updated with contemporary research.

The text does not include contemporary research on Adverse Childhood Experiences, neuroimaging, and neuropsychology. This contemporary research has enhanced or refuted many long-held theories and must be represented in any discussion of human development

The information presented is written clearly and in a way that is easy to understand and comprehend.

The book appears to be presented in a consistent manner, with regard to terminology, framework, and layout. The authors were not consistent with the depth to which topics are covered; this may be an indication of the authors areas of interest and areas for development.

The book is chunked very well. The chapters are broken down in a rational manner and each chapter includes many smaller sections with headings.

The book is chunked very well. The chapters are broken down in a rational manner and each chapter includes many smaller sections with headings. The authors were not consistent with the depth to which topics are covered; this may be an indication of the authors areas of interest and areas for development.

The book has a very good look. The table of contents is navigable, and there are links to sources embedded within. The graphics, tables, and charts are clear and readable.

The authors use correct grammar and have edited the book well for mechanical and grammatical errors.

The book presents cultural information more completely in some areas and more incompletely in other areas. This is an area of the text that could use additional fine-tuning. Stereotype threat introduced in the section on age, although the research emerged from discussions of race and ethnicity. The book covers sexuality and gender identity in more depth than other texts I’ve used.

Based on the current edition of the text, I cannot say that I would use this book over a traditionally published text without having to provide many additional readings to supplement incomplete areas. At best, there are chapters from this text I could see assigning to supplement additional readings.

Chapter 1: Introduction to Lifespan Development
Chapter 2: Heredity, Prenatal Development, and Birth
Chapter 3: Infancy and Toddlerhood
Chapter 4: Early Childhood
Chapter 5: Middle and Late Childhood
Chapter 6: Adolescence
Chapter 7: Emerging and Established Adulthood
Chapter 8: Middle Adulthood
Chapter 9: Late Adulthood
Chapter 10: Death and Dying

Ancillary Material

About the book.

Developmental Psychology, also known as Human Development or Lifespan Development, is the scientific study of ways in which people change, as well as stay the same, from conception to death. You will no doubt discover in the course of studying that the field examines change across a broad range of topics. These include physical and other psychophysiological processes, cognition, language, and psychosocial development, including the impact of family and peers.

About the Contributors

Martha Lally is an Instructor in the Psychology department at the College of Lake County.

Suzanne Valentine-French is an Instructor in the Psychology department at the College of Lake County.

Contribute to this Page

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Ch 3: Lifespan Development

A picture shows two intertwined hands. One is the large hand of an adult, and the other is the tiny hand of an infant. The infant’s entire hand grasp is about the size of a single adult finger.

Welcome to the story of your life. In this chapter, we will explore the fascinating tale of how you have grown and developed into the person you are today. We will also look at some ideas about who you will grow into tomorrow. Yours is a story of lifespan development (Figure 1), from the start of life to the end.

The process of human growth and development is more obvious in infancy and childhood, yet your development is happening this moment and will continue, minute by minute, for the rest of your life. Who you are today and who you will be in the future depends on a blend of genetics, environment, culture, relationships, and more, as you continue through each phase of life. You have experienced firsthand much of what is discussed in this chapter. Now consider what psychological science has to say about your physical, cognitive, and psychosocial development, from the womb to the tomb.

Theories of Development

There are many theories regarding how babies and children grow and develop into happy, healthy adults. Sigmund Freud suggested that we pass through a series of psychosexual stages in which our energy is focused on certain erogenous zones on the body. Eric Erikson modified Freud’s ideas and suggested a theory of psychosocial development. Erikson said that our social interactions and successful completion of social tasks shape our sense of self. Jean Piaget proposed a theory of cognitive development that explains how children think and reason as they move through various stages. Finally, Lawrence Kohlberg turned his attention to moral development. He said that we pass through three levels of moral thinking that build on our cognitive development. You’ll learn about each of these theories in this section.

Learning Objectives

Describe the three major issues in development: continuity and discontinuity, one common course of development or many unique courses of development, and nature versus nurture

What Is Lifespan Development?

My heart leaps up when I behold A rainbow in the sky: So was it when my life began; So is it now I am a man; So be it when I shall grow old, Or let me die! The Child is father of the Man; And I could wish my days to be Bound each to each by natural piety. (Wordsworth, 1802)

Connect the Concepts: Research Methods in Developmental Psychology

In one classic example of this research method being applied to a study of lifespan development Sigmund Freud analyzed the development of a child known as “Little Hans” (Freud, 1909/1949). Freud’s findings helped inform his theories of psychosexual development in children, which you will learn about later in this module. Little Genie, the subject of a case study discussed in the module on thinking and intelligence, provides another example of how psychologists examine developmental milestones through detailed research on a single individual. In Genie’s case, her neglectful and abusive upbringing led to her being unable to speak until, at age 13, she was removed from that harmful environment. As she learned to use language, psychologists were able to compare how her language acquisition abilities differed when occurring in her late-stage development compared to the typical acquisition of those skills during the ages of infancy through early childhood (Fromkin, Krashen, Curtiss, Rigler, & Rigler, 1974; Curtiss, 1981).

Across these three domains—physical, cognitive, and psychosocial—the normative approach to development is also discussed. This approach asks, “What is normal development?” In the early decades of the 20th century, normative psychologists studied large numbers of children at various ages to determine norms (i.e., average ages) of when most children reach specific developmental milestones in each of the three domains (Gesell, 1933, 1939, 1940; Gesell & Ilg, 1946; Hall, 1904). Although children develop at slightly different rates, we can use these age-related averages as general guidelines to compare children with same-age peers to determine the approximate ages they should reach specific normative events called developmental milestones (e.g., crawling, walking, writing, dressing, naming colors, speaking in sentences, and starting puberty).

Not all normative events are universal, meaning they are not experienced by all individuals across all cultures. Biological milestones, such as puberty, tend to be universal, but social milestones, such as the age when children begin formal schooling, are not necessarily universal; instead, they affect most individuals in a particular culture (Gesell & Ilg, 1946). For example, in developed countries children begin school around 5 or 6 years old, but in developing countries, like Nigeria, children often enter school at an advanced age, if at all (Huebler, 2005; United Nations Educational, Scientific, and Cultural Organization [UNESCO], 2013).

Link to Learning

Issues in developmental psychology, is development continuous or discontinuous.

Continuous development views development as a cumulative process, gradually improving on existing skills (Figure 2). With this type of development, there is gradual change. Consider, for example, a child’s physical growth: adding inches to her height year by year. In contrast, theorists who view development as discontinuous believe that development takes place in unique stages: It occurs at specific times or ages. With this type of development, the change is more sudden, such as an infant’s ability to conceive object permanence.

Continuous and Discontinuous development are shown side by side using two separate pictures. The first picture is a triangle labeled “Continuous Development” which slopes upward from Infancy to Adulthood in a straight line. The second picture is 4 bars side by side labeled “Discontinuous Development” which get higher from Infancy to Adulthood. These bars resemble a staircase.

Is There One Course of Development or Many?

For instance, let’s look at the Aché society in Paraguay. They spend a significant amount of time foraging in forests. While foraging, Aché mothers carry their young children, rarely putting them down in order to protect them from getting hurt in the forest. Consequently, their children walk much later: They walk around 23–25 months old, in comparison to infants in Western cultures who begin to walk around 12 months old. However, as Aché children become older, they are allowed more freedom to move about, and by about age 9, their motor skills surpass those of U.S. children of the same age: Aché children are able to climb trees up to 25 feet tall and use machetes to chop their way through the forest (Kaplan & Dove, 1987). As you can see, our development is influenced by multiple contexts, so the timing of basic motor functions may vary across cultures. However, the functions themselves are present in all societies (Figure 3).

Photograph A shows two children wearing inner tubes playing in the shallow water at the beach. Photograph B shows two children playing in the sand at a beach.

How Do Nature and Nurture Influence Development?

Are we who we are because of nature (biology and genetics), or are we who we are because of nurture (our environment and culture)? This longstanding question is known in psychology as the nature versus nurture debate. It seeks to understand how our personalities and traits are the product of our genetic makeup and biological factors, and how they are shaped by our environment, including our parents, peers, and culture. For instance, why do biological children sometimes act like their parents—is it because of genetics or because of early childhood environment and what the child has learned from the parents? What about children who are adopted—are they more like their biological families or more like their adoptive families? And how can siblings from the same family be so different?

We are all born with specific genetic traits inherited from our parents, such as eye color, height, and certain personality traits. Beyond our basic genotype, however, there is a deep interaction between our genes and our environment: Our unique experiences in our environment influence whether and how particular traits are expressed, and at the same time, our genes influence how we interact with our environment (Diamond, 2009; Lobo, 2008). This module will show that there is a reciprocal interaction between nature and nurture as they both shape who we become, but the debate continues as to the relative contributions of each.

Dig Deeper: The Achievement Gap: How Does Socioeconomic Status Affect Development?

The achievement gap refers to the persistent difference in grades, test scores, and graduation rates that exist among students of different ethnicities, races, and—in certain subjects—sexes (Winerman, 2011). Research suggests that these achievement gaps are strongly influenced by differences in socioeconomic factors that exist among the families of these children. While the researchers acknowledge that programs aimed at reducing such socioeconomic discrepancies would likely aid in equalizing the aptitude and performance of children from different backgrounds, they recognize that such large-scale interventions would be difficult to achieve. Therefore, it is recommended that programs aimed at fostering aptitude and achievement among disadvantaged children may be the best option for dealing with issues related to academic achievement gaps (Duncan & Magnuson, 2005).

Low-income children perform significantly more poorly than their middle- and high-income peers on a number of educational variables: They have significantly lower standardized test scores, graduation rates, and college entrance rates, and they have much higher school dropout rates. There have been attempts to correct the achievement gap through state and federal legislation, but what if the problems start before the children even enter school?

Psychologists Betty Hart and Todd Risley (2006) spent their careers looking at early language ability and progression of children in various income levels. In one longitudinal study, they found that although all the parents in the study engaged and interacted with their children, middle- and high-income parents interacted with their children differently than low-income parents. After analyzing 1,300 hours of parent-child interactions, the researchers found that middle- and high-income parents talk to their children significantly more, starting when the children are infants. By 3 years old, high-income children knew almost double the number of words known by their low-income counterparts, and they had heard an estimated total of 30 million more words than the low-income counterparts (Hart & Risley, 2003). And the gaps only become more pronounced. Before entering kindergarten, high-income children score 60% higher on achievement tests than their low-income peers (Lee & Burkam, 2002).

There are solutions to this problem. At the University of Chicago, experts are working with low-income families, visiting them at their homes, and encouraging them to speak more to their children on a daily and hourly basis. Other experts are designing preschools in which students from diverse economic backgrounds are placed in the same classroom. In this research, low-income children made significant gains in their language development, likely as a result of attending the specialized preschool (Schechter & Byeb, 2007). What other methods or interventions could be used to decrease the achievement gap? What types of activities could be implemented to help the children of your community or a neighboring community?

Think It Over

How are you different today from the person you were at 6 years old? What about at 16 years old? How are you the same as the person you were at those ages?
Your 3-year-old daughter is not yet potty trained. Based on what you know about the normative approach, should you be concerned? Why or why not?

Lifespan Theories

Define Freud’s theory of psychosexual development
Describe the major tasks of child and adult psychosocial development according to Erikson
Discuss Piaget’s view of cognitive development and apply the stages to understanding childhood cognition
Describe Kohlberg’s theory of moral development
Compare and contrast the strengths and weaknesses of major developmental theories

Psychosexual Theory of Development

Sigmund Freud (1856–1939) believed that personality develops during early childhood. For Freud, childhood experiences shape our personalities and behavior as adults. Freud viewed development as discontinuous; he believed that each of us must pass through a serious of stages during childhood, and that if we lack proper nurturance and parenting during a stage, we may become stuck, or fixated, in that stage. Freud’s stages are called the stages of psychosexual development . According to Freud, children’s pleasure-seeking urges are focused on a different area of the body, called an erogenous zone, at each of the five stages of development: oral, anal, phallic, latency, and genital.

While most of Freud’s ideas have not found support in modern research, we cannot discount the contributions that Freud has made to the field of psychology. Psychologists today dispute Freud’s psychosexual stages as a legitimate explanation for how one’s personality develops, but what we can take away from Freud’s theory is that personality is shaped, in some part, by experiences we have in childhood. These stages are discussed in detail in the personality chapter in OpenStax .

Psychosocial Theory of Development

Erik Erikson (1902–1994) (Figure 4), another stage theorist, took Freud’s theory and modified it as psychosocial theory. Erikson’s psychosocial development emphasizes the social nature of our development rather than its sexual nature. While Freud believed that personality is shaped only in childhood, Erikson proposed that personality development takes place all through the lifespan. Erikson suggested that how we interact with others is what affects our sense of self, or what he called the ego identity.

A photograph depicts Erik Erikson in his later years.

Erikson proposed that we are motivated by a need to achieve competence in certain areas of our lives. According to psychosocial theory, we experience eight stages of development over our lifespan, from infancy through late adulthood. At each stage there is a conflict, or task, that we need to resolve. Successful completion of each developmental task results in a sense of competence and a healthy personality. Failure to master these tasks leads to feelings of inadequacy.

According to Erikson (1963), trust is the basis of our development during infancy (birth to 12 months). Therefore, the primary task of this stage is trust versus mistrust. Infants are dependent upon their caregivers, so caregivers who are responsive and sensitive to their infant’s needs help their baby to develop a sense of trust; their baby will see the world as a safe, predictable place. Unresponsive caregivers who do not meet their baby’s needs can engender feelings of anxiety, fear, and mistrust; their baby may see the world as unpredictable.

As toddlers (ages 1–3 years) begin to explore their world, they learn that they can control their actions and act on the environment to get results. They begin to show clear preferences for certain elements of the environment, such as food, toys, and clothing. A toddler’s main task is to resolve the issue of autonomy versus shame and doubt, by working to establish independence. This is the “me do it” stage. For example, we might observe a budding sense of autonomy in a 2-year-old child who wants to choose her clothes and dress herself. Although her outfits might not be appropriate for the situation, her input in such basic decisions has an effect on her sense of independence. If denied the opportunity to act on her environment, she may begin to doubt her abilities, which could lead to low self-esteem and feelings of shame.

Once children reach the preschool stage (ages 3–6 years), they are capable of initiating activities and asserting control over their world through social interactions and play. According to Erikson, preschool children must resolve the task of initiative versus guilt. By learning to plan and achieve goals while interacting with others, preschool children can master this task. Those who do will develop self-confidence and feel a sense of purpose. Those who are unsuccessful at this stage—with their initiative misfiring or stifled—may develop feelings of guilt. How might over-controlling parents stifle a child’s initiative?

During the elementary school stage (ages 6–12), children face the task of industry versus inferiority. Children begin to compare themselves to their peers to see how they measure up. They either develop a sense of pride and accomplishment in their schoolwork, sports, social activities, and family life, or they feel inferior and inadequate when they don’t measure up. What are some things parents and teachers can do to help children develop a sense of competence and a belief in themselves and their abilities?

In adolescence (ages 12–18), children face the task of identity versus role confusion. According to Erikson, an adolescent’s main task is developing a sense of self. Adolescents struggle with questions such as “Who am I?” and “What do I want to do with my life?” Along the way, most adolescents try on many different selves to see which ones fit. Adolescents who are successful at this stage have a strong sense of identity and are able to remain true to their beliefs and values in the face of problems and other people’s perspectives. What happens to apathetic adolescents, who do not make a conscious search for identity, or those who are pressured to conform to their parents’ ideas for the future? These teens will have a weak sense of self and experience role confusion. They are unsure of their identity and confused about the future.

People in early adulthood (i.e., 20s through early 40s) are concerned with intimacy versus isolation. After we have developed a sense of self in adolescence, we are ready to share our life with others. Erikson said that we must have a strong sense of self before developing intimate relationships with others. Adults who do not develop a positive self-concept in adolescence may experience feelings of loneliness and emotional isolation.

When people reach their 40s, they enter the time known as middle adulthood, which extends to the mid-60s. The social task of middle adulthood is generativity versus stagnation. Generativity involves finding your life’s work and contributing to the development of others, through activities such as volunteering, mentoring, and raising children. Those who do not master this task may experience stagnation, having little connection with others and little interest in productivity and self-improvement.

From the mid-60s to the end of life, we are in the period of development known as late adulthood. Erikson’s task at this stage is called integrity versus despair. He said that people in late adulthood reflect on their lives and feel either a sense of satisfaction or a sense of failure. People who feel proud of their accomplishments feel a sense of integrity, and they can look back on their lives with few regrets. However, people who are not successful at this stage may feel as if their life has been wasted. They focus on what “would have,” “should have,” and “could have” been. They face the end of their lives with feelings of bitterness, depression, and despair. Table 1 summarizes the stages of Erikson’s theory.

Cognitive Theory of Development

Jean Piaget (1896–1980) is another stage theorist who studied childhood development (Figure 5). Instead of approaching development from a psychoanalytical or psychosocial perspective, Piaget focused on children’s cognitive growth. He believed that thinking is a central aspect of development and that children are naturally inquisitive. However, he said that children do not think and reason like adults (Piaget, 1930, 1932). His theory of cognitive development holds that our cognitive abilities develop through specific stages, which exemplifies the discontinuity approach to development. As we progress to a new stage, there is a distinct shift in how we think and reason.

A photograph depicts Jean Piaget in his later years.

Piaget said that children develop schemata, sometimes called schemas, to help them understand the world. Schemata are concepts (mental models) that are used to help us categorize and interpret information. By the time children have reached adulthood, they have created schemata for almost everything. When children learn new information, they adjust their schemata through two processes: assimilation and accommodation. First, they assimilate new information or experiences in terms of their current schemata: assimilation is when they take in information that is comparable to what they already know. Accommodation describes when they change their schemata based on new information. This process continues as children interact with their environment.

For example, 2-year-old Blake learned the schema for dogs because his family has a Labrador retriever. When Blake sees other dogs in his picture books, he says, “Look mommy, dog!” Thus, he has assimilated them into his schema for dogs. One day, Blake sees a sheep for the first time and says, “Look mommy, dog!” Having a basic schema that a dog is an animal with four legs and fur, Blake thinks all furry, four-legged creatures are dogs. When Blake’s mom tells him that the animal he sees is a sheep, not a dog, Blake must accommodate his schema for dogs to include more information based on his new experiences. Blake’s schema for dog was too broad, since not all furry, four-legged creatures are dogs. He now modifies his schema for dogs and forms a new one for sheep.

Like Freud and Erikson, Piaget thought development unfolds in a series of stages approximately associated with age ranges. He proposed a theory of cognitive development that unfolds in four stages: sensorimotor, preoperational, concrete operational, and formal operational.

The first stage is the sensorimotor stage, which lasts from birth to about 2 years old. During this stage, children learn about the world through their senses and motor behavior. Young children put objects in their mouths to see if the items are edible, and once they can grasp objects, they may shake or bang them to see if they make sounds. Between 5 and 8 months old, the child develops object permanence , which is the understanding that even if something is out of sight, it still exists (Bogartz, Shinskey, & Schilling, 2000). According to Piaget, young infants do not remember an object after it has been removed from sight. Piaget studied infants’ reactions when a toy was first shown to an infant and then hidden under a blanket. Infants who had already developed object permanence would reach for the hidden toy, indicating that they knew it still existed, whereas infants who had not developed object permanence would appear confused.

Please take a few minutes to view this brief video demonstrating different children’s ability to understand object permanence:

You can view the transcript for “Piaget – Stage 1 – Sensorimotor Stage : Object Permanence” here (opens in new window) .

In Piaget’s view, around the same time children develop object permanence, they also begin to exhibit stranger anxiety, which is a fear of unfamiliar people. Babies may demonstrate this by crying and turning away from a stranger, by clinging to a caregiver, or by attempting to reach their arms toward familiar faces such as parents. Stranger anxiety results when a child is unable to assimilate the stranger into an existing schema; therefore, she can’t predict what her experience with that stranger will be like, which results in a fear response.

Piaget’s second stage is the preoperational stage , which is from approximately 2 to 7 years old. In this stage, children can use symbols to represent words, images, and ideas, which is why children in this stage engage in pretend play. A child’s arms might become airplane wings as he zooms around the room, or a child with a stick might become a brave knight with a sword. Children also begin to use language in the preoperational stage, but they cannot understand adult logic or mentally manipulate information (the term operational refers to logical manipulation of information, so children at this stage are considered to be pre -operational). Children’s logic is based on their own personal knowledge of the world so far, rather than on conventional knowledge. For example, dad gave a slice of pizza to 10-year-old Keiko and another slice to her 3-year-old brother, Kenny. Kenny’s pizza slice was cut into five pieces, so Kenny told his sister that he got more pizza than she did. Children in this stage cannot perform mental operations because they have not developed an understanding of conservation , which is the idea that even if you change the appearance of something, it is still equal in size as long as nothing has been removed or added.

This video shows a 4.5-year-old boy in the preoperational stage as he responds to Piaget’s conservation tasks.

You can view the transcript for “A typical child on Piaget’s conservation tasks” here (opens in new window) .

During this stage, we also expect children to display egocentrism , which means that the child is not able to take the perspective of others. A child at this stage thinks that everyone sees, thinks, and feels just as they do. Let’s look at Kenny and Keiko again. Keiko’s birthday is coming up, so their mom takes Kenny to the toy store to choose a present for his sister. He selects an Iron Man action figure for her, thinking that if he likes the toy, his sister will too. An egocentric child is not able to infer the perspective of other people and instead attributes his own perspective. At some point during this stage and typically between 3 and 5 years old, children come to understand that people have thoughts, feelings, and beliefs that are different from their own. This is known as theory-of-mind (TOM).

Piaget developed the Three-Mountain Task to determine the level of egocentrism displayed by children. Children view a 3-dimensional mountain scene from one viewpoint, and are asked what another person at a different viewpoint would see in the same scene. Watch the Three-Mountain Task in action in this short video from the University of Minnesota and the Science Museum of Minnesota.

You can view the transcript for “Piaget’s Mountains Task” here (opens in new window) .

Piaget’s third stage is the concrete operational stage , which occurs from about 7 to 11 years old. In this stage, children can think logically about real (concrete) events; they have a firm grasp on the use of numbers and start to employ memory strategies. They can perform mathematical operations and understand transformations, such as addition is the opposite of subtraction, and multiplication is the opposite of division. In this stage, children also master the concept of conservation: Even if something changes shape, its mass, volume, and number stay the same. For example, if you pour water from a tall, thin glass to a short, fat glass, you still have the same amount of water. Remember Keiko and Kenny and the pizza? How did Keiko know that Kenny was wrong when he said that he had more pizza?

Children in the concrete operational stage also understand the principle of reversibility , which means that objects can be changed and then returned back to their original form or condition. Take, for example, water that you poured into the short, fat glass: You can pour water from the fat glass back to the thin glass and still have the same amount (minus a couple of drops).

The fourth, and last, stage in Piaget’s theory is the formal operational stage , which is from about age 11 to adulthood. Whereas children in the concrete operational stage are able to think logically only about concrete events, children in the formal operational stage can also deal with abstract ideas and hypothetical situations. Children in this stage can use abstract thinking to problem solve, look at alternative solutions, and test these solutions. In adolescence, a renewed egocentrism occurs. For example, a 15-year-old with a very small pimple on her face might think it is huge and incredibly visible, under the mistaken impression that others must share her perceptions.

Beyond Formal Operational Thought

As with other major contributors of theories of development, several of Piaget’s ideas have come under criticism based on the results of further research. For example, several contemporary studies support a model of development that is more continuous than Piaget’s discrete stages (Courage & Howe, 2002; Siegler, 2005, 2006). Many others suggest that children reach cognitive milestones earlier than Piaget describes (Baillargeon, 2004; de Hevia & Spelke, 2010).

According to Piaget, the highest level of cognitive development is formal operational thought, which develops between 11 and 20 years old. However, many developmental psychologists disagree with Piaget, suggesting a fifth stage of cognitive development, known as the postformal stage (Basseches, 1984; Commons & Bresette, 2006; Sinnott, 1998). In postformal thinking, decisions are made based on situations and circumstances, and logic is integrated with emotion as adults develop principles that depend on contexts. One way that we can see the difference between an adult in postformal thought and an adolescent in formal operations is in terms of how they handle emotionally charged issues.

It seems that once we reach adulthood our problem solving abilities change: As we attempt to solve problems, we tend to think more deeply about many areas of our lives, such as relationships, work, and politics (Labouvie-Vief & Diehl, 1999). Because of this, postformal thinkers are able to draw on past experiences to help them solve new problems. Problem-solving strategies using postformal thought vary, depending on the situation. What does this mean? Adults can recognize, for example, that what seems to be an ideal solution to a problem at work involving a disagreement with a colleague may not be the best solution to a disagreement with a significant other.

Explain how you would use your understanding of one of the major developmental theories (psychosexual, psychosocial, or cognitive) to deal with each of the difficulties listed below:

Your infant daughter puts everything in her mouth, including the dog’s food.
Your eight-year-old son is failing math; all he cares about is baseball.
Your two-year-old daughter refuses to wear the clothes you pick for her every morning, which makes getting dressed a twenty-minute battle.
Your sixty-eight-year-old neighbor is chronically depressed and feels she has wasted her life.
Your 18-year-old daughter has decided not to go to college. Instead she’s moving to Colorado to become a ski instructor.
Your 11-year-old son is the class bully.

Theory of Moral Development

A major task beginning in childhood and continuing into adolescence is discerning right from wrong. Psychologist Lawrence Kohlberg (1927–1987) extended upon the foundation that Piaget built regarding cognitive development. Kohlberg believed that moral development, like cognitive development, follows a series of stages. To develop this theory, Kohlberg posed moral dilemmas to people of all ages, and then he analyzed their answers to find evidence of their particular stage of moral development. Before reading about the stages, take a minute to consider how you would answer one of Kohlberg’s best-known moral dilemmas, commonly known as the Heinz dilemma:

In Europe, a woman was near death from a special kind of cancer. There was one drug that the doctors thought might save her. It was a form of radium that a druggist in the same town had recently discovered. The drug was expensive to make, but the druggist was charging ten times what the drug cost him to make. He paid $200 for the radium and charged $2,000 for a small dose of the drug. The sick woman’s husband, Heinz, went to everyone he knew to borrow the money, but he could only get together about $1,000, which is half of what it cost. He told the druggist that his wife was dying and asked him to sell it cheaper or let him pay later. But the druggist said: “No, I discovered the drug and I’m going to make money from it.” So Heinz got desperate and broke into the man’s store to steal the drug for his wife. Should the husband have done that? (Kohlberg, 1969, p. 379)

How would you answer this dilemma? Kohlberg was not interested in whether you answer yes or no to the dilemma: Instead, he was interested in the reasoning behind your answer.

After presenting people with this and various other moral dilemmas, Kohlberg reviewed people’s responses and placed them in different [pb_glossary id="2815"]stages of moral reasoning (Figure 6). According to Kohlberg, an individual progresses from the capacity for pre-conventional morality (before age 9) to the capacity for conventional morality (early adolescence), and toward attaining post-conventional morality (once formal operational thought is attained), which only a few fully achieve. Kohlberg placed in the highest stage responses that reflected the reasoning that Heinz should steal the drug because his wife’s life is more important than the pharmacist making money. The value of a human life overrides the pharmacist’s greed.

Nine boxes are arranged in rows and columns of three. The top left box contains “Level 1, Pre-conventional Morality.” A line connects this box with another box to the right containing “Stage 1, Obedience and punishment: behavior driven by avoiding punishment.” To the right is another box connected by a line containing “Stage 2, Individual interest: behavior driven by self-interest and rewards.” The middle left box contains “Level 2, Conventional Morality.” A line connects this box with another box to the right containing “Stage 3, Interpersonal: behavior driven by social approval.” To the right is another box connected by a line containing “Stage 4, Authority: behavior driven by obeying authority and conforming to social order.” The lower left box contains “Level 3, Post-conventional Morality.” A line connects this box with another box to the right containing “Stage 5, Social contract: behavior driven by balance of social order and individual rights.” To the right is another box connected by a line containing “Stage 6, Universal ethics: behavior driven by internal moral principles.”

It is important to realize that even those people who have the most sophisticated, post-conventional reasons for some choices may make other choices for the simplest of pre-conventional reasons. Many psychologists agree with Kohlberg's theory of moral development but point out that moral reasoning is very different from moral behavior. Sometimes what we say we would do in a situation is not what we actually do in that situation. In other words, we might “talk the talk,” but not “walk the walk.”

How does this theory apply to males and females? Kohlberg (1969) felt that more males than females move past stage four in their moral development. He went on to note that women seem to be deficient in their moral reasoning abilities. These ideas were not well received by Carol Gilligan, a research assistant of Kohlberg, who consequently developed her own ideas of moral development. In her groundbreaking book, In a Different Voice: Psychological Theory and Women’s Development , Gilligan (1982) criticized her former mentor’s theory because it was based only on upper class white men and boys. She argued that women are not deficient in their moral reasoning—she proposed that males and females reason differently. Girls and women focus more on staying connected and the importance of interpersonal relationships. Therefore, in the Heinz dilemma, many girls and women respond that Heinz should not steal the medicine. Their reasoning is that if he steals the medicine, is arrested, and is put in jail, then he and his wife will be separated, and she could die while he is still in prison.

Development in Childhood

Think about the miraculous development that occurs during childhood in order for a tiny zygote to grow into a walking, talking, thinking child. Newborn infants only weigh about 7.5 pounds but their physical, cognitive, and psychosocial skills grow and change as they move through developmental stages. In this section, you'll learn about many of these changes.

Describe the stages of prenatal development and the significance of prenatal care
Define and differentiate between various infant reflexes
Explain the physical, cognitive, and emotional development that occurs from infancy through childhood

Prenatal Development

As discussed at the beginning of this chapter, developmental psychologists often divide our development into three areas: physical development, cognitive development, and psychosocial development. Mirroring Erikson’s stages, lifespan development is divided into different stages that are based on age. We will discuss prenatal, infant, child, adolescent, and adult development.

Germinal Stage (Weeks 1–2)

In the discussion of biopsychology earlier in the book, you learned about genetics and DNA. A mother and father’s DNA is passed on to the child at the moment of conception. Conception occurs when sperm fertilizes an egg and forms a zygote (Figure 7). A zygote begins as a one-cell structure that is created when a sperm and egg merge. The genetic makeup and sex of the baby are set at this point. During the first week after conception, the zygote divides and multiplies, going from a one-cell structure to two cells, then four cells, then eight cells, and so on. This process of cell division is called mitosis. Mitosis is a fragile process, and fewer than one-half of all zygotes survive beyond the first two weeks (Hall, 2004). After 5 days of mitosis there are 100 cells, and after 9 months there are billions of cells. As the cells divide, they become more specialized, forming different organs and body parts. In the germinal stage, the mass of cells has yet to attach itself to the lining of the mother’s uterus. Once it does, the next stage begins.

A microscopic picture shows a single sperm fusing with the ovum.

Embryonic Stage (Weeks 3–8)

After the zygote divides for about 7–10 days and has 150 cells, it travels down the fallopian tubes and implants itself in the lining of the uterus. Upon implantation, this multi-cellular organism is called an embryo . Now blood vessels grow, forming the placenta. The placenta is a structure connected to the uterus that provides nourishment and oxygen from the mother to the developing embryo via the umbilical cord. Basic structures of the embryo start to develop into areas that will become the head, chest, and abdomen. During the embryonic stage, the heart begins to beat and organs form and begin to function. The neural tube forms along the back of the embryo, developing into the spinal cord and brain.

Fetal Stage (Weeks 9–40)

When the organism is about nine weeks old, the embryo is called a fetus. At this stage, the fetus is about the size of a kidney bean and begins to take on the recognizable form of a human being as the “tail” begins to disappear.

From 9–12 weeks, the sex organs begin to differentiate. At about 16 weeks, the fetus is approximately 4.5 inches long. Fingers and toes are fully developed, and fingerprints are visible. By the time the fetus reaches the sixth month of development (24 weeks), it weighs up to 1.4 pounds. Hearing has developed, so the fetus can respond to sounds. The internal organs, such as the lungs, heart, stomach, and intestines, have formed enough that a fetus born prematurely at this point has a chance to survive outside of the mother’s womb. Throughout the fetal stage the brain continues to grow and develop, nearly doubling in size from weeks 16 to 28. Around 36 weeks, the fetus is almost ready for birth. It weighs about 6 pounds and is about 18.5 inches long, and by week 37 all of the fetus’s organ systems are developed enough that it could survive outside the mother’s uterus without many of the risks associated with premature birth. The fetus continues to gain weight and grow in length until approximately 40 weeks. By then, the fetus has very little room to move around and birth becomes imminent. The progression through the stages is shown in Figure 8.

The growth of a fetus is shown using nine pictures in different stages of development. For each stage, there is a picture of a fetus which gets progressively larger and more mature. The first stage is labeled “9 weeks; fetal stage begins.” The second stage is labeled “12 weeks; sex organs differentiate.” The third stage is labeled “16 weeks; fingers and toes develop.” The fourth stage is labeled “20 weeks; hearing begins.” The fifth stage is labeled “24 weeks; lungs begin to develop.” The sixth stage is labeled “28 weeks; brain grows rapidly.” The seventh stage is labeled “32 weeks; bones fully develop.” The eighth stage is labeled “36 weeks; muscles fully develop.” The ninth stage is labeled “40 weeks; full-term development.”

Prenatal Influences

During each prenatal stage, genetic and environmental factors can affect development. The developing fetus is completely dependent on the mother for life. It is important that the mother takes good care of herself and receives prenatal care , which is medical care during pregnancy that monitors the health of both the mother and the fetus. According to the National Institutes of Health ([NIH], 2013), routine prenatal care is important because it can reduce the risk of complications to the mother and fetus during pregnancy. In fact, women who are trying to become pregnant or who may become pregnant should discuss pregnancy planning with their doctor. They may be advised, for example, to take a vitamin containing folic acid, which helps prevent certain birth defects, or to monitor aspects of their diet or exercise routines.

A pregnant woman is lying on a table being examined by a doctor. The doctor's hands are on her belly.

Recall that when the zygote attaches to the wall of the mother’s uterus, the placenta is formed. The placenta provides nourishment and oxygen to the fetus. Most everything the mother ingests, including food, liquid, and even medication, travels through the placenta to the fetus, hence the common phrase “eating for two.” Anything the mother is exposed to in the environment affects the fetus; if the mother is exposed to something harmful, the child can show life-long effects.

A teratogen is any environmental agent—biological, chemical, or physical—that causes damage to the developing embryo or fetus. There are different types of teratogens. Alcohol and most drugs cross the placenta and affect the fetus. Alcohol is not safe to drink in any amount during pregnancy. Alcohol use during pregnancy has been found to be the leading preventable cause of mental retardation in children in the United States (Maier & West, 2001). Excessive maternal drinking while pregnant can cause fetal alcohol spectrum disorders with life-long consequences for the child ranging in severity from minor to major (Table 3). Fetal alcohol spectrum disorders (FASD) are a collection of birth defects associated with heavy consumption of alcohol during pregnancy. Physically, children with FASD may have a small head size and abnormal facial features. Cognitively, these children may have poor judgment, poor impulse control, higher rates of ADHD, learning issues, and lower IQ scores. These developmental problems and delays persist into adulthood (Streissguth et al., 2004). Based on studies conducted on animals, it also has been suggested that a mother’s alcohol consumption during pregnancy may predispose her child to like alcohol (Youngentob et al., 2007).

Smoking is also considered a teratogen because nicotine travels through the placenta to the fetus. When the mother smokes, the developing baby experiences a reduction in blood oxygen levels. According to the Centers for Disease Control and Prevention (2013), smoking while pregnant can result in premature birth, low-birth-weight infants, stillbirth, and sudden infant death syndrome (SIDS).

Heroin, cocaine, methamphetamine, almost all prescription medicines, and most over-the counter medications are also considered teratogens. Babies born with a heroin addiction need heroin just like an adult addict. The child will need to be gradually weaned from the heroin under medical supervision; otherwise, the child could have seizures and die. Other teratogens include radiation, viruses such as HIV and herpes, and rubella (German measles). Women in the United States are much less likely to be afflicted with rubella because most women received childhood immunizations or vaccinations that protect the body from disease.

Each organ of the fetus develops during a specific period in the pregnancy, called the critical or sensitive period (Figure 9). For example, research with primate models of FASD has demonstrated that the time during which a developing fetus is exposed to alcohol can dramatically affect the appearance of facial characteristics associated with fetal alcohol syndrome. Specifically, this research suggests that alcohol exposure that is limited to day 19 or 20 of gestation can lead to significant facial abnormalities in the offspring (Ashley, Magnuson, Omnell, & Clarren, 1999). Given regions of the brain also show sensitive periods during which they are most susceptible to the teratogenic effects of alcohol (Tran & Kelly, 2003).

Dig Deeper: Should Women Who Use Drugs During Pregnancy Be Arrested and Jailed?

As you now know, women who use drugs or alcohol during pregnancy can cause serious lifelong harm to their child. Some people have advocated mandatory screenings for women who are pregnant and have a history of drug abuse, and if the women continue using, to arrest, prosecute, and incarcerate them (Figdor & Kaeser, 1998). This policy was tried in Charleston, South Carolina, as recently as 20 years ago. The policy was called the Interagency Policy on Management of Substance Abuse During Pregnancy, and had disastrous results.

The Interagency Policy applied to patients attending the obstetrics clinic at MUSC, which primarily serves patients who are indigent or on Medicaid. It did not apply to private obstetrical patients. The policy required patient education about the harmful effects of substance abuse during pregnancy. . . . [A] statement also warned patients that protection of unborn and newborn children from the harms of illegal drug abuse could involve the Charleston police, the Solicitor of the Ninth Judicial Court, and the Protective Services Division of the Department of Social Services (DSS). (Jos, Marshall, & Perlmutter, 1995, pp. 120–121)

This policy seemed to deter women from seeking prenatal care, deterred them from seeking other social services, and was applied solely to low-income women, resulting in lawsuits. The program was canceled after 5 years, during which 42 women were arrested. A federal agency later determined that the program involved human experimentation without the approval and oversight of an institutional review board (IRB). What were the flaws in the program and how would you correct them? What are the ethical implications of charging pregnant women with child abuse?

Infancy through Childhood

The average newborn weighs approximately 7.5 pounds. Although small, a newborn is not completely helpless because his reflexes and sensory capacities help him interact with the environment from the moment of birth. All healthy babies are born with newborn reflexes : inborn automatic responses to particular forms of stimulation. Reflexes help the newborn survive until it is capable of more complex behaviors—these reflexes are crucial to survival. They are present in babies whose brains are developing normally and usually disappear around 4–5 months old. Let’s take a look at some of these newborn reflexes. The rooting reflex is the newborn’s response to anything that touches her cheek: When you stroke a baby’s cheek, she naturally turns her head in that direction and begins to suck. The sucking reflex is the automatic, unlearned, sucking motions that infants do with their mouths. Several other interesting newborn reflexes can be observed. For instance, if you put your finger into a newborn’s hand, you will witness the grasping reflex , in which a baby automatically grasps anything that touches his palms. The Moro reflex is the newborn’s response when she feels like she is falling. The baby spreads her arms, pulls them back in, and then (usually) cries. How do you think these reflexes promote survival in the first months of life?

Take a few minutes to view this brief video clip illustrating several newborn reflexes .

If you are interested in learning more about human development in babies, watch this TED talk by Alison Gopnik . Recent discoveries reveal that babies are probably smarter than we think.

What can young infants see, hear, and smell? Newborn infants’ sensory abilities are significant, but their senses are not yet fully developed. Many of a newborn’s innate preferences facilitate interaction with caregivers and other humans. Although vision is their least developed sense, newborns already show a preference for faces. Babies who are just a few days old also prefer human voices, they will listen to voices longer than sounds that do not involve speech (Vouloumanos & Werker, 2004), and they seem to prefer their mother’s voice over a stranger’s voice (Mills & Melhuish, 1974). In an interesting experiment, 3-week-old babies were given pacifiers that played a recording of the infant’s mother’s voice and of a stranger’s voice. When the infants heard their mother’s voice, they sucked more strongly at the pacifier (Mills & Melhuish, 1974). Newborns also have a strong sense of smell. For instance, newborn babies can distinguish the smell of their own mother from that of others. In a study by MacFarlane (1978), 1-week-old babies who were being breastfed were placed between two gauze pads. One gauze pad was from the bra of a nursing mother who was a stranger, and the other gauze pad was from the bra of the infant’s own mother. More than two-thirds of the week-old babies turned toward the gauze pad with their mother’s scent.

Physical Development

In infancy, toddlerhood, and early childhood, the body’s physical development is rapid (Figure 10). On average, newborns weigh between 5 and 10 pounds, and a newborn’s weight typically doubles in six months and triples in one year. By 2 years old the weight will have quadrupled, so we can expect that a 2 year old should weigh between 20 and 40 pounds. The average length of a newborn is 19.5 inches, increasing to 29.5 inches by 12 months and 34.4 inches by 2 years old (WHO Multicentre Growth Reference Study Group, 2006).

A collage of four photographs depicting babies is shown. From left to right they get progressively older. The far left photograph is a bundled up sleeping newborn. To the right is a picture of a toddler next to a toy giraffe. To the right is a baby blowing out a single candle. To the far right is a child on a swing set.

During infancy and childhood, growth does not occur at a steady rate (Carel, Lahlou, Roger, & Chaussain, 2004). Growth slows between 4 and 6 years old: During this time children gain 5–7 pounds and grow about 2–3 inches per year. Once girls reach 8–9 years old, their growth rate outpaces that of boys due to a pubertal growth spurt. This growth spurt continues until around 12 years old, coinciding with the start of the menstrual cycle. By 10 years old, the average girl weighs 88 pounds, and the average boy weighs 85 pounds.

We are born with all of the brain cells that we will ever have—about 100–200 billion neurons (nerve cells) whose function is to store and transmit information (Huttenlocher & Dabholkar, 1997). However, the nervous system continues to grow and develop. Each neural pathway forms thousands of new connections during infancy and toddlerhood. This period of rapid neural growth is called blooming. Neural pathways continue to develop through puberty. The blooming period of neural growth is then followed by a period of pruning, where neural connections are reduced. It is thought that pruning causes the brain to function more efficiently, allowing for mastery of more complex skills (Hutchinson, 2011). Blooming occurs during the first few years of life, and pruning continues through childhood and into adolescence in various areas of the brain.

The size of our brains increases rapidly. For example, the brain of a 2-year-old is 55% of its adult size, and by 6 years old the brain is about 90% of its adult size (Tanner, 1978). During early childhood (ages 3–6), the frontal lobes grow rapidly. Recalling our discussion of the 4 lobes of the brain earlier in this book, the frontal lobes are associated with planning, reasoning, memory, and impulse control. Therefore, by the time children reach school age, they are developmentally capable of controlling their attention and behavior. Through the elementary school years, the frontal, temporal, occipital, and parietal lobes all grow in size. The brain growth spurts experienced in childhood tend to follow Piaget’s sequence of cognitive development, so that significant changes in neural functioning account for cognitive advances (Kolb & Whishaw, 2009; Overman, Bachevalier, Turner, & Peuster, 1992).

Motor development occurs in an orderly sequence as infants move from reflexive reactions (e.g., sucking and rooting) to more advanced motor functioning. For instance, babies first learn to hold their heads up, then to sit with assistance, and then to sit unassisted, followed later by crawling and then walking.

Motor skills refer to our ability to move our bodies and manipulate objects. Fine motor skills focus on the muscles in our fingers, toes, and eyes, and enable coordination of small actions (e.g., grasping a toy, writing with a pencil, and using a spoon). Gross motor skills focus on large muscle groups that control our arms and legs and involve larger movements (e.g., balancing, running, and jumping).

As motor skills develop, there are certain developmental milestones that young children should achieve (Table 4). For each milestone there is an average age, as well as a range of ages in which the milestone should be reached. An example of a developmental milestone is sitting. On average, most babies sit alone at 7 months old. Sitting involves both coordination and muscle strength, and 90% of babies achieve this milestone between 5 and 9 months old. In another example, babies on average are able to hold up their head at 6 weeks old, and 90% of babies achieve this between 3 weeks and 4 months old. If a baby is not holding up his head by 4 months old, he is showing a delay. If the child is displaying delays on several milestones, that is reason for concern, and the parent or caregiver should discuss this with the child’s pediatrician. Some developmental delays can be identified and addressed through early intervention.

Cognitive Development

In addition to rapid physical growth, young children also exhibit significant development of their cognitive abilities. Piaget thought that children’s ability to understand objects—such as learning that a rattle makes a noise when shaken—was a cognitive skill that develops slowly as a child matures and interacts with the environment. Today, developmental psychologists think Piaget was incorrect. Researchers have found that even very young children understand objects and how they work long before they have experience with those objects (Baillargeon, 1987; Baillargeon, Li, Gertner, & Wu, 2011). For example, children as young as 3 months old demonstrated knowledge of the properties of objects that they had only viewed and did not have prior experience with them. In one study, 3-month-old infants were shown a truck rolling down a track and behind a screen. The box, which appeared solid but was actually hollow, was placed next to the track. The truck rolled past the box as would be expected. Then the box was placed on the track to block the path of the truck. When the truck was rolled down the track this time, it continued unimpeded. The infants spent significantly more time looking at this impossible event (Figure 11). Baillargeon (1987) concluded that they knew solid objects cannot pass through each other. Baillargeon’s findings suggest that very young children have an understanding of objects and how they work, which Piaget (1954) would have said is beyond their cognitive abilities due to their limited experiences in the world.

Image A shows a toy truck coasting along a track unobstructed. Image B shows a toy truck coasting along a track with a box in the background. Image C shows a truck coasting along a track and going through what appears to be an obstruction.

Just as there are physical milestones that we expect children to reach, there are also cognitive milestones. It is helpful to be aware of these milestones as children gain new abilities to think, problem solve, and communicate. For example, infants shake their head “no” around 6–9 months, and they respond to verbal requests to do things like “wave bye-bye” or “blow a kiss” around 9–12 months. Remember Piaget’s ideas about object permanence? We can expect children to grasp the concept that objects continue to exist even when they are not in sight by around 8 months old. Because toddlers (i.e., 12–24 months old) have mastered object permanence, they enjoy games like hide and seek, and they realize that when someone leaves the room they will come back (Loop, 2013). Toddlers also point to pictures in books and look in appropriate places when you ask them to find objects.

Preschool-age children (i.e., 3–5 years old) also make steady progress in cognitive development. Not only can they count, name colors, and tell you their name and age, but they can also make some decisions on their own, such as choosing an outfit to wear. Preschool-age children understand basic time concepts and sequencing (e.g., before and after), and they can predict what will happen next in a story. They also begin to enjoy the use of humor in stories. Because they can think symbolically, they enjoy pretend play and inventing elaborate characters and scenarios. One of the most common examples of their cognitive growth is their blossoming curiosity. Preschool-age children love to ask “Why?”

An important cognitive change occurs in children this age. Recall that Piaget described 2–3 year olds as egocentric, meaning that they do not have an awareness of others’ points of view. Between 3 and 5 years old, children come to understand that people have thoughts, feelings, and beliefs that are different from their own. This is known as theory-of-mind (TOM). Children can use this skill to tease others, persuade their parents to purchase a candy bar, or understand why a sibling might be angry. When children develop TOM, they can recognize that others have false beliefs (Dennett, 1987; Callaghan et al., 2005).

False-belief tasks are useful in determining a child’s acquisition of theory-of-mind (TOM). Take a look at this video clip showing a false-belief task involving a box of crayons.

You can view the transcript for "The "False Belief" Test: Theory of Mind" here (opens in new window) .

Cognitive skills continue to expand in middle and late childhood (6–11 years old). Thought processes become more logical and organized when dealing with concrete information (Figure 12). Children at this age understand concepts such as the past, present, and future, giving them the ability to plan and work toward goals. Additionally, they can process complex ideas such as addition and subtraction and cause-and-effect relationships. However, children’s attention spans tend to be very limited until they are around 11 years old. After that point, it begins to improve through adulthood.

A photograph of children playing baseball is shown. Five children are in the picture, two on one team, and three on the other.

One well-researched aspect of cognitive development is language acquisition. As mentioned earlier, the order in which children learn language structures is consistent across children and cultures (Hatch, 1983). You’ve also learned that some psychological researchers have proposed that children possess a biological predisposition for language acquisition.

Starting before birth, babies begin to develop language and communication skills. At birth, babies apparently recognize their mother’s voice and can discriminate between the language(s) spoken by their mothers and foreign languages, and they show preferences for faces that are moving in synchrony with audible language (Blossom & Morgan, 2006; Pickens, 1994; Spelke & Cortelyou, 1981).

Children communicate information through gesturing long before they speak, and there is some evidence that gesture usage predicts subsequent language development (Iverson & Goldin-Meadow, 2005). In terms of producing spoken language, babies begin to coo almost immediately. Cooing is a one-syllable combination of a consonant and a vowel sound (e.g., coo or ba). Interestingly, babies replicate sounds from their own languages. A baby whose parents speak French will coo in a different tone than a baby whose parents speak Spanish or Urdu. After cooing, the baby starts to babble. Babbling begins with repeating a syllable, such as ma-ma, da-da, or ba-ba. When a baby is about 12 months old, we expect her to say her first word for meaning, and to start combining words for meaning at about 18 months.

At about 2 years old, a toddler uses between 50 and 200 words; by 3 years old they have a vocabulary of up to 1,000 words and can speak in sentences. During the early childhood years, children's vocabulary increases at a rapid pace. This is sometimes referred to as the “vocabulary spurt” and has been claimed to involve an expansion in vocabulary at a rate of 10–20 new words per week. Recent research may indicate that while some children experience these spurts, it is far from universal (as discussed in Ganger & Brent, 2004). It has been estimated that, 5 year olds understand about 6,000 words, speak 2,000 words, and can define words and question their meanings. They can rhyme and name the days of the week. Seven year olds speak fluently and use slang and clichés (Stork & Widdowson, 1974).

What accounts for such dramatic language learning by children? Behaviorist B. F. Skinner thought that we learn language in response to reinforcement or feedback, such as through parental approval or through being understood. For example, when a two-year-old child asks for juice, he might say, “me juice,” to which his mother might respond by giving him a cup of apple juice. Noam Chomsky (1957) criticized Skinner’s theory and proposed that we are all born with an innate capacity to learn language. Chomsky called this mechanism a language acquisition device (LAD). Who is correct? Both Chomsky and Skinner are right. Remember that we are a product of both nature and nurture. Researchers now believe that language acquisition is partially inborn and partially learned through our interactions with our linguistic environment (Gleitman & Newport, 1995; Stork & Widdowson, 1974).

Everyday Connection: The Importance of Play and Recess

According to the American Academy of Pediatrics (2007), unstructured play is an integral part of a child’s development. It builds creativity, problem solving skills, and social relationships. Play also allows children to develop a theory-of-mind as they imaginatively take on the perspective of others.

Outdoor play allows children the opportunity to directly experience and sense the world around them. While doing so, they may collect objects that they come across and develop lifelong interests and hobbies. They also benefit from increased exercise, and engaging in outdoor play can actually increase how much they enjoy physical activity. This helps support the development of a healthy heart and brain. Unfortunately, research suggests that today’s children are engaging in less and less outdoor play (Clements, 2004). Perhaps, it is no surprise to learn that lowered levels of physical activity in conjunction with easy access to calorie-dense foods with little nutritional value are contributing to alarming levels of childhood obesity (Karnik & Kanekar, 2012).

Despite the adverse consequences associated with reduced play, some children are over scheduled and have little free time to engage in unstructured play. In addition, some schools have taken away recess time for children in a push for students to do better on standardized tests, and many schools commonly use loss of recess as a form of punishment. Do you agree with these practices? Why or why not?

Psychosocial development occurs as children form relationships, interact with others, and understand and manage their feelings. In social and emotional development, forming healthy attachments is very important and is the major social milestone of infancy. Attachment is a long-standing connection or bond with others. Developmental psychologists are interested in how infants reach this milestone. They ask such questions as: How do parent and infant attachment bonds form? How does neglect affect these bonds? What accounts for children’s attachment differences?

Building on the work of Harlow and others, John Bowlby developed the concept of attachment theory. He defined attachment as the affectional bond or tie that an infant forms with the mother (Bowlby, 1969). An infant must form this bond with a primary caregiver in order to have normal social and emotional development. In addition, Bowlby proposed that this attachment bond is very powerful and continues throughout life. He used the concept of secure base to define a healthy attachment between parent and child (1988). A secure base is a parental presence that gives the child a sense of safety as he explores his surroundings. Bowlby said that two things are needed for a healthy attachment: The caregiver must be responsive to the child’s physical, social, and emotional needs; and the caregiver and child must engage in mutually enjoyable interactions (Bowlby, 1969) (Figure 13).

While Bowlby thought attachment was an all-or-nothing process, Mary Ainsworth’s (1970) research showed otherwise. Ainsworth wanted to know if children differ in the ways they bond, and if so, why. To find the answers, she used the Strange Situation procedure to study attachment between mothers and their infants (1970). In the Strange Situation, the mother (or primary caregiver) and the infant (age 12-18 months) are placed in a room together. There are toys in the room, and the caregiver and child spend some time alone in the room. After the child has had time to explore her surroundings, a stranger enters the room. The mother then leaves her baby with the stranger. After a few minutes, she returns to comfort her child.

Based on how the infants/toddlers responded to the separation and reunion, Ainsworth identified three types of parent-child attachments: secure, avoidant, and resistant (Ainsworth & Bell, 1970). A fourth style, known as disorganized attachment, was later described (Main & Solomon, 1990). The most common type of attachment—also considered the healthiest—is called secure attachment (Figure 14). In this type of attachment, the toddler prefers his parent over a stranger. The attachment figure is used as a secure base to explore the environment and is sought out in times of stress. Securely attached children were distressed when their caregivers left the room in the Strange Situation experiment, but when their caregivers returned, the securely attached children were happy to see them. Securely attached children have caregivers who are sensitive and responsive to their needs.

A photograph shows a person squatting down next to a small child who is standing up.

With avoidant attachment (sometimes called insecure or anxious-avoidant), the child is unresponsive to the parent, does not use the parent as a secure base, and does not care if the parent leaves. The toddler reacts to the parent the same way she reacts to a stranger. When the parent does return, the child is slow to show a positive reaction. Ainsworth theorized that these children were most likely to have a caregiver who was insensitive and inattentive to their needs (Ainsworth, Blehar, Waters, & Wall, 1978).

In cases of resistant attachment (also called ambivalent or anxious-ambivalent/resistant), children tend to show clingy behavior, but then they reject the attachment figure’s attempts to interact with them (Ainsworth & Bell, 1970). These children do not explore the toys in the room, as they are too fearful. During separation in the Strange Situation, they became extremely disturbed and angry with the parent. When the parent returns, the children are difficult to comfort. Resistant attachment is the result of the caregivers’ inconsistent level of response to their child.

Finally, children with disorganized attachment behaved oddly in the Strange Situation. They freeze, run around the room in an erratic manner, or try to run away when the caregiver returns (Main & Solomon, 1990). This type of attachment is seen most often in kids who have been abused. Research has shown that abuse disrupts a child’s ability to regulate their emotions.

While Ainsworth’s research has found support in subsequent studies, it has also met criticism. Some researchers have pointed out that a child’s temperament may have a strong influence on attachment (Gervai, 2009; Harris, 2009), and others have noted that attachment varies from culture to culture, a factor not accounted for in Ainsworth’s research (Rothbaum, Weisz, Pott, Miyake, & Morelli, 2000; van Ijzendoorn & Sagi-Schwartz, 2008).

Watch this video to view a clip of the Strange Situation. Try to identify which type of attachment baby Lisa exhibits.

You can view the transcript for "The Strange Situation - Mary Ainsworth" here (opens in new window) .

Self-Concept

Just as attachment is the main psychosocial milestone of infancy, the primary psychosocial milestone of childhood is the development of a positive sense of self. How does self-awareness develop? Infants don’t have a self-concept, which is an understanding of who they are. If you place a baby in front of a mirror, she will reach out to touch her image, thinking it is another baby. However, by about 18 months a toddler will recognize that the person in the mirror is herself. How do we know this? In a well-known experiment, a researcher placed a red dot of paint on children’s noses before putting them in front of a mirror (Amsterdam, 1972). Commonly known as the mirror test, this behavior is demonstrated by humans and a few other species and is considered evidence of self-recognition (Archer, 1992). At 18 months old they would touch their own noses when they saw the paint, surprised to see a spot on their faces. By 24–36 months old children can name and/or point to themselves in pictures, clearly indicating self-recognition.

Children from 2–4 years old display a great increase in social behavior once they have established a self-concept. They enjoy playing with other children, but they have difficulty sharing their possessions. Also, through play children explore and come to understand their gender roles and can label themselves as a girl or boy (Chick, Heilman-Houser, & Hunter, 2002). By 4 years old, children can cooperate with other children, share when asked, and separate from parents with little anxiety. Children at this age also exhibit autonomy, initiate tasks, and carry out plans. Success in these areas contributes to a positive sense of self. Once children reach 6 years old, they can identify themselves in terms of group memberships: “I’m a first grader!” School-age children compare themselves to their peers and discover that they are competent in some areas and less so in others (recall Erikson’s task of industry versus inferiority). At this age, children recognize their own personality traits as well as some other traits they would like to have. For example, 10-year-old Layla says, “I’m kind of shy. I wish I could be more talkative like my friend Alexa.”

Development of a positive self-concept is important to healthy development. Children with a positive self-concept tend to be more confident, do better in school, act more independently, and are more willing to try new activities (Maccoby, 1980; Ferrer & Fugate, 2003). Formation of a positive self-concept begins in Erikson’s toddlerhood stage, when children establish autonomy and become confident in their abilities. Development of self-concept continues in elementary school, when children compare themselves to others. When the comparison is favorable, children feel a sense of competence and are motivated to work harder and accomplish more. Self-concept is re-evaluated in Erikson’s adolescence stage, as teens form an identity. They internalize the messages they have received regarding their strengths and weaknesses, keeping some messages and rejecting others. Adolescents who have achieved identity formation are capable of contributing positively to society (Erikson, 1968).

What can parents do to nurture a healthy self-concept? Diana Baumrind (1971, 1991) thinks parenting style may be a factor. The way we parent is an important factor in a child’s socioemotional growth. Baumrind developed and refined a theory describing four parenting styles: authoritative, authoritarian, permissive, and uninvolved. With the authoritative style , the parent gives reasonable demands and consistent limits, expresses warmth and affection, and listens to the child’s point of view. Parents set rules and explain the reasons behind them. They are also flexible and willing to make exceptions to the rules in certain cases—for example, temporarily relaxing bedtime rules to allow for a nighttime swim during a family vacation. Of the four parenting styles, the authoritative style is the one that is most encouraged in modern American society. American children raised by authoritative parents tend to have high self-esteem and social skills. However, effective parenting styles vary as a function of culture and, as Small (1999) points out, the authoritative style is not necessarily preferred or appropriate in all cultures.

In authoritarian style , the parent places high value on conformity and obedience. The parents are often strict, tightly monitor their children, and express little warmth. In contrast to the authoritative style, authoritarian parents probably would not relax bedtime rules during a vacation because they consider the rules to be set, and they expect obedience. This style can create anxious, withdrawn, and unhappy kids. However, it is important to point out that authoritarian parenting is as beneficial as the authoritative style in some ethnic groups (Russell, Crockett, & Chao, 2010). For instance, first-generation Chinese American children raised by authoritarian parents did just as well in school as their peers who were raised by authoritative parents (Russell et al., 2010).

For parents who employ the permissive style of parenting, the kids run the show and anything goes. Permissive parents make few demands and rarely use punishment. They tend to be very nurturing and loving, and may play the role of friend rather than parent. In terms of our example of vacation bedtimes, permissive parents might not have bedtime rules at all—instead they allow the child to choose his bedtime whether on vacation or not. Not surprisingly, children raised by permissive parents tend to lack self-discipline, and the permissive parenting style is negatively associated with grades (Dornbusch, Ritter, Leiderman, Roberts, & Fraleigh, 1987). The permissive style may also contribute to other risky behaviors such as alcohol abuse (Bahr & Hoffman, 2010), risky sexual behavior especially among female children (Donenberg, Wilson, Emerson, & Bryant, 2002), and increased display of disruptive behaviors by male children (Parent et al., 2011). However, there are some positive outcomes associated with children raised by permissive parents. They tend to have higher self-esteem, better social skills, and report lower levels of depression (Darling, 1999).

With the uninvolved style of parenting, the parents are indifferent, uninvolved, and sometimes referred to as neglectful. They don’t respond to the child’s needs and make relatively few demands. This could be because of severe depression or substance abuse, or other factors such as the parents’ extreme focus on work. These parents may provide for the child’s basic needs, but little else. The children raised in this parenting style are usually emotionally withdrawn, fearful, anxious, perform poorly in school, and are at an increased risk of substance abuse (Darling, 1999).

As you can see, parenting styles influence childhood adjustment, but could a child’s temperament likewise influence parenting? Temperament refers to innate traits that influence how one thinks, behaves, and reacts with the environment. Children with easy temperaments demonstrate positive emotions, adapt well to change, and are capable of regulating their emotions. Conversely, children with difficult temperaments demonstrate negative emotions and have difficulty adapting to change and regulating their emotions. Difficult children are much more likely to challenge parents, teachers, and other caregivers (Thomas, 1984). Therefore, it’s possible that easy children (i.e., social, adaptable, and easy to soothe) tend to elicit warm and responsive parenting, while demanding, irritable, withdrawn children evoke irritation in their parents or cause their parents to withdraw (Sanson & Rothbart, 1995).

Development in Adolescence and Adulthood

Changes in development during childhood are rapid and more obvious than the changes that come later on in life, but before you reach adulthood, there is one more large transition: adolescence. Adolescence brings the physical development of puberty, as well as cognitive, social, and emotional changes. Following adolescence, transitions are less obvious, but still significant throughout emerging adulthood and adulthood. Finally, growing older means confronting many psychological, emotional, and social issues that come with entering the last phase of life.

Watch this video from a few of the world's oldest people for some advice on how you can also live a fulfilling life until the very end.

You can view the transcript for "How to Be the Oldest Person Alive" here (opens in new window) .

Describe physical, cognitive, and emotional development that occurs during adolescence
Describe physical, cognitive, and emotional development that occurs in adulthood
Differentiate between fluid and crystallized intelligence

Adolescence

Adolescence is a socially constructed concept. In pre-industrial society, children were considered adults when they reached physical maturity, but today we have an extended time between childhood and adulthood called adolescence. Adolescence is the period of development that begins at puberty and ends at emerging adulthood, or into the mid- to late 20s. In the United States, adolescence is seen as a time to develop independence from parents while remaining connected to them (Figure 15). The typical age range of adolescence is from 12 to 18 years, and this stage of development also has some predictable physical, cognitive, and psychosocial milestones.

Several people are congregated by the beach. There is a net in the background.

As noted above, adolescence begins with puberty. While the sequence of physical changes in puberty is predictable, the onset and pace of puberty vary widely. Several physical changes occur during puberty, such as adrenarche and gonadarche, the maturing of the adrenal glands and sex glands, respectively. Also during this time, primary and secondary sexual characteristics develop and mature. Primary sexual characteristics are organs specifically needed for reproduction, like the uterus and ovaries in females and testes in males. Secondary sexual characteristics are physical signs of sexual maturation that do not directly involve sex organs, such as development of breasts and hips in girls, and development of facial hair and a deepened voice in boys. Girls experience menarche, the beginning of menstrual periods, usually around 12–13 years old, and boys experience spermarche, the first ejaculation, around 13–14 years old.

During puberty, both sexes experience a rapid increase in height (i.e., growth spurt). For girls this begins between 8 and 13 years old, with adult height reached between 10 and 16 years old. Boys begin their growth spurt slightly later, usually between 10 and 16 years old, and reach their adult height between 13 and 17 years old. Both nature (i.e., genes) and nurture (e.g., nutrition, medications, and medical conditions) can influence height.

Because rates of physical development vary so widely among teenagers, puberty can be a source of pride or embarrassment. Early maturing boys tend to be stronger, taller, and more athletic than their later maturing peers. They are usually more popular, confident, and independent, but they are also at a greater risk for substance abuse and early sexual activity (Flannery, Rowe, & Gulley, 1993; Kaltiala-Heino, Rimpela, Rissanen, & Rantanen, 2001). Early maturing girls may be teased or overtly admired, which can cause them to feel self-conscious about their developing bodies. These girls are at a higher risk for depression, substance abuse, and eating disorders (Ge, Conger, & Elder, 2001; Graber, Lewinsohn, Seeley, & Brooks-Gunn, 1997; Striegel-Moore & Cachelin, 1999). Late blooming boys and girls (i.e., they develop more slowly than their peers) may feel self-conscious about their lack of physical development. Negative feelings are particularly a problem for late maturing boys, who are at a higher risk for depression and conflict with parents (Graber et al., 1997) and more likely to be bullied (Pollack & Shuster, 2000).

The adolescent brain also remains under development. Recall from your earlier study, that the brain consists of six regions: temporal lobe, brain stem, cerebellum, occipital lobe (includes the visual cortex), parietal lobe, and the frontal lobe. The frontal lobe consists of the prefrontal cortex, premotor cortex, and motor cortex. The prefrontal lobe lies just behind the forehead. Up until puberty, brain cells continue to bloom in the frontal region. Adolescents engage in increased risk-taking behaviors and emotional outbursts possibly because the frontal lobes of their brains are still developing (Figure 16). Recall that this area is often called the "CEO of the brain", as it is responsible for judgment, impulse control, and planning. It is still maturing into early adulthood, up until around age 25 (Casey, Tottenham, Liston, & Durston, 2005).

An illustration of a brain is shown with the frontal lobe labeled.

Brain maturity occurs when there is growth of new neural connections and the pruning of unused neurons and connections. According to recent research, the brain regions tend to develop from the back to the front of the brain. Also, myelin continues to grow around axons and neurons helping to speed transmission between the various regions of the brain.

Psychosocial Development

Adolescents continue to refine their sense of self as they relate to others. Erikson referred to the task of the adolescent as one of identity versus role confusion. Thus, in Erikson’s view, an adolescent’s main questions are “Who am I?” and “Who do I want to be?” Some adolescents adopt the values and roles that their parents expect for them. Other teens develop identities that are in opposition to their parents but align with a peer group. This is common as peer relationships become a central focus in adolescents’ lives.

As adolescents work to form their identities, they pull away from their parents, and the peer group becomes very important (Shanahan, McHale, Osgood, & Crouter, 2007). Despite spending less time with their parents, most teens report positive feelings toward them (Moore, Guzman, Hair, Lippman, & Garrett, 2004). Warm and healthy parent-child relationships have been associated with positive child outcomes, such as better grades and fewer school behavior problems, in the United States as well as in other countries (Hair et al., 2005).

It appears that most teens don’t experience adolescent storm and stress to the degree once famously suggested by G. Stanley Hall, a pioneer in the study of adolescent development. Only small numbers of teens have major conflicts with their parents (Steinberg & Morris, 2001), and most disagreements are minor. For example, in a study of over 1,800 parents of adolescents from various cultural and ethnic groups, Barber (1994) found that conflicts occurred over day-to-day issues such as homework, money, curfews, clothing, chores, and friends. These types of arguments tend to decrease as teens develop (Galambos & Almeida, 1992).

Emerging Adulthood

The next stage of development is emerging adulthood . This is a relatively newly defined period of lifespan development spanning from 18 years old to the mid-20s, characterized as an in-between time where identity exploration is focused on work and love.

When does a person become an adult? There are many ways to answer this question. In the United States, you are legally considered an adult at 18 years old. But other definitions of adulthood vary widely; in sociology, for example, a person may be considered an adult when she becomes self-supporting, chooses a career, gets married, or starts a family. The ages at which we achieve these milestones vary from person to person as well as from culture to culture. For example, in the African country of Malawi, 15-year-old Njemile was married at 14 years old and had her first child at 15 years old. In her culture she is considered an adult. Children in Malawi take on adult responsibilities such as marriage and work (e.g., carrying water, tending babies, and working fields) as early as 10 years old. In stark contrast, independence in Western cultures is taking longer and longer, effectively delaying the onset of adult life.

Why is it taking twenty-somethings so long to grow up? It seems that emerging adulthood is a product of both Western culture and our current times (Arnett, 2000). People in developed countries are living longer, allowing the freedom to take an extra decade to start a career and family. Changes in the workforce also play a role. For example, 50 years ago, a young adult with a high school diploma could immediately enter the work force and climb the corporate ladder. That is no longer the case. Bachelor’s and even graduate degrees are required more and more often—even for entry-level jobs (Arnett, 2000). In addition, many students are taking longer (five or six years) to complete a college degree as a result of working and going to school at the same time. After graduation, many young adults return to the family home because they have difficulty finding a job. Changing cultural expectations may be the most important reason for the delay in entering adult roles. Young people are spending more time exploring their options, so they are delaying marriage and work as they change majors and jobs multiple times, putting them on a much later timetable than their parents (Arnett, 2000).

Adulthood begins around 20 years old and has three distinct stages: early, middle, and late. Each stage brings its own set of rewards and challenges.

By the time we reach early adulthood (20 to early 40s), our physical maturation is complete, although our height and weight may increase slightly. In young adulthood, our physical abilities are at their peak, including muscle strength, reaction time, sensory abilities, and cardiac functioning. Most professional athletes are at the top of their game during this stage. Many women have children in the young adulthood years, so they may see additional weight gain and breast changes.

Middle adulthood extends from the 40s to the 60s (Figure 18). Physical decline is gradual. The skin loses some elasticity, and wrinkles are among the first signs of aging. Visual acuity decreases during this time. Women experience a gradual decline in fertility as they approach the onset of menopause, the end of the menstrual cycle, around 50 years old. Both men and women tend to gain weight: in the abdominal area for men and in the hips and thighs for women. Hair begins to thin and turn gray.

Late adulthood is considered to extend from the 60s on. This is the last stage of physical change. The skin continues to lose elasticity, reaction time slows further, and muscle strength diminishes. Smell, taste, hearing, and vision, so sharp in our twenties, decline significantly. The brain may also no longer function at optimal levels, leading to problems like memory loss, dementia, and Alzheimer’s disease in later years.

Because we spend so many years in adulthood (more than any other stage), cognitive changes are numerous. In fact, research suggests that adult cognitive development is a complex, ever changing process that may be even more active than cognitive development in infancy and early childhood (Fischer, Yan, & Stewart, 2003).

Researchers have identified areas of both losses and gains in cognition in older age. Cognitive ability and intelligence are often measured using standardized tests and validated measures. The psychometric approach has identified two categories of intelligence that show different rates of change across the life span (Schaie & Willis, 1996). Fluid intelligence refers to information processing abilities, such as logical reasoning, remembering lists, spatial ability, and reaction time. Crystallized intelligence encompasses abilities that draw upon experience and knowledge. Measures of crystallized intelligence include vocabulary tests, solving number problems, and understanding texts.

Photograph of an older man holding a cane while getting off of his moped.

With age, systematic declines are observed on cognitive tasks requiring self-initiated, effortful processing, without the aid of supportive memory cues (Park, 2000). Older adults tend to perform poorer than young adults on memory tasks that involve recall of information, where individuals must retrieve information they learned previously without the help of a list of possible choices. For example, older adults may have more difficulty recalling facts such as names or contextual details about where or when something happened (Craik, 2000). What might explain these deficits as we age? As we age, working memory, or our ability to simultaneously store and use information, becomes less efficient (Craik & Bialystok, 2006). The ability to process information quickly also decreases with age. This slowing of processing speed may explain age differences on many different cognitive tasks (Salthouse, 2004). Some researchers have argued that inhibitory functioning, or the ability to focus on certain information while suppressing attention to less pertinent information, declines with age and may explain age differences in performance on cognitive tasks (Hasher & Zacks, 1988). Finally, it is well established that our hearing and vision decline as we age. Longitudinal research has proposed that deficits in sensory functioning explain age differences in a variety of cognitive abilities (Baltes & Lindenberger, 1997).

Fewer age differences are observed when memory cues are available, such as for recognition memory tasks, or when individuals can draw upon acquired knowledge or experience. For example, older adults often perform as well if not better than young adults on tests of word knowledge or vocabulary. With age often comes expertise, and research has pointed to areas where aging experts perform as well or better than younger individuals. For example, older typists were found to compensate for age-related declines in speed by looking farther ahead at printed text (Salthouse, 1984). Compared to younger players, older chess experts are able to focus on a smaller set of possible moves, leading to greater cognitive efficiency (Charness, 1981). Accrued knowledge of everyday tasks, such as grocery prices, can help older adults to make better decisions than young adults (Tentori, Osheron, Hasher, & May, 2001).

How do changes or maintenance of cognitive ability affect older adults’ everyday lives? Researchers have studied cognition in the context of several different everyday activities. One example is driving. Although older adults often have more years of driving experience, cognitive declines related to reaction time or attentional processes may pose limitations under certain circumstances (Park & Gutchess, 2000). Research on interpersonal problem solving suggested that older adults use more effective strategies than younger adults to navigate through social and emotional problems (Blanchard-Fields, 2007). In the context of work, researchers rarely find that older individuals perform poorer on the job (Park & Gutchess, 2000). Similar to everyday problem solving, older workers may develop more efficient strategies and rely on expertise to compensate for cognitive decline.

How can we delay the onset of cognitive decline? Mental and physical activity seems to play a part (Figure 20). Research has found adults who engage in mentally and physically stimulating activities experience less cognitive decline and have a reduced incidence of mild cognitive impairment and dementia (Hertzog, Kramer, Wilson, & Lindenberger, 2009; Larson et al., 2006; Podewils et al., 2005).

There are many theories about the social and emotional aspects of aging. Some aspects of healthy aging include activities, social connectedness, and the role of a person’s culture. According to many theorists, including George Vaillant (2002), who studied and analyzed over 50 years of data, we need to have and continue to find meaning throughout our lives. For those in early and middle adulthood, meaning is found through work (Sterns & Huyck, 2001) and family life (Markus, Ryff, Curan, & Palmersheim, 2004). These areas relate to the tasks that Erikson referred to as intimacy versus isolation in early adulthood and generativity versus stagnation in middle adulthood. As mentioned previously, adults tend to define themselves by what they do—their careers. Earnings peak during this time, yet job satisfaction is more closely tied to work that involves contact with other people, is interesting, provides opportunities for advancement, and allows some independence (Mohr & Zoghi, 2006) than it is to salary (Iyengar, Wells, & Schwartz, 2006). How might being unemployed or being in a dead-end job challenge adult well-being?

As people enter the final stages of life, they have what Erik Erikson described as a crisis over integrity versus despair. In other words, they review the events of their lives and try to come to terms with the mark (or lack thereof) that they have made on the world. People who believe they have had a positive impact on the world through their contributions live the end of life with a sense of integrity. Those who feel they have not measured up to certain standards—either their own or others'—develop a sense of despair.

Positive relationships with significant others in our adult years have been found to contribute to a state of well-being (Ryff & Singer, 2009). Most adults in the United States identify themselves through their relationships with family—particularly with spouses, children, and parents (Markus et al., 2004). While raising children can be stressful, especially when they are young, research suggests that parents reap the rewards down the road, as adult children tend to have a positive effect on parental well-being (Umberson, Pudrovska, & Reczek, 2010). Having a stable marriage has also been found to contribute to well-being throughout adulthood (Vaillant, 2002).

Another aspect of positive aging is believed to be social connectedness and social support. As we get older, socioemotional selectivity theory suggests that our social support and friendships dwindle in number, but remain as close, if not more close than in our earlier years (Carstensen, 1992) (Figure 21).

Putting It Together: Lifespan Development

In this chapter, you learned to

compare and contrast theories lifespan development theories
explain the physical, cognitive, and emotional development that occurs from infancy through childhood
describe physical, cognitive, and emotional development in adolescence and adulthood

Our understanding of human nature has come a long way since the belief that children were just little adults in need of instruction. Through ongoing research, we now know that children hit certain milestones that enable them to take another viewpoint or understand the law of conservation, that babies can understand enough about the world around them to make moral judgments, and that issues of physical, social, and cognitive importance change across the lifespan.

Adolescence is one of the time periods of interest to psychologists, especially due to the focus on identity formation, which often involves a period of exploration followed by commitments to particular identities. Adolescence is characterized by risky behavior, which is made more likely by changes in the brain in which reward-processing centers develop more rapidly than cognitive control systems, making adolescents more sensitive to rewards than to possible negative consequences.

Marcia (1966) described identify formation during adolescence as involving both decision points and commitments with respect to ideologies (e.g., religion, politics) and occupations. He described four identity statuses: foreclosure, identity diffusion, moratorium, and identity achievement.

Foreclosure occurs when an individual commits to an identity without exploring options.
Identity diffusion occurs when adolescents neither explore nor commit to any identities.
Moratorium is a state in which adolescents are actively exploring options but have not yet made commitments.
Identity achievement occurs when individuals have explored different options and then made identity commitments.

Think about your own adolescent experience (you may consider yourself still in this life stage). Which identity status best fits with your own experience? Do you feel committed to your current identity, or do you feel as though you are still developing? Regardless of your answer, you can rest assured that human development does not end with adolescence, and research proves that people can continue to learn, grow, and even change as long as they would like.

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study of development using norms, or average ages, when most children reach specific developmental milestones

all of the beliefs, customs, art, and traditions of a particular society

view that development is a cumulative process: gradually improving on existing skills

view that development takes place in unique stages, which happen at specific times or ages

process proposed by Freud in which pleasure-seeking urges focus on different erogenous zones of the body as humans move through five stages of life

domain of lifespan development that examines emotions, personality, and social relationships from infancy through adulthood, proposed by Erikson

(plural = schemata) mental construct consisting of a cluster or collection of related concepts

adjustment of a schema by adding information similar to what is already known

adjustment of a schema by changing a scheme to accommodate new information different from what was already known

idea that even if something is out of sight, it still exists

second stage in Piaget’s theory of cognitive development; from ages 2 to 7, children learn to use symbols and language but do not understand mental operations and often think illogically

idea that even if you change the appearance of something, it is still equal in size, volume, or number as long as nothing is added or removed

preoperational child’s difficulty in taking the perspective of others

third stage in Piaget’s theory of cognitive development; from about 7 to 11 years old, children can think logically about real (concrete) events

principle that objects can be changed, but then returned back to their original form or condition

structure created when a sperm and egg merge at conception; begins as a single cell and rapidly divides to form the embryo and placenta

multi-cellular organism in its early stages of development

structure connected to the uterus that provides nourishment and oxygen to the developing baby

medical care during pregnancy that monitors the health of both the mother and the fetus

time during fetal growth when specific parts or organs develop

inborn automatic response to a particular form of stimulation that all healthy babies are born with

ability to move our body and manipulate objects

use of muscles in fingers, toes, and eyes to coordinate small actions

use of large muscle groups to control arms and legs for large body movements

long-standing connection or bond with others

parental presence that gives the infant/toddler a sense of safety as they explore their surroundings

characterized by the child using the parent as a secure base from which to explore

characterized by child’s unresponsiveness to parent, does not use the parent as a secure base, and does not care if parent leaves

characterized by the child’s tendency to show clingy behavior and rejection of the parent when they attempt to interact with the child

characterized by the child’s odd behavior when faced with the parent; type of attachment seen most often with kids that are abused

parents give children reasonable demands and consistent limits, express warmth and affection, and listen to the child’s point of view

parents place a high value on conformity and obedience, are often rigid, and express little warmth to the child

parents make few demands and rarely use punishment

parents are indifferent, uninvolved, and sometimes referred to as neglectful; they don’t respond to the child’s needs and make relatively few demands

period of development that begins at puberty and ends at early adulthood

newly defined period of lifespan development from 18 years old to the mid-20s; young people are taking longer to complete college, get a job, get married, and start a family

information processing abilities, such as logical reasoning, remembering lists, spatial ability, and reaction time

intelligence that draw upon experience and knowledge. Measures include vocabulary tests, solving number problems, and understanding texts

Psychological Science: Understanding Human Behavior Copyright © by Karenna Malavanti is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License , except where otherwise noted.

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Intro to Lifespan Development

Why study lifespan development.

Three generations of women in a family: young adult, middle-aged mother, and older grandmother.

Welcome to the study of lifespan development! This is the scientific study of how and why people change or remain the same over time.

Think about how you were five, ten, or even fifteen years ago. In what ways have you changed? In what ways have you remained the same? You have probably changed physically; perhaps you’ve grown taller and become heavier. But you may have also experienced changes in the way you think and solve problems. Cognitive change is noticeable when we compare how 6-year olds, 16-year olds, and 46-year olds think and reason, for example. Their thoughts about themselves, others, and the world are probably quite different. Consider friendship—a 6-year-old may think that a friend is someone with whom they can play and have fun. A 16-year old may seek friends who can help them gain status or popularity. And the 46-year old may have acquaintances, but rely more on family members to do things with and confide in. You may have also experienced psychosocial change. This refers to emotions and psychological issues as well as social roles and relationships. Psychologist Erik Erikson suggests that we struggle with issues of trust, independence, and intimacy at various points in our lives (we will explore this thoroughly throughout the course.)

This is a very interesting and meaningful course because it is about each of us and those with whom we live and work. One of the best ways to gain perspective on our own lives is to compare our experiences with those of others. In this course, we will strive to learn about each phase of human development and the physical, cognitive, and psychosocial changes, all the while making cross-cultural and historical comparisons and connections to the world around us.

In addition, we will take a lifespan developmental approach to learn about human development. That means that we won’t just learn about one particular age period by itself; we will learn about each age period, recognizing how it is related to both previous developments and later developments. For instance, it helps us to understand what’s happening with the 16-year old by knowing about development in the infant, toddler, early childhood, and middle childhood years. In turn, learning about all of that development and development during adolescence and early adulthood will help us to more fully understand the person at age 46 (and so on throughout midlife and later adulthood).

Development does not stop at a certain age; development is a lifelong process. We may find individual and group differences in patterns of development, so examining the influences of gender, cohort/generation, race, ethnicity, culture, socioeconomic status, education level, and time in history is also important. With the lifespan developmental perspective, we will gain a more comprehensive view of the individual within the context of their own developmental journey and within social, cultural, and historical contexts. In this way, this course covers and crosses multiple disciplines, such as psychology, biology, sociology, anthropology, education, nutrition, economics, and healthcare.

Think It Over

Wherever you are in your own lifespan developmental journey, imagine yourself as an elderly person about to turn 100 years old (becoming a “centenarian”). If researchers want to understand you and your development, would they get the full picture if they just took a snapshot (so to speak) of you at that point in time? What else would you want them to know about you, your development, and your experiences to really understand you?

What you’ll learn to do: define human development and identify the stages of human development

Graphic of stages of human growth from infancy to adulthood

What aspects of ourselves change and develop as we journey through life? We move through significant physical, cognitive, and psychosocial changes throughout our lives—do these changes happen in a systematic way, and to everyone? How much is due to genetics and how much is due to environmental influences and experiences (both within our personal control and beyond)? Is there just one course of development or are there many different courses of development? In this module, we’ll examine these questions and learn about the major stages of development and what kind of developmental tasks and transitions we might expect along the way.

Learning Outcomes

Describe human development and its three domains: physical, cognitive, and psychosocial development
Explain key human development issues about the nature of change: continuous/discontinuous, one course/multiple courses, and nature/nurture
Describe the basic periods of human development

Defining Human Development

Human development refers to the physical, cognitive, and psychosocial development of humans throughout the lifespan. What types of development are involved in each of these three domains, or areas, of life? Physical development involves growth and changes in the body and brain, the senses, motor skills, and health and wellness. Cognitive development involves learning, attention, memory, language, thinking, reasoning, and creativity. Psychosocial development involves emotions, personality, and social relationships.

Physical Domain

Many of us are familiar with the height and weight charts that pediatricians consult to estimate if babies, children, and teens are growing within normative ranges of physical development. We may also be aware of changes in children’s fine and gross motor skills, as well as their increasing coordination, particularly in terms of playing sports. But we may not realize that physical development also involves brain development, which not only enables childhood motor coordination but also greater coordination between emotions and planning in adulthood, as our brains are not done developing in infancy or childhood. Physical development also includes puberty, sexual health, fertility, menopause, changes in our senses, and primary versus secondary aging. Healthy habits with nutrition and exercise are also important at every age and stage across the lifespan.

Cognitive Domain

If we watch and listen to infants and toddlers, we can’t help but wonder how they learn so much so fast, particularly when it comes to language development. Then as we compare young children to those in middle childhood, there appear to be huge differences in their ability to think logically about the concrete world around them. Cognitive development includes mental processes, thinking, learning, and understanding, and it doesn’t stop in childhood. Adolescents develop the ability to think logically about the abstract world (and may like to debate matters with adults as they exercise their new cognitive skills!). Moral reasoning develops further, as does practical intelligence—wisdom may develop with experience over time. Memory abilities and different forms of intelligence tend to change with age. Brain development and the brain’s ability to change and compensate for losses is significant to cognitive functions across the lifespan, too.

Psychosocial Domain

Development in this domain involves what’s going on both psychologically and socially. Early on, the focus is on infants and caregivers, as temperament and attachment are significant. As the social world expands and the child grows psychologically, different types of play, and interactions with other children and teachers become important. Psychosocial development involves emotions, personality, self-esteem, and relationships. Peers become more important for adolescents, who are exploring new roles and forming their own identities. Dating, romance, cohabitation, marriage, having children, and finding work or a career are all parts of the transition into adulthood. Psychosocial development continues across adulthood with similar (and some different) developmental issues of family, friends, parenting, romance, divorce, remarriage, blended families, caregiving for elders, becoming grandparents and great grandparents, retirement, new careers, coping with losses, and death and dying.

As you may have already noticed, physical, cognitive, and psychosocial development are often interrelated, as with the example of brain development. We will be examining human development in these three domains in detail throughout the modules in this course, as we learn about infancy/toddlerhood, early childhood, middle childhood, adolescence, young adulthood, middle adulthood, and late adulthood development, as well as death and dying.

Who Studies Human Development and Why?

Many academic disciplines contribute to the study of development and this type is offered in some schools as psychology (particularly as developmental psychology); in other schools, it is taught under sociology, human development, or family studies. This multidisciplinary course is made up of contributions from researchers in the areas of health care, anthropology, nutrition, child development, biology, gerontology, psychology, and sociology, among others. Consequently, the stories provided are rich and well-rounded and the theories and findings can be part of a collaborative effort to understand human lives.

The main goals of those involved in studying human development are to describe and explain changes. Throughout this course, we will describe observations during development, then examine how theories provide explanations for why these changes occur. For example, you may observe two-year-old children be particularly temperamental, and researchers offer theories to explain why that is. We’ll learn a lot more about theories, especially developmental theories, in the next module.

What you’ll learn to do: describe the theories of lifespan development

Graphic of a brain filled with emojis and random objects

Learning outcomes

Describe theories as they relate to lifespan development
Explain Bronfenbrenner’s bioecological model
Contrast the main psychological theories that apply to human development

Understanding Theories

In l ifespan development, we need to rely on a systematic approach to understanding behavior, based on observable events and the scientific method. There are so many different observations about childhood, adulthood, and development in general that we use theories to help organize all of the different observable events or variables. A theory is a simplified explanation of the world that attempts to explain how variables interact with each other. It can take complex, interconnected issues and narrow them down to the essentials. This enables developmental theorists and researchers to analyze the problem in greater depth.

flowchart showing that a theory is used to form a hypothesis, the hypothesis leads to research, research leads to observation, which leads to the creation or modification of a theory, then back around.

Two key concepts in the scientific approach are theory and hypothesis. A theory is a well-developed set of ideas that propose an explanation for observed phenomena that can be used to make predictions about future observations. A hypothesis is a testable prediction that is arrived at logically from a theory. It is often worded as an if-then statement (e.g., if I study all night, I will get a passing grade on the test). The hypothesis is extremely important because it bridges the gap between the realm of ideas and the real world. As specific hypotheses are tested, theories are modified and refined to reflect and incorporate the result of these tests. In essence, lifespan theories explain observable events in a meaningful way. They are not as specific as hypotheses, which are so specific that we use them to make predictions in research. Theories offer more general explanations about behavior and events.

Think of theories are guidelines much like directions that come with an appliance or other object that required assembly. The instructions can help one piece together smaller parts more easily than if trial and error are used.

Theories can be developed using induction, in which a number of single cases are observed and after patterns or similarities are noted, the theorist develops ideas based on these examples. Established theories are then tested through research; however, not all theories are equally suited to scientific investigation. Some theories are difficult to test but are still useful in stimulating debate or providing concepts that have practical application. Keep in mind that theories are not facts; they are guidelines for investigation and practice, and they gain credibility through research that fails to disprove them.

People who study lifespan development approach it from different perspectives. Each perspective encompasses one or more theories—the broad, organized explanations and predictions concerning phenomena of interest. Theories of development provide a framework for thinking about human growth, development, and learning. If you have ever wondered about what motivates human thought and behavior, understanding these theories can provide useful insight into individuals and society.

Throughout psychological history and still in the present day, three key issues remain among which developmental theorists often disagree. Particularly oft-disputed is the role of early experiences on later development in opposition to current behavior reflecting present experiences–namely the passive versus active issue . Likewise, whether or not development is best viewed as occurring in stages or rather as a gradual and cumulative process of change has traditionally been up for debate – a question of continuity versus discontinuity. Further, the role of heredity and the environment in shaping human development is a much-contested topic of discussion – also referred to as the nature/nurture debate .

Is Development Continuous or Discontinuous?

Continuous development views development as a cumulative process, gradually improving on existing skills (Figure 2). With this type of development, there is a gradual change. Consider, for example, a child’s physical growth: adding inches to their height year by year. In contrast, theorists who view development as discontinuous believe that development takes place in unique stages and that it occurs at specific times or ages. With this type of development, the change is more sudden, such as an infant’s ability to demonstrate awareness of object permanence (which is a cognitive skill that develops toward the end of infancy, according to Piaget’s cognitive theory—more on that theory in the next module).

Is There One Course of Development or Many?

Stage theories hold that the sequence of development is universal. For example, in cross-cultural studies of language development, children from around the world reach language milestones in a similar sequence (Gleitman & Newport, 1995). Infants in all cultures coo before they babble. They begin babbling at about the same age and utter their first word around 12 months old. Yet we live in diverse contexts that have a unique effect on each of us. For example, researchers once believed that motor development followed one course for all children regardless of culture. However, childcare practices vary by culture, and different practices have been found to accelerate or inhibit the achievement of developmental milestones such as sitting, crawling, and walking (Karasik, Adolph, Tamis-LeMonda, & Bornstein, 2010).

For instance, let’s look at the Aché society in Paraguay. They spend a significant amount of time foraging in forests. While foraging, Aché mothers carry their young children, rarely putting them down in order to protect them from getting hurt in the forest. Consequently, their children walk much later: They walk around 23–25 months old, in comparison to infants in Western cultures who begin to walk around 12 months old. However, as Aché children become older, they are allowed more freedom to move about, and by about age 9, their motor skills surpass those of U.S. children of the same age: Aché children are able to climb trees up to 25 feet tall and use machetes to chop their way through the forest (Kaplan & Dove, 1987). As you can see, our development is influenced by multiple contexts, so the timing of basic motor functions may vary across cultures. However, the functions are present in all societies.

How Do Nature and Nurture Influence Development?

Are we who we are because of nature (biology and genetics), or are we who we are because of nurture (our environment and culture)? This longstanding question is known in psychology as the nature versus nurture debate. It seeks to understand how our personalities and traits are the product of our genetic makeup and biological factors, and how they are shaped by our environment, including our parents, peers, and culture. For instance, why do biological children sometimes act like their parents—is it because of genetics or because of early childhood environment and what the child has learned from their parents? What about children who are adopted—are they more like their biological families or more like their adoptive families? And how can siblings from the same family be so different?

We are all born with specific genetic traits inherited from our parents, such as eye color, height, and certain personality traits. Beyond our basic genotype, however, there is a deep interaction between our genes and our environment. Our unique experiences in our environment influence whether and how particular traits are expressed, and at the same time, our genes influence how we interact with our environment (Diamond, 2009; Lobo, 2008). There is a reciprocal interaction between nature and nurture as they both shape who we become, but the debate continues as to the relative contributions of each.

History of Developmental Psychology

Photograph of early psychologists, including Freud and Hall.

The scientific study of children began in the late nineteenth century and blossomed in the early twentieth century as pioneering psychologists sought to uncover the secrets of human behavior by studying its development.

Early scholars John Locke and Charles Darwin proposed theories of human behavior that are the “direct ancestors of some major theoretical traditions” of developmental psychology today(Vasta et al., 1998, p. 10). Locke, a British empiricist, adhered to a strict environmentalist position. He saw the newborn’s mind as a tabula rasa (“blank slate”) on which knowledge is written through experience and learning. Finally, the work of Darwin, the British biologist famous for his theory of evolution, led others to suggest that development proceeds through evolutionary recapitulation, with many human behaviors having their origins in successful adaptations in the past.

John B. Watson

The 20th century marked the formation of qualitative distinctions between children and adults. When John Watson wrote the book Psychological Care of Infant and Child in 1928, he sought to add clarification surrounding behaviorists’ views on child care and development. Watson was the founder of the field of behaviorism, which emphasized the role of nurture, or the environment, in human development. He believed, based on Locke’s environmentalist position, that human behavior can be understood in terms of experiences and learning. He believed that all behaviors are learned, or conditioned, as evidenced by his famous “Little Albert” study, in which he conditioned an infant to fear a white rat. In Watson’s book on the care of the infant and child, Watson explained that children should be treated as a young adult—with respect, but also without emotional attachment. In the book, he warned against the inevitable dangers of a mother providing too much love and affection. Watson explained that love, along with everything else as the behaviorist saw the world, is conditioned. Watson supported his warnings by mentioning invalidism, saying that society does not overly comfort children as they become young adults in the real world, so parents should not set up these unrealistic expectations. His book became highly criticized but was still influential in promoting more research into early childhood behavior and development.

Sigmund Freud

Another name you are probably familiar with who was influential in the study of human development is Sigmund Freud. Sigmund Freud’s model of “psychosexual development” grew out of his psychoanalytic approach to human personality and psychopathology. In sharp contrast to the objective approach espoused by Watson, Freud based his model of child development on his own and his patients’ recollections of their childhood. He developed a stage model of development in which the libido, or sexual energy, of the child, focuses on different “zones” or areas of the body as the child grows to adulthood. Freud’s model is an “interactionist” one since he believed that although the sequence and timing of these stages are biologically determined, successful personality development depends on the experiences the child has during each stage. Although the details of Freud’s developmental theory have been widely criticized, his emphasis on the importance of early childhood experiences, prior to five years of age, has had a lasting impact.

Freud emphasized the importance of early childhood experiences in shaping our personality and behavior. In our natural state, we are biological beings. We are driven primarily by instincts. During childhood, however, we begin to become social beings as we learn how to manage our instincts and transform them into socially acceptable behaviors. The type of parenting the child receives has a very powerful impact on the child’s personality development. We will explore this idea further in our discussion of psychosexual development, but first, we must identify the parts of the “self” in Freud’s model, or in other words, what constitutes a person’s personality and makes us who we are.

Jean Piaget

Jean Piaget (1896-1980) is considered one of the most influential psychologists of the twentieth century, and his stage theory of cognitive development revolutionized our view of children’s thinking and learning. His work inspired more research than any other theorist, and many of his concepts are still foundational to developmental psychology. His interest lay in children’s knowledge, their thinking, and the qualitative differences in their thinking as it develops. Although he called his field “genetic epistemology,” stressing the role of biological determinism, he also assigned great importance to experience. In his view, children “construct” their knowledge through processes of “assimilation,” in which they evaluate and try to understand new information, based on their existing knowledge of the world, and “accommodation,” in which they expand and modify their cognitive structures based on new experiences.

Modern developmental psychology generally focuses on how and why certain modifications throughout an individual’s life-cycle (cognitive, social, intellectual, personality) and human growth change over time. There are many theorists that have made, and continue to make, a profound contribution to this area of psychology, amongst whom is Erik Erikson who developed a model of eight stages of psychological development. He believed that humans developed in stages throughout their lifetimes and this would affect their behaviors. In this module, we’ll examine some of these major theories and contributions made by prominent psychologists.

Bronfenbrenner’s Ecological Systems Theory

Another psychologist who recognized the importance of the environment on development was American psychologist, Urie Bronfenbrenner (1917-2005), who formulated the ecological systems theory to explain how the inherent qualities of a child and their environment interact to influence how they will grow and develop. The term “ecological” refers to a natural environment; human development is understood through this model as a long-lasting transformation in the way one perceives and deals with the environment. Bronfenbrenner’s ecological theory stresses the importance of studying children in the context of multiple environments because children typically find themselves enmeshed simultaneously in different ecosystems. Each of these systems inevitably interact with and influence each other in every aspect of the child’s life, from the most intimate level to the broadest. Furthermore, he eventually renamed his theory the bioecological model in order to recognize the importance of biological processes in development. However, he only recognized biology as producing a person’s potential, with this potential being realized or not via environmental and social forces.

An individual is impacted by microsystems such as parents or siblings; those who have direct, significant contact with the person. The input of those people is modified by the cognitive and biological state of the individual as well. These influence the person’s actions, which in turn influence systems operating on them. The mesosystem includes larger organizational structures such as school, the family, or religion. These institutions impact the microsystems just described. For example, the religious teachings and traditions of a family may create a climate that makes the family feel stigmatized and this indirectly impacts the child’s view of themselves and others. The philosophy of the school system, daily routine, assessment methods, and other characteristics can affect the child’s self-image, growth, sense of accomplishment, and schedule, thereby impacting the child physically, cognitively, and emotionally. These mesosystems both influence and are influenced by the larger contexts of the community, referred to as the exosystem . A community’s values, history, and economy can impact the organizational structures it houses. And the community is influenced by macrosystems , which are cultural elements such as global economic conditions, war, technological trends, values, philosophies, and a society’s responses to the global community. In sum, a child’s experiences are shaped by larger forces such as the family, school, religion, and culture. All of this occurs within the relevant historical context and timeframe, or chronosystem . The chronosystem is made up of the environmental events and transitions that occur throughout a child’s life, including any socio-historical events. This system consists of all the experiences that a person has had during their lifetime.

Image of Brofenbrenner's system, displayed as a target. In the center circle is an individual, then the microsystem, the mesosystem, the exosystem, and the macrosystem.

Comparing and Evaluating Lifespan Theories

Developmental theories provide a set of guiding principles and concepts that describe and explain human development. Some developmental theories focus on the formation of a particular quality, such as Piaget’s theory of cognitive development. Other developmental theories focus on growth that happens throughout the lifespan, such as Erikson’s theory of psychosocial development. It would be natural to wonder which of the perspectives provides the most accurate account of human development, but clearly, each perspective is based on its own premises and focuses on different aspects of development. Many lifespan developmentalists use an eclectic approach, drawing on several perspectives at the same time because the same developmental phenomenon can be looked at from a number of perspectives.

In the table below, we’ll review some of the major theories that you learned about in your introductory course and others that we will cover throughout this text. Recall that three key issues considered in human development examine if development is continuous or discontinuous, if it is the same for everyone or distinct for individuals (one course of development or many), and if development is more influenced by nature or by nurture. The table below reviews how each of these major theories approaches each of these issues.

Periods of Human Development

Think about the lifespan and make a list of what you would consider the basic periods of development. How many periods or stages are on your list? Perhaps you have three: childhood, adulthood, and old age. Or maybe four: infancy, childhood, adolescence, and adulthood. Developmentalists often break the lifespan into nine stages:

Prenatal Development
Infancy and Toddlerhood
Early Childhood
Middle Childhood
Adolescence
Emerging Adulthood
Early Adulthood
Middle Adulthood
Late Adulthood

In addition, the topic of “Death and Dying” is usually addressed after late adulthood since overall, the likelihood of dying increases in later life (though individual and group variations exist). Death and dying will be the topic of our second to last module, though it is not necessarily a stage of development that occurs at a particular age. Our last module will cover grief and bereavement.

The list of the periods of development reflects unique aspects of the various stages of childhood and adulthood that will be explored in this book, including physical, cognitive, and psychosocial changes. So while both an 8-month-old and an 8-year-old are considered children, they have very different motor abilities, cognitive skills, and social relationships. Their nutritional needs are different, and their primary psychological concerns are also distinctive. The same is true of an 18-year-old and an 80-year-old, both considered adults. We will discover the distinctions between being 28 or 48 as well. But first, here is a brief overview of the stages.

Think about your own development. Which period or stage of development are you in right now? Are you dealing with similar issues and experiencing comparable physical, cognitive, and psychosocial development as described above? If not, why not? Are important aspects of development missing and if so, are they common for most of your cohort or unique to you?

What you’ll learn to do: explain the lifespan perspective

Several people walking down a street shown from above

As we have learned, human development refers to the physical, cognitive, and psychosocial changes and constancies in humans over time. There are various theories pertaining to each domain of development, and often theorists and researchers focus their attention on specific periods of development (with most traditionally focusing on infancy and childhood; some on adolescence). But isn’t it possible that development during one period affects development in other periods and that humans can grow and change across adulthood too? In this section, we’ll learn about development through the lifespan perspective, which emphasizes the multidimensional, interconnected, and ever-changing influences on development.

Describe Baltes’ lifespan perspective with its key principles about development
Explain what is meant by development being lifelong, multidimensional, and multidirectional
Explain contextual influences on development

The Lifespan Perspective

Lifespan development involves the exploration of biological, cognitive, and psychosocial changes and constancies that occur throughout the entire course of life. It has been presented as a theoretical perspective, proposing several fundamental, theoretical, and methodological principles about the nature of human development. An attempt by researchers has been made to examine whether research on the nature of development suggests a specific metatheoretical worldview. Several beliefs, taken together, form the “family of perspectives” that contribute to this particular view.

German psychologist Paul Baltes, a leading expert on lifespan development and aging, developed one of the approaches to studying development called the lifespan perspective . This approach is based on several key principles:

Development occurs across one’s entire life or is lifelong.
Development is multidimensional, meaning it involves the dynamic interaction of factors like physical, emotional, and psychosocial development
Development is multidirectional and results in gains and losses throughout life
Development is plastic , meaning that characteristics are malleable or changeable.
Development is influenced by contextual and socio-cultural influences.
Development is multidisciplinary.

Development is lifelong

Lifelong development means that development is not completed in infancy or childhood or at any specific age; it encompasses the entire lifespan, from conception to death. The study of development traditionally focused almost exclusively on the changes occurring from conception to adolescence and the gradual decline in old age; it was believed that the five or six decades after adolescence yielded little to no developmental change at all. The current view reflects the possibility that specific changes in development can occur later in life, without having been established at birth. The early events of one’s childhood can be transformed by later events in one’s life. This belief clearly emphasizes that all stages of the lifespan contribute to the regulation of the nature of human development.

Many diverse patterns of change, such as direction, timing, and order, can vary among individuals and affect the ways in which they develop. For example, the developmental timing of events can affect individuals in different ways because of their current level of maturity and understanding. As individuals move through life, they are faced with many challenges, opportunities, and situations that impact their development. Remembering that development is a lifelong process helps us gain a wider perspective on the meaning and impact of each event.

Development is multidimensional

By multidimensionality, Baltes is referring to the fact that a complex interplay of factors influence development across the lifespan, including biological, cognitive, and socioemotional changes. Baltes argues that a dynamic interaction of these factors is what influences an individual’s development.

For example, in adolescence, puberty consists of physiological and physical changes with changes in hormone levels, the development of primary and secondary sex characteristics, alterations in height and weight, and several other bodily changes. But these are not the only types of changes taking place; there are also cognitive changes, including the development of advanced cognitive faculties such as the ability to think abstractly. There are also emotional and social changes involving regulating emotions, interacting with peers, and possibly dating. The fact that the term puberty encompasses such a broad range of domains illustrates the multidimensionality component of development (think back to the physical, cognitive, and psychosocial domains of human development we discussed earlier in this module).

Development is multidirectional

Baltes states that the development of a particular domain does not occur in a strictly linear fashion but that the development of certain traits can be characterized as having the capacity for both an increase and decrease in efficacy over the course of an individual’s life.

If we use the example of puberty again, we can see that certain domains may improve or decline in effectiveness during this time. For example, self-regulation is one domain of puberty that undergoes profound multidirectional changes during the adolescent period. During childhood, individuals have difficulty effectively regulating their actions and impulsive behaviors. Scholars have noted that this lack of effective regulation often results in children engaging in behaviors without fully considering the consequences of their actions. Over the course of puberty, neuronal changes modify this unregulated behavior by increasing the ability to regulate emotions and impulses. Inversely, the ability for adolescents to engage in spontaneous activity and creativity, both domains commonly associated with impulse behavior, decrease over the adolescent period in response to changes in cognition. Neuronal changes to the limbic system and prefrontal cortex of the brain, which begin in puberty lead to the development of self-regulation, and the ability to consider the consequences of one’s actions (though recent brain research reveals that this connection will continue to develop into early adulthood).

Extending on the premise of multidirectionality, Baltes also argued that development is influenced by the “joint expression of features of growth (gain) and decline (loss)”. This relation between developmental gains and losses occurs in a direction to selectively optimize particular capacities. This requires the sacrificing of other functions, a process known as selective optimization with compensation. According to the process of selective optimization, individuals prioritize particular functions above others, reducing the adaptive capacity of particulars for specialization and improved efficacy of other modalities.

The acquisition of effective self-regulation in adolescents illustrates this gain/loss concept. As adolescents gain the ability to effectively regulate their actions, they may be forced to sacrifice other features to selectively optimize their reactions. For example, individuals may sacrifice their capacity to be spontaneous or creative if they are constantly required to make thoughtful decisions and regulate their emotions. Adolescents may also be forced to sacrifice their fast reaction times toward processing stimuli in favor of being able to fully consider the consequences of their actions.

Development is plastic

Plasticity denotes intrapersonal variability and focuses heavily on the potentials and limits of the nature of human development. The notion of plasticity emphasizes that there are many possible developmental outcomes and that the nature of human development is much more open and pluralistic than originally implied by traditional views; there is no single pathway that must be taken in an individual’s development across the lifespan. Plasticity is imperative to current research because the potential for intervention is derived from the notion of plasticity in development. Undesired development or behaviors could potentially be prevented or changed.

As an example, recently researchers have been analyzing how other senses compensate for the loss of vision in blind individuals. Without visual input, blind humans have demonstrated that tactile and auditory functions still fully develop and they can use tactile and auditory cues to perceive the world around them. One experiment designed by Röder and colleagues (1999) compared the auditory localization skills of people who are blind with people who are sighted by having participants locate sounds presented either centrally or peripherally (lateral) to them. Both congenitally blind adults and sighted adults could locate a sound presented in front of them with precision but people who are blind were clearly superior in locating sounds presented laterally. Currently, brain-imaging studies have revealed that the sensory cortices in the brain are reorganized after visual deprivation. These findings suggest that when vision is absent in development, the auditory cortices in the brain recruit areas that are normally devoted to vision, thus becoming further refined.

A significant aspect of the aging process is cognitive decline. The dimensions of cognitive decline are partially reversible, however, because the brain retains the lifelong capacity for plasticity and reorganization of cortical tissue. Mahncke and colleagues developed a brain plasticity-based training program that induced learning in mature adults experiencing an age-related decline. This training program focused intensively on aural language reception accuracy and cognitively demanding exercises that have been proven to partially reverse the age-related losses in memory. It included highly rewarding novel tasks that required attention control and became progressively more difficult to perform. In comparison to the control group, who received no training and showed no significant change in memory function, the experimental training group displayed a marked enhancement in memory that was sustained at the 3-month follow-up period. These findings suggest that cognitive function, particularly memory, can be significantly improved in mature adults with age-related cognitive decline by using brain plasticity-based training methods.

Development is contextual

In Baltes’ theory, the paradigm of contextualism refers to the idea that three systems of biological and environmental influences work together to influence development. Development occurs in context and varies from person to person, depending on factors such as a person’s biology, family, school, church, profession, nationality, and ethnicity. Baltes identified three types of influences that operate throughout the life course: normative age-graded influences, normative history-graded influences, and nonnormative influences. Baltes wrote that these three influences operate throughout the life course, their effects accumulate with time, and, as a dynamic package, they are responsible for how lives develop.

Normative age-graded influences are those biological and environmental factors that have a strong correlation with chronological age, such as puberty or menopause, or age-based social practices such as beginning school or entering retirement. Normative history-graded influences are associated with a specific time period that defines the broader environmental and cultural context in which an individual develops. For example, development and identity are influenced by historical events of the people who experience them, such as the Great Depression, WWII, Vietnam, the Cold War, the War on Terror, or advances in technology.

This has been exemplified in numerous studies, including Nesselroade and Baltes’, showing that the level and direction of change in adolescent personality development was influenced as strongly by the socio-cultural settings at the time (in this case, the Vietnam War) as age-related factors. The study involved individuals of four different adolescent age groups who all showed significant personality development in the same direction (a tendency to occupy themselves with ethical, moral, and political issues rather than cognitive achievement). Similarly, Elder showed that the Great Depression was a setting that significantly affected the development of adolescents and their corresponding adult personalities, by showing a similar common personality development across age groups. Baltes’ theory also states that the historical socio-cultural setting had an effect on the development of an individual’s intelligence. The areas of influence that Baltes thought most important to the development of intelligence were health, education, and work. The first two areas, health and education, significantly affect adolescent development because healthy children who are educated effectively will tend to develop a higher level of intelligence. The environmental factors, health and education, have been suggested by Neiss and Rowe to have as much effect on intelligence as inherited intelligence.

Nonnormative influences are unpredictable and not tied to a certain developmental time in a person’s development or to a historical period. They are the unique experiences of an individual, whether biological or environmental, that shape the development process. These could include milestones like earning a master’s degree or getting a certain job offer or other events like going through a divorce or coping with the death of a child.

The most important aspect of contextualism as a paradigm is that the three systems of influence work together to affect development. Concerning adolescent development, the age-graded influences would help to explain the similarities within a cohort, the history-graded influences would help to explain the differences between cohorts, and the nonnormative influences would explain the idiosyncrasies of each adolescent’s individual development. When all influences are considered together, it provides a broader explanation of an adolescent’s development.

Other Contextual Influences on Development: Cohort, Socioeconomic Status, and Culture

What is meant by the word “context”? It means that we are influenced by when and where we live. Our actions, beliefs, and values are a response to the circumstances surrounding us. Sternberg describes contextual intelligence as the ability to understand what is called for in a situation (Sternberg, 1996). The key here is to understand that behaviors, motivations, emotions, and choices are all part of a bigger picture. Our concerns are such because of who we are socially, where we live, and when we live; they are part of a social climate and set of realities that surround us. Important social factors include cohort, social class, gender, race, ethnicity, and age. Let’s begin by exploring two of these: cohort and social class.

A cohort is a group of people who are born at roughly the same time period in a particular society. Cohorts share histories and contexts for living. Members of a cohort have experienced the same historical events and cultural climates which have an impact on the values, priorities, and goals that may guide their lives.

Another context that influences our lives is our social standing, socioeconomic status, or social class. Socioeconomic status is a way to identify families and households based on their shared levels of education, income, and occupation. While there is certainly individual variation, members of a social class tend to share similar lifestyles, patterns of consumption, parenting styles, stressors, religious preferences, and other aspects of daily life.

Culture is often referred to as a blueprint or guideline shared by a group of people that specifies how to live. It includes ideas about what is right and wrong, what to strive for, what to eat, how to speak, what is valued, as well as what kinds of emotions are called for in certain situations. Culture teaches us how to live in a society and allows us to advance because each new generation can benefit from the solutions found and passed down from previous generations.

Culture is learned from parents, schools, churches, media, friends, and others throughout a lifetime. The kinds of traditions and values that evolve in a particular culture serve to help members function in their own society and to value their own society. We tend to believe that our own culture’s practices and expectations are the right ones. This belief that our own culture is superior is called ethnocentrism and is a normal by-product of growing up in a culture. It becomes a roadblock, however, when it inhibits understanding of cultural practices from other societies. Cultural relativity is an appreciation for cultural differences and the understanding that cultural practices are best understood from the standpoint of that particular culture.

Culture is an extremely important context for human development and understanding development requires being able to identify which features of development are culturally based. This understanding is somewhat new and still being explored. So much of what developmental theorists have described in the past has been culturally bound and difficult to apply to various cultural contexts. For example, Erikson’s theory that teenagers struggle with identity assumes that all teenagers live in a society in which they have many options and must make an individual choice about their future. In many parts of the world, one’s identity is determined by family status or society’s dictates. In other words, there is no choice to make.

Even the most biological events can be viewed in cultural contexts that are extremely varied. Consider two very different cultural responses to menstruation in young girls. In the United States, girls in public school often receive information on menstruation around 5th grade, get a kit containing feminine hygiene products, and receive some sort of education about sexual health. Contrast this with some developing countries where menstruation is not publicly addressed, or where girls on their period are forced to miss school due to limited access to feminine products or unjust attitudes about menstruation.

Development is Multidisciplinary

Any single discipline’s account of development across the lifespan would not be able to express all aspects of this theoretical framework. That is why it is suggested explicitly by lifespan researchers that a combination of disciplines is necessary to understand development. Psychologists, sociologists, neuroscientists, anthropologists, educators, economists, historians, medical researchers, and others may all be interested and involved in research related to the normative age-graded, normative history-graded, and nonnormative influences that help shape development. Many disciplines are able to contribute important concepts that integrate knowledge, which may ultimately result in the formation of a new and enriched understanding of development across the lifespan.

Consider your cohort. Can you identify it? Does it have a name and if so, what does the name imply? To what extent does your cohort shape your values, thoughts, and aspirations? (Some cohort labels popularized in the media for generations in the United States include Baby Boomers, Generation X, Millennials, and Generation Z.)
Think of other ways culture may have affected your development. How might cultural differences influence interactions between teachers and students, nurses and patients, or other relationships?

Additional Supplemental Resources

Want to participate in a study? Click on a link that sounds interesting to you in order to participate in online research
U.S. Census Data is available and widely used to look at trends and changes taking place in the United States
KFF is an endowed, nonprofit organization filling the need for trusted, independent information on national health issues.
SRCD launched a project to increase the visibility of leading developmental scientists of color who have made critical research contributions and paved the way, through mentoring and advocacy, for younger scholars of color.
This video gives a summary of Piaget’s theory and his four stages of cognitive development.
This video summarizes Erikson’s theory of psychosocial development which identifies eight stages in which a healthy individual should pass through from birth to death.
This video on research methods covers the different categories of psychological research including observational studies and experiments. Closed captioning available.

How to Age Gracefully

People of all ages offer words of wisdom to their younger counterparts in this WireTap video, from CBC Radio One. It is a great overview of the journey we will take through the lifespan.

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Stephanie M. Wright - Georgia Gwinnett College Psychology Department
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Case Studies in Lifespan Development offers students a comprehensive view into life’s key developmental stages through unique, diverse, and moving cases. Author Stephanie M. Wright presents a series of 12 case studies shaped by the contributions of real students—including their observations, concerns, and moments of triumph—to build immersive examples that readers can relate to and enjoy. INSTRUCTORS: Bundle Case Studies in Lifespan Development with one of the best-selling core texts below for only $5 more! SAGE coursepacks LMS resources accompanying these texts allow you to track student understanding of the entire human lifespan with auto-graded assessments and open-ended discussion questions.

Lifespan Development: Lives in Context, Second Edition : Chronologically organized, this book explores the dynamic interactions between individuals, our genetic makeup, and the diverse contexts that shape our growth and development at every stage of life.
Lifespan Development in Context: A Topical Approach: Provides a panoramic view of the many influences that shape human development.
Child Development From Infancy to Adolescence: An Active Learning Approach, Second Edition : Chronologically organized, this book presents topics within the field of child development through unique and highly engaging Active Learning opportunities.

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50 What Is Lifespan Development?

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Learning Objectives

By the end of this section, you will be able to:

Define and distinguish between the three domains of development: physical, cognitive and psychosocial
Discuss the normative approach to development
Understand the three major issues in development: continuity and discontinuity, one common course of development or many unique courses of development, and nature versus nurture

My heart leaps up when I behold A rainbow in the sky: So was it when my life began; So is it now I am a man; So be it when I shall grow old, Or let me die! The Child is father of the Man; I could wish my days to be Bound each to each by natural piety. (Wordsworth, 1802)

Across these three domains—physical, cognitive, and psychosocial—the normative approach to development is also discussed. This approach asks, “What is normal development?” In the early decades of the 20th century, normative psychologists studied large numbers of children at various ages to determine norms (i.e., average ages) of when most children reach specific developmental milestones in each of the three domains (Gesell, 1933, 1939, 1940; Gesell & Ilg, 1946; Hall, 1904). Although children develop at slightly different rates, we can use these age-related averages as general guidelines to compare children with same-age peers to determine the approximate ages they should reach specific normative events called developmental milestones (e.g., crawling, walking, writing, dressing, naming colors, speaking in sentences, and starting puberty).

Not all normative events are universal, meaning they are not experienced by all individuals across all cultures. Biological milestones, such as puberty, tend to be universal, but social milestones, such as the age when children begin formal schooling, are not necessarily universal; instead, they affect most individuals in a particular culture (Gesell & Ilg, 1946). For example, in developed countries children begin school around 5 or 6 years old, but in developing countries, like Nigeria, children often enter school at an advanced age, if at all (Huebler, 2005; United Nations Educational, Scientific, and Cultural Organization [UNESCO], 2013).

The Centers for Disease Control and Prevention (CDC) describes the developmental milestones for children from 2 months through 5 years old. After reviewing the information, take this quiz to see how well you recall what you’ve learned. If you are a parent with concerns about your child’s development, contact your pediatrician.

ISSUES IN DEVELOPMENTAL PSYCHOLOGY

Is Development Continuous or Discontinuous?

Continuous development views development as a cumulative process, gradually improving on existing skills ( [link] ). With this type of development, there is gradual change. Consider, for example, a child’s physical growth: adding inches to her height year by year. In contrast, theorists who view development as discontinuous believe that development takes place in unique stages: It occurs at specific times or ages. With this type of development, the change is more sudden, such as an infant’s ability to conceive object permanence.

Is There One Course of Development or Many?

For instance, let’s look at the Aché society in Paraguay. They spend a significant amount of time foraging in forests. While foraging, Aché mothers carry their young children, rarely putting them down in order to protect them from getting hurt in the forest. Consequently, their children walk much later: They walk around 23–25 months old, in comparison to infants in Western cultures who begin to walk around 12 months old. However, as Aché children become older, they are allowed more freedom to move about, and by about age 9, their motor skills surpass those of U.S. children of the same age: Aché children are able to climb trees up to 25 feet tall and use machetes to chop their way through the forest (Kaplan & Dove, 1987). As you can see, our development is influenced by multiple contexts, so the timing of basic motor functions may vary across cultures. However, the functions themselves are present in all societies ( [link] ).

How Do Nature and Nurture Influence Development?

Are we who we are because of nature (biology and genetics), or are we who we are because of nurture (our environment and culture)? This longstanding question is known in psychology as the nature versus nurture debate. It seeks to understand how our personalities and traits are the product of our genetic makeup and biological factors, and how they are shaped by our environment, including our parents, peers, and culture. For instance, why do biological children sometimes act like their parents—is it because of genetics or because of early childhood environment and what the child has learned from the parents? What about children who are adopted—are they more like their biological families or more like their adoptive families? And how can siblings from the same family be so different?

We are all born with specific genetic traits inherited from our parents, such as eye color, height, and certain personality traits. Beyond our basic genotype, however, there is a deep interaction between our genes and our environment: Our unique experiences in our environment influence whether and how particular traits are expressed, and at the same time, our genes influence how we interact with our environment (Diamond, 2009; Lobo, 2008). This chapter will show that there is a reciprocal interaction between nature and nurture as they both shape who we become, but the debate continues as to the relative contributions of each.

The achievement gap refers to the persistent difference in grades, test scores, and graduation rates that exist among students of different ethnicities, races, and—in certain subjects—sexes (Winerman, 2011). Research suggests that these achievement gaps are strongly influenced by differences in socioeconomic factors that exist among the families of these children. While the researchers acknowledge that programs aimed at reducing such socioeconomic discrepancies would likely aid in equalizing the aptitude and performance of children from different backgrounds, they recognize that such large-scale interventions would be difficult to achieve. Therefore, it is recommended that programs aimed at fostering aptitude and achievement among disadvantaged children may be the best option for dealing with issues related to academic achievement gaps (Duncan & Magnuson, 2005).

Psychologists Betty Hart and Todd Risley (2006) spent their careers looking at early language ability and progression of children in various income levels. In one longitudinal study, they found that although all the parents in the study engaged and interacted with their children, middle- and high-income parents interacted with their children differently than low-income parents. After analyzing 1,300 hours of parent-child interactions, the researchers found that middle- and high-income parents talk to their children significantly more, starting when the children are infants. By 3 years old, high-income children knew almost double the number of words known by their low-income counterparts, and they had heard an estimated total of 30 million more words than the low-income counterparts (Hart & Risley, 2003). And the gaps only become more pronounced. Before entering kindergarten, high-income children score 60% higher on achievement tests than their low-income peers (Lee & Burkam, 2002).

There are solutions to this problem. At the University of Chicago, experts are working with low-income families, visiting them at their homes, and encouraging them to speak more to their children on a daily and hourly basis. Other experts are designing preschools in which students from diverse economic backgrounds are placed in the same classroom. In this research, low-income children made significant gains in their language development, likely as a result of attending the specialized preschool (Schechter & Byeb, 2007). What other methods or interventions could be used to decrease the achievement gap? What types of activities could be implemented to help the children of your community or a neighboring community?

Lifespan development explores how we change and grow from conception to death. This field of psychology is studied by developmental psychologists. They view development as a lifelong process that can be studied scientifically across three developmental domains: physical, cognitive development, and psychosocial. There are several theories of development that focus on the following issues: whether development is continuous or discontinuous, whether development follows one course or many, and the relative influence of nature versus nurture on development.

Review Questions

The view that development is a cumulative process, gradually adding to the same type of skills is known as ________.

continuous development
discontinuous development

Developmental psychologists study human growth and development across three domains. Which of the following is not one of these domains?

psychological
psychosocial

How is lifespan development defined?

The study of how we grow and change from conception to death.
The study of how we grow and change in infancy and childhood.
The study of physical, cognitive, and psychosocial growth in children.
The study of emotions, personality, and social relationships.

Critical Thinking Questions

Describe the nature versus nurture controversy, and give an example of a trait and how it might be influenced by each?

The nature versus nurture controversy seeks to understand whether our personalities and traits are the product of our genetic makeup and biological factors, or whether they are shaped by our environment, which includes such things as our parents, peers, and culture. Today, psychologists agree that both nature and nurture interact to shape who we become, but the debate over the relative contributions of each continues. An example would be a child learning to walk: Nature influences when the physical ability occurs, but culture can influence when a child masters this skill, as in Aché culture.

Compare and contrast continuous and discontinuous development.

Continuous development sees our development as a cumulative process: Changes are gradual. On the other hand, discontinuous development sees our development as taking place in specific steps or stages: Changes are sudden.

Why should developmental milestones only be used as a general guideline for normal child development?

Children develop at different rates. For example, some children may walk and talk as early as 8 months old, while others may not do so until well after their first birthday. Each child’s unique contexts will influence when he reaches these milestones.

Personal Application Questions

How are you different today from the person you were at 6 years old? What about at 16 years old? How are you the same as the person you were at those ages?

Your 3-year-old daughter is not yet potty trained. Based on what you know about the normative approach, should you be concerned? Why or why not?

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3.8: Lecture: Introduction to Life Span, Growth and Development

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Lecture Transcript

Welcome to life span, growth and development. This is the study of how and why people change or remain the same over time.

Although this course is offered in psychology, this is a very interdisciplinary course. Psychologists, nutritionists, sociologists, anthropologists, educators, and health care professionals all contribute to our knowledge of life span. We will look at how we change physically over time from early development through aging and death. We examine cognitive change-or how our ability to think and remember changes over time. We look at how our concerns and psychological state is influenced by age and finally, how our social relationships change throughout life.

There are several goals of those involved in this discipline:

Describe change -many of the studies we will examine simply involve the first step in investigation, which is description. Arnold Gesell’s study on infant motor skills, for example. 2. Explaining changes is another goal. Theories provide explanations for why we change over time. For example, Erikson offers an explanation about why our two-year-old is temperamental. Levinson offers an explanation about why a 45 year old husband is so concerned with buying a sports car. Freud offers an explanation of why films with sex and violence are such moneymakers. 3. Predict -science offers us the ability to make predictions about what the future holds. In some areas, we can make predictions about the future. For example, we know some about how smoking and drinking can affect prenatal development. 4. Influence change -ultimately, practitioners want to help people lead better, healthier and happier lives.

What is a context ? You may think of it as the background or setting in which a person exists. Our lives are impacted by a variety of contexts. We may have different world views depending on life circumstances. For example, people who grew up during the Great Depression of the 1930s in the U. S. suffered economically and sometimes carried that idea of thrift with them throughout their lives.

When and where we live creates this context. Some examples of contexts include cohort, social class, and culture. A cohort is a group of people born within the same generation in a geographic location. A social class is a category of people who share similar levels of education, income, occupational status, and consumption patterns. Culture refers to a way of life of a group of people. Through culture, we learn what to strive for, what to eat, what to think, how to behave, and so many other things. An interesting story in the news last week was an interview of an Asian student who is studying children’s interpretations of art and how this is influenced by culture. In middle class America, children are taught to look at detail and function. “This is a sturdy car that rides fast.” But in Asia, children are taught to think more abstractly about images. The ways in which our own culture affects us is often hard to see.

We grow used to our own views and ways of doing things and assume that our ways are best. Ethnocentrism is the belief in the superiority of one’s own culture and is a natural outcome from being raised in a particular culture. However, it can get in the way of understanding other cultural beliefs and practices. Cultural relativity is the ability to appreciate how another culture’s practices may be best within that culture rather than judging a practice from one’s own viewpoint.

Let me tell you a story to illustrate these concepts. Once upon a time, a long time ago, there were two creatures: a monkey and a fish. Along came a great flood. The monkey, being strong and agile, quickly climbed to the top of a tree to escape the raging waters. He looked down from his safe place and saw his friend the fish, struggling in the water. With the very best of intentions, the monkey climbed down from the tree and pulled the fish out of the water. The result was inevitable. The message is this: understanding and ultimately being able to help others requires that we also understand the contexts for development and take these into consideration when making decisions or judgments. This is particularly important if we are in a role of delivering care.

All cultures have some system of stratification. This means that categories of people are ranked in a hierarchy within society and that more wealth, status, and privilege are found when moving up. Systems can be based on social class as is the case in the United States. One profile of social class is presented in this slide. A more thorough description of each class is provided in your reading. The upper class is the smallest category and represents the highest amounts of wealth and power. The upper middle class is larger and consists of more highly paid professionals who have higher levels of education, status, and wealth. The middle class is larger still and is comprised of people who hold professional jobs that pay less and have less status. The working class is also a large category consisting of people who are more likely to hold jobs in vocational skills or trade occupations. The working poor have seasonal, inconsistent, and low-paying occupations and all of the difficulties associated with financial insecurity. The underclass is the most impoverished and the least powerful group.

With which social classes are you most likely to be involved? With whom would you feel most comfortable? Why? How might you become more effective when working with someone of a social class that differs from your own? What kinds of difficulties would people of a certain social class experience and how would these impact education, health care, nutrition, and stress levels?

Many early theories of human development were created and popularized in the early 1900s. These are referred to as stage theories because they present development as occurring in stages. The assumption is that once one stage is completed, a person moves into the next stage and that stages tend to occur only once. Some examples of stage theories that we will be studying include Freud’s psychosexual stages, Erikson’s psychosocial stages, and Piaget’s stages of cognitive development, to name a few.

These theories are appealing in a way because they provide the ability to predict what will happen next and they allow us to attribute behavior to a person’s being ‘in a stage’. These theories offered the security of understanding human behavior in a time of rapid change during industrialization in the early 1900s. Science seemed to be laying a predictable groundwork we could rely upon. But these early theories also implied that those who did not progress through stages in the predictable way were delayed somehow and this led to the idea that development had to occur in a patterned way.

Today we understand that development does not occur in a straight line. Sometimes we change in many directions depending on our experiences and surroundings. For example, there can be growth and decline in cognitive functioning at any age depending on nutrition, health, activity, and stimulation. And that both nature (heredity) and nurture (the environment) shape our abilities throughout life. Some things about us are continuous such as our temperament or sense of self, perhaps. And we may revisit a stage of life more than once. For instance, Erikson suggests that we struggle with trust as infants and then begin to focus more on independence or autonomy. But if we are in circumstances in which our independence is jeopardized, such as becoming physically dependent, we may struggle with trust again. Keep these thoughts in mind as we explore stage theories in our next lesson.

The study of human development is based on research. Let’s look at the methods used to understand development. In other words, how do we know what we know?

All of us know some things about human development. But how do we know these things? Very often, it’s a matter of personal knowledge. I have ideas about children, largely based on my experiences with my own two daughters. I know about myself because of what I’ve been through. So it’s based on what I know directly, personally. But there are problems with personal knowledge. Ever hear the expression, “Seeing is believing”? It suggests that in order to know something, I have to see it.

But social psychologists tell us that this is not how the mind works. Typically, we have a belief about something and that belief guides what we perceive. (So for example, if I believe that teenagers are argumentative, I’m more likely to notice when my teenaged daughter is in a bad mood or is argumentative than when she’s compliant and happy.) Science is designed to get us to be more objective in what we observe to get out of the ‘believing is seeing’ trap.

Confirmation bias is the tendency to look for evidence that we are right. This bias can keep us from seeing what is really going on when working with patients, or students, or anyone else. Practitioners, for example, can get used to seeing a certain kind of cases and assume that anyone with the same set of symptoms must also have the same illness. Sometimes this can get in the way of delivering an accurate diagnosis. An example that comes to mind is one in which a 40 year old woman who was very thin wasn’t diagnosed as anorexic for some time because of her age. But, in fact, anorexia was the problem. The clinician assumed that anorexia was only found in younger women. Sampling bias is the tendency to get information from people who are accessible or close to us when trying to find out about how the world works. If I ask those who live and work with me about parenting, or health, or love, I’m going to find out about their situations but not about the views of those unlike me who live and work outside my boundaries. As a result, my knowledge is biased and incomplete.

Have you ever heard of the “scientific method”? Chances are, if you have, you’ve heard of the quantitative method. It involves a set of procedures ultimately designed to give numeric expression to a phenomenon or to quantify what is happening and perhaps, to test whether or not what is happening could be due to chance. Quantitative methods involve beginning with a research question, reviewing the literature to see what others have found in their research of the topic, determining specifically what aspect of the topic to explore in your research and determining the most appropriate method to use for your purposes, conducting the study, which means finding your sample, administering your survey or conducting your experiments, interpreting the results by analyzing your data, drawing conclusions about what you have found, and finally sharing your findings with others in the scientific community by publishing your research. This method has been favored in the scientific community for some time. It has been viewed as the most scientifically rigorous.

Qualitative methods of research involve using a more open, evolving approach to finding out about the world. There is less emphasis on quantifying what is known and more emphasis on tapping into the experiences, assumptions, and meanings subjects give to their situations. Qualitative methods can be used to explore an area about which little is known or to get a fresh look at a situation that has been studied before. The use of narratives in which the researcher tries to find out what is going on by using the subjects’ own words is one approach. Qualitative methods are used in anthropology, education, nursing, and other areas where the researcher wishes to be led by the participants into seeing what they deem as important.

The researcher begins with a broad interest and gains entrance into a setting in which to explore. Information is gathered using a variety of techniques such as observation, documenting the physical space and surroundings of that setting, recording interviews, etc. After gathering general information, the researcher may decide to focus more closely on specific research questions. Patterns may become apparent as the researcher revisits their field notes and spends more time in a setting. These prompt the researcher to explore new ideas until they feel they reach a point of saturation, or a feeling that they’ve thoroughly explored the situation. Patterns and answers to research questions are noted in a report of the findings.

Let’s explore types of research or research designs. These are several ways in which researchers gather information. All have advantages and disadvantages.

Some advantages of this method include:

You observe behavior in the natural environment. Our surroundings often shape our behavior.
You can see what people do rather than relying on them to tell you what they do.
You can generate hypotheses that can guide future research.

Disadvantages include:

Because you have not randomly selected your sample to observe, you cannot make general statements from your findings. In other words, if I observe children on a playground in a small community in the Pacific Northwest, I can’t assume that all children will behave in a similar manner.
Observational studies are often descriptive only. They allow us to describe behavior, but not to explain why something has occurred.

In research, concepts or ideas take the form of variables. Variables are factors that change in value. An independent variable is one that is controlled by or introduced by the researcher. In experimental research, it is a potential causal variable. In other words, it introduced to see if it brings about a change or effect. (Keep in mind that not all independent variables are causal. Some are correlational meaning they are related to another factor, but haven’t been established as the cause of change in the other factor.)

Dependent variables are outcomes. They tend to be what the research is all about. They are called dependent because their value depends on what has been introduced.

The primary advantage of the experimental design is its ability to isolate cause and effect relationships. In order to establish a cause and effect relationship between variables, three conditions have to be met. First, the independent and dependent variable have to be related in some way. For example, if the independent variable is increased or decreased, the dependent variable must change in some way. Correlational studies focus on these relationships. Second, the independent variable must come before the dependent variable. What aspect of experimental design tells us that the independent variable had to be introduced before the dependent variable could change? Finally, we have to know that there is no outside cause creating the change that we see. What aspect of experimental design helps us to eliminate outside or unknown causes? The disadvantages of experimental design include the Hawthorne Effect and the potential difficulty in creating real life situations in an artificial, laboratory environment. For example, can we recreate in a laboratory setting the altruism that people exhibit toward one another after a natural disaster?

Case studies involve focusing attention on a single person or situation. The researcher gathers information in a variety of ways to find out as much as possible about the case. Clinicians, whether they are physicians, nurses, social workers, or psychotherapists often use a modified case study approach when finding out about a patient or client. They observe behavior, administer tests, and interview the person to gather information. The case study method of research is often used by clinicians too.

Case studies are a good way to explore unusual situations and can provide a basis for hypotheses that can be tested in other research. Confirmation bias can occur when clinicians trained to see a particular problem see it even when it isn’t there. For example, psychotherapists are often trained to see psychopathology in those they serve. As a result, they may miss seeing what’s right with a person. Surveys involve asking a standard or consistent set of questions with a sample of people from the population of interest. Those who answer the survey are often given a set of responses from which to choose.

Surveys are used a lot because they allow you to reach a large number of people in a limited amount of time. The use of internet, telephone, and mail allow the researcher to gather information from people far and near. Disadvantages of surveys include their reliance on self-report. In other words, the people answering the survey are reporting on their behavior and sometimes what we say we do is not the same as what we actually do. It’s difficult to survey people about sensitive topics. Participants may be reluctant to give honest answers about activities that are stigmatized. And survey questions have to be worded carefully in order to not bias the answers given. These questions need to be worded in a neutral way to give ‘permission’ to answer candidly. The responses available must be thorough as well so that participants feel comfortable in choosing a response.

Secondary or content analysis involves analyzing information that has already been collected whether that is in the media or through another agency that gathers data, such as the census.

One of the clearest advantages is the time saved from not having to recruit participants and gather information from them. But if the data that has been gathered by someone else is faulty in some way, for example inaccurate, the results drawn through secondary analysis will also be faulty. And an analysis of media may not accurately reflect people’s actual behavior or attitudes.

Some research designs that are especially useful in studying human development include cross-sectional, longitudinal, and cross-sequential designs. Cross-sectional research involves looking at a varied group (representing gender, race, age groups, etc.) at one point in time. Longitudinal research involves following a particular group over a long period of time. Cross-sequential research involves following a varied group over a long period of time. What would be the advantages and disadvantages of each?

Introduction to Lifespan Psychology. Authored by : Laura Overstreet. Located at : http://youtu.be/akcTT_3uXXo?list=UURGwdSbeKDiBnjRoSpiPVHA . License : Other . License Terms : Standard YouTube license

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Case Studies in Lifespan Development

Stephanie M. Wright - Georgia Gwinnett College Psychology Department
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Lifespan Development: Lives in Context, Second Edition : Chronologically organized, this book explores the dynamic interactions between individuals, our genetic makeup, and the diverse contexts that shape our growth and development at every stage of life.
Lifespan Development in Context: A Topical Approach: Provides a panoramic view of the many influences that shape human development.
Child Development From Infancy to Adolescence: An Active Learning Approach, Second Edition : Chronologically organized, this book presents topics within the field of child development through unique and highly engaging Active Learning opportunities.

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Module 1: Lifespan Development

Research methods, learning outcomes.

Describe methods for collecting research data (including observation, survey, case study, content analysis, and secondary content analysis)

We have just learned about some of the various models and objectives of research in lifespan development. Now we’ll dig deeper to understand the methods and techniques used to describe, explain, or evaluate behavior.

All types of research methods have unique strengths and weaknesses, and each method may only be appropriate for certain types of research questions. For example, studies that rely primarily on observation produce incredible amounts of information, but the ability to apply this information to the larger population is somewhat limited because of small sample sizes. Survey research, on the other hand, allows researchers to easily collect data from relatively large samples. While this allows for results to be generalized to the larger population more easily, the information that can be collected on any given survey is somewhat limited and subject to problems associated with any type of self-reported data. Some researchers conduct archival research by using existing records. While this can be a fairly inexpensive way to collect data that can provide insight into a number of research questions, researchers using this approach have no control on how or what kind of data was collected.

Types of Descriptive Research

Observation.

Observational studies , also called naturalistic observation, involve watching and recording the actions of participants. This may take place in the natural setting, such as observing children at play in a park, or behind a one-way glass while children are at play in a laboratory playroom. The researcher may follow a checklist and record the frequency and duration of events (perhaps how many conflicts occur among 2-year-olds) or may observe and record as much as possible about an event as a participant (such as attending an Alcoholics Anonymous meeting and recording the slogans on the walls, the structure of the meeting, the expressions commonly used, etc.). The researcher may be a participant or a non-participant. What would be the strengths of being a participant? What would be the weaknesses?

In general, observational studies have the strength of allowing the researcher to see how people behave rather than relying on self-report. One weakness of self-report studies is that what people do and what they say they do are often very different. A major weakness of observational studies is that they do not allow the researcher to explain causal relationships. Yet, observational studies are useful and widely used when studying children. It is important to remember that most people tend to change their behavior when they know they are being watched (known as the Hawthorne effect ) and children may not survey well.

Case Studies

Case studies involve exploring a single case or situation in great detail. Information may be gathered with the use of observation, interviews, testing, or other methods to uncover as much as possible about a person or situation. Case studies are helpful when investigating unusual situations such as brain trauma or children reared in isolation. And they are often used by clinicians who conduct case studies as part of their normal practice when gathering information about a client or patient coming in for treatment. Case studies can be used to explore areas about which little is known and can provide rich detail about situations or conditions. However, the findings from case studies cannot be generalized or applied to larger populations; this is because cases are not randomly selected and no control group is used for comparison. (Read The Man Who Mistook His Wife for a Hat by Dr. Oliver Sacks as a good example of the case study approach.)

A person is checking off boxes on a paper survey

Figure 1. A survey is a common tool for collecting research data.

Surveys are familiar to most people because they are so widely used. Surveys enhance accessibility to subjects because they can be conducted in person, over the phone, through the mail, or online. A survey involves asking a standard set of questions to a group of subjects. In a highly structured survey, subjects are forced to choose from a response set such as “strongly disagree, disagree, undecided, agree, strongly agree”; or “0, 1-5, 6-10, etc.” Surveys are commonly used by sociologists, marketing researchers, political scientists, therapists, and others to gather information on many variables in a relatively short period of time. Surveys typically yield surface information on a wide variety of factors, but may not allow for an in-depth understanding of human behavior.

Of course, surveys can be designed in a number of ways. They may include forced-choice questions and semi-structured questions in which the researcher allows the respondent to describe or give details about certain events. One of the most difficult aspects of designing a good survey is wording questions in an unbiased way and asking the right questions so that respondents can give a clear response rather than choosing “undecided” each time. Knowing that 30% of respondents are undecided is of little use! So a lot of time and effort should be placed on the construction of survey items. One of the benefits of having forced-choice items is that each response is coded so that the results can be quickly entered and analyzed using statistical software. The analysis takes much longer when respondents give lengthy responses that must be analyzed in a different way. Surveys are useful in examining stated values, attitudes, opinions, and reporting on practices. However, they are based on self-report, or what people say they do rather than on observation, and this can limit accuracy. Validity refers to accuracy and reliability refers to consistency in responses to tests and other measures; great care is taken to ensure the validity and reliability of surveys.

In this video, Harvard psychologist Dan Gilbert explains survey research that was conducted to explore the way our preferences change over time.

You can view the transcript for “The psychology of your future self | Dan Gilbert” here (opens in new window) .

Content Analysis

Content analysis involves looking at media such as old texts, pictures, commercials, lyrics or other materials to explore patterns or themes in culture. An example of content analysis is the classic history of childhood by Aries (1962) called “Centuries of Childhood” or the analysis of television commercials for sexual or violent content or for ageism. Passages in text or television programs can be randomly selected for analysis as well. Again, one advantage of analyzing work such as this is that the researcher does not have to go through the time and expense of finding respondents, but the researcher cannot know how accurately the media reflects the actions and sentiments of the population.

Secondary content analysis, or archival research, involves analyzing information that has already been collected or examining documents or media to uncover attitudes, practices or preferences. There are a number of data sets available to those who wish to conduct this type of research. The researcher conducting secondary analysis does not have to recruit subjects but does need to know the quality of the information collected in the original study. And unfortunately, the researcher is limited to the questions asked and data collected originally.

Link to Learning

U.S. Census Data is available and widely used to look at trends and changes taking place in the United States (visit the United States Census website and check it out). There are also a number of other agencies that collect data on family life, sexuality, and on many other areas of interest in human development (go to the NORC at the University of Chicago website or the Henry J Kaiser Family Foundation website and see what you find.).

Case Studies in Lifespan Development

Stephanie M. Wright - Georgia Gwinnett College Psychology Department
Description

Lifespan Development: Lives in Context, Second Edition : Chronologically organized, this book explores the dynamic interactions between individuals, our genetic makeup, and the diverse contexts that shape our growth and development at every stage of life.
Lifespan Development in Context: A Topical Approach: Provides a panoramic view of the many influences that shape human development.
Child Development From Infancy to Adolescence: An Active Learning Approach, Second Edition : Chronologically organized, this book presents topics within the field of child development through unique and highly engaging Active Learning opportunities.

Should you need additional information or have questions regarding the HEOA information provided for this title, including what is new to this edition, please email [email protected] . Please include your name, contact information, and the name of the title for which you would like more information. For information on the HEOA, please go to http://ed.gov/policy/highered/leg/hea08/index.html .

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KEY FEATURES:

SAGE coursepacks LMS resources for these texts include auto-graded assessments and open-ended discussion questions.
Each case portrays a different context than the others , reinforcing for students the effects of diverse environments on human development.
Wide diversity among cases exposes students to development within periods and domains from differing genetic and cultural contexts.
Cases develop from conception through end-of-life to encourage analysis of early life experiences as precursors to later life development.
Comprehensive assessment requires students to create new case outcomes from existing theory and information.
Specific learning objectives for each domain and period of development are presented at the beginning of each developmental moment and are mapped to primary text material.

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Lifespan Developmental Research Methodologies

Ellen Skinner; Julia Dancis; and The Human Development Teaching & Learning Group

Learning Objectives: Lifespan Developmental Methodologies

Explain the importance of complementary multidisciplinary methodologies and converging operations.
Recognize the steps in deductive , inductive , and collaborative methodologies.
Be familiar with the many methods developmentalists use to gather information, including observations and self-reports, psychological tests and assessments, laboratory tasks, psychophysiological assessments, archival data or artifacts, case studies, and enthnographies.
Identify the general strengths and limitations of different methods (e.g., reactivity, social desirability, accessibility, generalizability).

Because interventionists and practitioners use bodies of scientific evidence to transform systems and change practices in the world, it is crucial that researchers produce the highest quality evidence possible, and evaluate and critique it thoughtfully. The tools that scientists use to generate such knowledge are called research methods or methodologies. Many textbooks describe “the” scientific method, as if there were only one way of knowing scientifically. Just as lifespan development spans multiple disciplines, each with their own preferred epistemologies and methodologies, we believe that there are multiple scientific methods, or multiple perspectives, each one providing a complementary line of sight on a given target phenomenon. Social and developmental sciences have been critiqued for our reliance on a narrow range of methodologies, favoring methods that quantify observations (e.g., via surveys, ratings, or numerical codings) and control extraneous variables or confounds, either statistically or, for example, by bringing people into the lab. Social scientists often seem to favor these more quantitative methods, and to discount methodologies that are more situated, contextualized, and wholistic, sometimes called qualitative methods.

An illustration of four men touching an elephant, demonstrating the parable of the blind men and the elephant

However, it has become clear that these methodologies are not antagonistic. Instead, they are complementary ways of knowing or lines of sight on target phenomena, each whole and important in its own right, but incomplete. We think about these multiple perspectives the same way that they are described in the parable of the six blind men and the elephant. In this story, each person makes contact with a different part of the elephant and comes to his own conclusions– the one who encounters its legs explains that elephants are tree trunks, the ears reveal it to be a fan, the flank a wall, the tail a rope, the trunk a snake, and the tusk a spear.

Each one’s understanding is correct, but unknown to all of them, each is also incomplete. They need the views from all of these perspectives, what we sometimes call 360 o lines of sight, to fully appreciate the elephant in its wholeness and complexity. In the same way, multiple cross-disciplinary, inter-disciplinary, and multi-disciplinary methodologies are needed to understand our developmental phenomena in their wholeness and complexity. We find a lifespan developmental systems perspective especially useful in articulating this view (Baltes, Reese, & Nesselroade, 1977; Cairns, Elder, & Costello, 2001; Lerner, 2006; Overton, 2010; Overton & Molenaar, 2015; Skinner, Kindermann, & Mashburn, 2019). The best research and graduate training programs in human development teach their doctoral students about a wide range of epistemologies and methodologies and see them all as parts of “ converging operations .”

What is meant by converging operations?

This was an idea, brought to the attention of developmentalists almost 50 years ago (Baer, 1973), to help deal with the unsettling realization that every method ever devised to conduct scientific studies has serious shortcomings. The main idea is that good science needs a wide variety of differing methodologies, so that the strengths of one can compensate for the limitations of others. From this perspective, a body of evidence is much stronger when findings from multiple complementary methodologies converge on the same conclusions. That is why we favor developmental science that incorporates methodologies from many disciplines, and continues to question and critique those methodologies as part of its reflective practice.

Deductive Methodologies

In discussions of scientific methods, the procedure that is often highlighted is the deductive method — in which a scientist starts with a falsifiable hypothesis and then conducts a series of observations to test whether the specifics on the ground are consistent with this hypothesis. In this process, the scientist foregrounds “thinking” (the theory) and follows this up with figuring out how to “look” (i.e., conduct the study or observation) in ways that test the validity of this theory. This process unfolds in multiple recursive or circular steps, including:

Review previous studies (known as a literature review) to determine what has been found to date
Identify the deficiencies or gaps in previous research
Formulate a working theory of the target phenomenon and propose a hypothesis
Who? Sampling . Determine the people to be included
What? Measurement . Determine the measures to be used to capture the phenomena of interest
Where? Setting . Determine the setting where the study will take place
How? and When? Design . Determine the study design
Consider the limitations of the study
Draw conclusions, including rejecting the hypothesis and revising the original theory
Suggest future studies
Share information with the scientific community
Invite scrutiny of work by other experts

Inductive Methodologies

A second set of procedures is more inductive . This process, often called grounded theory , starts with a general question and then constructs a theory of the phenomenon based, not on the scientific community’s or researcher’s preconceived notions, but on the researcher’s actual observations of many specific experiences on the ground. As you can see, in the process, the scientist foregrounds “looking” (the observations and experiences in the target setting) and uses this process to scaffold “thinking” (i.e., theorizing or building a mental model of what has been observed). This process also unfolds in multiple recursive or circular steps, including:

Review the literature to justify the importance of the problem
See how the problem fits into a larger set of issues
Identify the deficiencies or gaps in other work on the topic
Who? and Where? Gain entrance into a group and natural setting relevant to the problem of study
What? Ask open-ended, broad “grand tour” types of questions when interviewing and observing participants; focus on participant perspectives
How? Gather field notes about the setting, the people, the structure, the activities or other areas of interest; collect artifacts, pictures
Reflect . Modify research questions as the study evolves and follow the emergent questions
Note own participation and biases
Note patterns or consistencies, uncover themes, categories, interrelationships
Focus on centrality of meaning of the participants
Explore new areas deemed important by participants
Check back in with participants to get their perspectives on your interpretations

Collaborative Methodologies

A third set of methodologies is based on the assumption that knowledge, research, and effective social action can best be co-constructed among researchers and community participants, incorporating the strengths and perspectives of all the stakeholders involved in a particular set of issues. This approach, often called community-based participatory action research , holds that complex social issues cannot be well understood or resolved by “expert” research, pointing to interventions from outside of the community which often have disappointing results or unintended side effects. In collaborative approaches, researchers and community partners build a genuine trusting relationship, and this cooperative partnership is the basis on which all decisions about the project are made: from articulating a set of research questions, to identifying data collection strategies, analysis and interpretation of information, and dissemination and application of findings.

The process is inherently:

Community-based. Researchers build a collaborative partnership with community members who are already living with, involved in, or working on the problem of interest. Hence, this work is situated within neighborhoods and community organizations or groups, and builds on their strengths and priorities. Instead of taking individuals out of communities and into lab settings for study or providing individualized therapy to “fix” broken individuals, the goal of this work is to help facilitate change within the community itself, making it a more supportive context for all its inhabitants.
Participatory . As the collaboration develops, members discuss and learn more about each other so that together they can co-create and frame a common agenda for research and action. These projects incorporate researchers’ expertise and goals, but they foreground the knowledge, concerns, and needs of community partners. For example, researchers interested in homeless youth could reach out to youth-serving organizations and begin conversations exploring whether they would like to work together. These conversations would also soon involve the homeless youth themselves, consistent with the slogan popularized by the disability rights movement, “Nothing about us without us!” Community knowledge is considered irreplaceable as it provides key insights about target issues.
Action. All research activities are anchored and oriented by the larger goal of enhancing strategic action that leads to social change and community transformation as part of the research program. Community action make take the form of public education surrounding community issues (e.g., information campaigns, teach-ins), changing existing policies that harm groups of people (e.g., harsh discipline policies at school), creating new public spaces (e.g., community gardens and farmers’ markets), and so on.
Research. The community action plan is informed by organizing existing information and collecting new information from key stakeholders relevant to the community issues under scrutiny. Methods to conduct these studies are planned together in ways that researchers believe will produce high quality information and that collaborators believe will be useful to them in making progress on their agenda. All partners are also involved in the scrutiny, visualization, discussion, and interpretation of data, and make joint decisions about how it should be disseminated and used going forward. These efforts feed into next steps in both research and action.
Ongoing collaboration. Such university-community partnerships typically last for many years. Researchers are thoughtful about how to bring them successfully to a close, making sure that an ongoing goal of the collaboration is to build capacity within the community partnership so members can sustain collective action after the research team leaves.

A good way to become more familiar with these collaborative, inductive, and deductive research methods is to look at journal articles. You will see that they are written in sections that follow the steps in the scientific process. In general, the structure includes: (1) abstract (summary of the article), (2) introduction or literature review, (3) methods explaining how the study was conducted, (4) results of the study, (5) discussion and interpretation of findings, and (6) references (a list of studies cited in the article).

Methods of Gathering Information

“Methods” is also a name given to many different procedures scientists use to make their observations or collect information. Since developmentalists are interested in a wide range of human capacities, they want to know not only about people’s actions and thoughts, as expressed in words and deeds, but also about underlying processes, like abilities, emotions, desires, intentions, and motivations. Moreover, they want to go deeper, looking into biological and neurophysiological processes, and they want to consider many factors outside the person of study, looking at social relationships and interactions, as well as environmental materials, tasks, and affordances, and societal contexts. And, as lifespan researchers, they want to study these capacities at all ages, from the tiniest babies to the oldest grandmothers. No wonder developmental scientists need so many tools, and are inventing more all the time.

Every time you come across a conclusion in a textbook or research article (for example, when you read that “18-month-olds do not yet have a sense of self”), you should stop and ask, “How do you know that?” That is a great question. And a great scientific attitude. Over and over, we will want to scrutinize the evidence scientists are using to make their conclusions, considering carefully the extent to which the methods scientists use justify the conclusions they make. If a baby can’t yet talk, how would we know whether they have a sense of self? And even when a child can talk, what is the connection between what they are telling us and what they are truly thinking? You can be sure that these kinds of questions stoke lively debates in scientific circles.

As with methodologies more generally, science is strengthened by the use of a variety of approaches to collecting information. The shortcomings of one can be compensated for by the strengths of others. If we find that a new mother says that she is feeling stressed, and her best friend agrees, and we see elevated cortisol levels, and her survey results are higher than usual, and she becomes irritated when her two-year-old makes a mess– well, we think we have captured something meaningful here. We are always in favor of multiple sources of data, and we especially appreciate methods that get us thick, rich information, as close to lived experience in context as possible.

Here are some examples of methods commonly used in developmental research today:

Observations: Looking at People and their Actions

Often considered the basic building blocks of developmental science, observational methods are those in which the researcher carefully watches participants, noting what they are doing, saying, and expressing, both verbally and nonverbally. Researchers can observe participants doing just about anything, including working on tasks, playing with toys, reading the newspaper, or interacting with others. Observations are ideal for gathering information about people’s verbal and physical behavior, but it is less clear whether internal states, like emotions and intentions, can be unambiguously discerned through observation.

Naturalistic observations take place when researchers conduct observations in the regular settings of everyday life. This method allows researchers to get very close to the phenomenon as it actually unfolds, but researchers worry that their participation may impact participants’ behaviors (a problem called reactivity ). And, since researchers have little control over the environment, they realize that the different behaviors they observe may be due to differences in situational factors.
Laboratory observations , in contrast, take place in a specialized setting created by the researcher, that is, the lab. For example, researchers bring babies and their caregivers to the lab in a systematic procedure known as the strange situation, which you will learn about in the section on attachment. Observing in the lab allows researchers to set up a specific space and to have control over situational factors. However, researchers worry that the artificial nature of the situation may have an impact on people’s behavior, and that the behaviors people show in the lab are not typical of the ones they show in regular contexts of daily life (a problem called generalizability ).
Video or audio observations can be gathered using automatic recording devices that collect information even when a researcher is not present. For example, researchers ask caregivers to record family dinners or teachers to tape class sessions; or place a small recording device on a young child’s chest that records every word the child says or hears. These records can then be watched or listened to by researchers. Such procedures reduce reactivity, but the resultant recordings are narrower in scope than what researchers could hear or see if they were present observing in the actual context.
Local expert observers can provide researchers with information about the verbal and non-verbal behavior of participants they have observed or interacted with many times. For example, caregivers and teachers can report on their children and students, and even children can provide their perspectives. Reports from others typically incorporate many more observations than a researcher could collect (e.g., a teacher sees a child in class every week day), so the information is more representative of the target’s typical behavior. However, researchers worry that information could be distorted, for example, because reporters are biased or are not trained to observe or categorize the behaviors they have witnessed.
Participant observations, which are especially common in anthropology and sociology, take place when researchers gain entrance into a setting, not as an observer, but as a participant, with the aim of gaining a close and intimate familiarity with a given group of individuals or a particular community, and their behaviors, relationships, and practices. These observations are usually conducted over an extended period of time, sometimes months or years, which means that the observer can directly observe variations and changes in actions and interactions. Such observations provide rich and detailed information, but are limited to the specific setting.

Self-reports: Listening to People and their Thoughts

When researchers are studying people, one of the most common ways of gathering information about them is by asking them, via self-report methods. These can range from informal open-ended interviews or requests for participants to write responses to prompts, all the way to surveys, when participants can only choose among researcher-generated options. Self-report data are ideal for learning about people’s inner thoughts or opinions, but researchers worry that participants may distort the truth to present themselves in a favorable light (a problem called social desirability ). There is also debate about whether participants have access to some of their internal processes, like their genuine motivations.

Surveys gather information using standardized questionnaires, which can be administered either verbally or in writing. Surveys capture an enormous range of psychological and social processes, and their items can be tested for their reliability and validity (called psychometric properties ), but they typically yield only surface information. Researchers worry that participants may misinterpret questions and realize that the information so collected is restricted to exactly those pre-packaged questions and responses.
Standardized, structured, or semi-structured interviews involve researchers directly asking a series of predetermined questions. Because researchers are present, they can ask follow up questions and participants can ask for clarification. This allows researchers to learn more from participants than they could from standardized questionnaires, but researchers worry that their presence could cause reactivity , such as when participants want to provide more socially desirable responses in a face-to-face setting than on an anonymous survey.
Open-ended interviews typically use targeted questions or prompts to get the conversation flowing, and then follow the interview where ever it leads. This allows for more customized questioning and in-depth answers, as researchers probe responses for greater clarity and understanding. However, since each respondent participates in a different interview conversation, it can be difficult to compare responses from person to person.
Focus groups involve group open-ended interviews, in which a small number of people (6-10) discuss a series of questions or prompts in guided or open discussion with a trained facilitator. In this format, focus group members listen and can react to each other’s comments and build discussion at the group level.
Responses to prompts are used when researchers ask participants to write down their thoughts. These can range from relatively unstructured free writes to short answers to a series of well-structured questions. Daily diaries , often organized electronically, allow participants to respond to online questions or prompts many days in a row.

Psychological Tests and Assessments: Mental Capacities and Conditions

Most of us are familiar with tests that measure, for example, IQ or other mental abilities, and with diagnostic assessments that classify people according to psychological conditions. When you read about the aging of intelligence, for example, some of those studies utilize measures of crystalized and fluid intelligence. Tests to measure mental abilities have been created for people of all ages, although it is not always clear how the measures used at different ages are connected to each other.

Laboratory Tasks: Interactions that Elicit or Capture Psychological Processes

Researchers create and invent all manner of tasks for participants to work on, either in the lab or in real life settings (e.g., at home or school). These tasks allow researchers to set up activities that can assess a range of psychological attributes for people of all ages, ranging from problem-solving abilities to regulatory capacities (e.g., using the “ Heads, Shoulders, Knees, and Toes ” task), prosocial behaviors, learned helplessness, theories of mind, social information processing, rejection sensitivity, and so on. Many YouTube videos show children and adolescents participating in these tasks, and it is instructive to try to figure out exactly what is captured in each one. If you would like to see an example, you can watch a video of The Shopping Cart Study (not required, bonus information).

Psychophysiological Assessment: Underlying Neurophysiological Functioning

Researchers also use a range of methods to capture information about neurophysiological functioning across the lifespan, including technology that can measure heart rate, blood pressure, hormone levels, and many kinds of brain activity to help explain development. These assessments provide information about what is happening “under the skin,” and researchers can see how these biological processes are connected to behavioral development. Usually connections are bidirectional– neurophysiology contributes to the development of behavior, and behaviors shape physiological functioning and development.

Archival Data or Artifacts: Information from Business as Usual

Researchers sometimes utilize information that has already been collected as a regular part of daily life. Such data include, for example, students’ grades and achievement tests scores, documents or other media, drawings, work products, or other materials that might provide information about participants’ developmental progress or causal factors contributing to their development. These kinds of data have the advantage of low reactivity and high authenticity, in that they were created or gathered in the normal course of events, but it is sometimes unclear exactly what they mean or what constructs they measure.

Case Study: All of the Above with Carefully Selected Participants or Settings

One of the best ways to gather in depth information about a person or group of people (e.g., a classroom, school, or neighborhood) is through a research methodology called the case study . Researchers focus on only one or a small number of target units, usually carefully selected for specific characteristics (e.g., an individual identified as wise, a homeless teenager, a very effective school, or a workplace with high turnover rates), and amass everything they can about that person or place. Researchers typically conduct in-depth open-ended interviews with people, including friends or family of the target person, and collect archival data and artifacts, which they might discuss in depth with participants. For example, they might go through the person’s photo albums and discuss memories of their early life. Classical examples of case studies are the so-called baby diaries , in which researchers like Jean Piaget and William Stern conducted extensive observations on their individual children and took detailed notes about every aspect of their behavior and development. They also tested some of their hypotheses about development, by giving their babies toys to play with or engaging them in interesting tasks. These case studies were conducted over years. When case studies also extend into the past of the individual (for example, when researchers are interested in life review processes), they can be called biographical methods .

Sometimes researchers who focus on a group of individuals or a setting are particularly interested in the cultural context and its functioning. These studies can be called ethnographies . Drawn originally from anthropology, ethnographic methods describe an approach in which researchers carefully study and document people and their cultural settings, usually through extensive participant-observation, interviews, and engagement in the setting. In these studies, as in all scientific investigations, researchers are the students and the people in the setting are the teachers. Researchers strive to create a wholistic, higher-order narrative account that privileges the perspectives of the people studied.

Take Home Messages about Lifespan Developmental Methodologies

We would highlight four main themes from this section:

Because interventionists and practitioners use bodies of scientific evidence to transform systems and change practices in the world, it is crucial that researchers produce the highest quality evidence possible , and evaluate and critique it thoughtfully.
Developmental science incorporates multiple methodologies from many disciplines, and these deductive, inductive, and collaborative methodologies make our conclusions stronger because they provide complementary lines of sight on our target phenomena.
Science is also strengthened by the use of a variety of approaches (or methods) for collecting information , including observations, self-reports, and other strategies, because together they provide a richer picture of our target developing phenomena.
The advantages of using multiple methodologies and sources of information are highlighted by the idea of “ converging operations, ” which points out that this practice allows the shortcomings of one method to be compensated for by the strengths of others, and reminds us that bodies of evidence are stronger when findings from multiple complementary methodologies and sources of information converge on the same conclusions.

Baer, D. M. (1973). The control of developmental process: Why wait? In J. R. Nesselroade & H. W. Reese (Eds.), Lifespan developmental psychology: Methodological issues (pp. 187-193). New York: Academic Press.

Baltes, P. B., Reese, H. W., & Nesselroade, J. R. (1977). Life-span developmental psychology: Introduction to research methods . Oxford, England: Brooks/Cole.

Cairns, R. B., Elder, G. H., & Costello, E. J. (Eds.). (2001). Developmental science . New York: Cambridge University Press.

Lerner, R. M. (2006). Developmental science, developmental systems, and contemporary theories of human development. In R. M. Lerner (Vol. Ed.) and R. M. Lerner & W. E. Damon (Eds-in-Chief.). Handbook of child psychology: Vol 1, Theoretical models of human development (pp. 1-17). John Wiley & Sons Inc.

Overton, W. F. (2010). Life‐span development: Concepts and issues. In W. F. Overton (Vol. Ed.) R.M. Lerner (Ed.-in-Chief), The handbook of life-span development: Vol. 1. Cognition, biology, and methods (pp. 1-29). Hoboken, NJ: Wiley.

Overton, W. F., & Molenaar, P. (2015). Handbook of child psychology and developmental science (R. M. Lerner, Ed.-in-Chief) : Vol 1, Theory and method . John Wiley & Sons Inc.

Skinner, E. A., Kindermann, & Mashburn, A. J. (2019). Lifespan developmental systems: Meta-theory, methodology, and the study of applied problems. An Advanced Textbook . New York, NY: Routledge.

Media Attributions

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Research in Lifespan Development

What you’ll learn to do: examine how to do research in lifespan development.

Desk shown from above, pair of hands seen gesturing towards a graph

How do we know what changes and stays the same (and when and why) in lifespan development? We rely on research that utilizes the scientific method so that we can have confidence in the findings. How data are collected may vary by age group and by the type of information sought. The developmental design (for example, following individuals as they age over time or comparing individuals of different ages at one point in time) will affect the data and the conclusions that can be drawn from them about actual age changes. What do you think are the particular challenges or issues in conducting developmental research, such as with infants and children? Read on to learn more.

Learning Outcomes

Explain how the scientific method is used in researching development
Compare various types and objectives of developmental research
Describe methods for collecting research data (including observation, survey, case study, content analysis, and secondary content analysis)
Explain correlational research
Describe the value of experimental research
Compare advantages and disadvantages of developmental research designs (cross-sectional, longitudinal, and sequential)
Describe challenges associated with conducting research in lifespan development

How do we know what we know?

An important part of learning any science is having a basic knowledge of the techniques used in gathering information. The hallmark of scientific investigation is that of following a set of procedures designed to keep questioning or skepticism alive while describing, explaining, or testing any phenomenon. Not long ago a friend said to me that he did not trust academicians or researchers because they always seem to change their story. That, however, is exactly what science is all about; it involves continuously renewing our understanding of the subjects in question and an ongoing investigation of how and why events occur. Science is a vehicle for going on a never-ending journey. In the area of development, we have seen changes in recommendations for nutrition, in explanations of psychological states as people age, and in parenting advice. So think of learning about human development as a lifelong endeavor.

Personal Knowledge

How do we know what we know? Take a moment to write down two things that you know about childhood. Okay. Now, how do you know? Chances are you know these things based on your own history (experiential reality), what others have told you, or cultural ideas (agreement reality) (Seccombe and Warner, 2004). There are several problems with personal inquiry, or drawing conclusions based on our personal experiences.

Read the following sentence aloud:

Paris in the the spring

Are you sure that is what it said? Read it again:

If you read it differently the second time (adding the second “the”) you just experienced one of the problems with relying on personal inquiry; that is, the tendency to see what we believe. Our assumptions very often guide our perceptions, consequently, when we believe something, we tend to see it even if it is not there. Have you heard the saying, “seeing is believing”? Well, the truth is just the opposite: believing is seeing. This problem may just be a result of cognitive ‘blinders’ or it may be part of a more conscious attempt to support our own views. Confirmation bias is the tendency to look for evidence that we are right and in so doing, we ignore contradictory evidence.

Philosopher Karl Popper suggested that the distinction between that which is scientific and that which is unscientific is that science is falsifiable; scientific inquiry involves attempts to reject or refute a theory or set of assumptions (Thornton, 2005). A theory that cannot be falsified is not scientific. And much of what we do in personal inquiry involves drawing conclusions based on what we have personally experienced or validating our own experience by discussing what we think is true with others who share the same views.

Science offers a more systematic way to make comparisons and guard against bias. One technique used to avoid sampling bias is to select participants for a study in a random way. This means using a technique to ensure that all members have an equal chance of being selected. Simple random sampling may involve using a set of random numbers as a guide in determining who is to be selected. For example, if we have a list of 400 people and wish to randomly select a smaller group or sample to be studied, we use a list of random numbers and select the case that corresponds with that number (Case 39, 3, 217, etc.). This is preferable to asking only those individuals with whom we are familiar to participate in a study; if we conveniently chose only people we know, we know nothing about those who had no opportunity to be selected. There are many more elaborate techniques that can be used to obtain samples that represent the composition of the population we are studying. But even though a randomly selected representative sample is preferable, it is not always used because of costs and other limitations. As a consumer of research, however, you should know how the sample was obtained and keep this in mind when interpreting results. It is possible that what was found was limited to that sample or similar individuals and not generalizable to everyone else.

Scientific Methods

The particular method used to conduct research may vary by discipline and since lifespan development is multidisciplinary, more than one method may be used to study human development. One method of scientific investigation involves the following steps:

Determining a research question
Reviewing previous studies addressing the topic in question (known as a literature review)
Determining a method of gathering information
Conducting the study
Interpreting the results
Drawing conclusions; stating limitations of the study and suggestions for future research
Making the findings available to others (both to share information and to have the work scrutinized by others)

The findings of these scientific studies can then be used by others as they explore the area of interest. Through this process, a literature or knowledge base is established. This model of scientific investigation presents research as a linear process guided by a specific research question. And it typically involves quantitative research , which relies on numerical data or using statistics to understand and report what has been studied.

Another model of research, referred to as qualitative research, may involve steps such as these:

Begin with a broad area of interest and a research question
Gain entrance into a group to be researched
Gather field notes about the setting, the people, the structure, the activities or other areas of interest
Ask open-ended, broad “grand tour” types of questions when interviewing subjects
Modify research questions as the study continues
Note patterns or consistencies
Explore new areas deemed important by the people being observed
Report findings

In this type of research, theoretical ideas are “grounded” in the experiences of the participants. The researcher is the student and the people in the setting are the teachers as they inform the researcher of their world (Glazer & Strauss, 1967). Researchers should be aware of their own biases and assumptions, acknowledge them and bracket them in efforts to keep them from limiting accuracy in reporting. Sometimes qualitative studies are used initially to explore a topic and more quantitative studies are used to test or explain what was first described.

A good way to become more familiar with these scientific research methods, both quantitative and qualitative, is to look at journal articles, which are written in sections that follow these steps in the scientific process. Most psychological articles and many papers in the social sciences follow the writing guidelines and format dictated by the American Psychological Association (APA) (https://owl.english.purdue.edu/owl/section/2/10/) . In general, the structure follows: abstract (summary of the article), introduction or literature review, methods explaining how the study was conducted, results of the study, discussion and interpretation of findings, and references.

Link to Learning

Brené Brown is a bestselling author and social work professor at the University of Houston. She conducts grounded theory research by collecting qualitative data from large numbers of participants. In Brené Brown’s TED Talk The Power of Vulnerability , (https://www.youtube.com/watch?time_continue=177&v=iCvmsMzlF7o) Brown refers to herself as a storyteller-researcher as she explains her research process and summarizes her results.

Research Methods and Objectives

The main categories of psychological research are descriptive, correlational, and experimental research. Research studies that do not test specific relationships between variables are called descriptive, or qualitative, studies . These studies are used to describe general or specific behaviors and attributes that are observed and measured. In the early stages of research it might be difficult to form a hypothesis, especially when there is not any existing literature in the area. In these situations designing an experiment would be premature, as the question of interest is not yet clearly defined as a hypothesis. Often a researcher will begin with a non-experimental approach, such as a descriptive study, to gather more information about the topic before designing an experiment or correlational study to address a specific hypothesis. Some examples of descriptive questions include:

“How much time do parents spend with children?”
“How many times per week do couples have intercourse?”
“When is marital satisfaction greatest?”

The main types of descriptive studies include observation, case studies, surveys, and content analysis (which we’ll examine further in the module). Descriptive research is distinct from correlational research , in which psychologists formally test whether a relationship exists between two or more variables. Experimental research goes a step further beyond descriptive and correlational research and randomly assigns people to different conditions, using hypothesis testing to make inferences about how these conditions affect behavior. Some experimental research includes explanatory studies, which are efforts to answer the question “why” such as:

“Why have rates of divorce leveled off?”
“Why are teen pregnancy rates down?”
“Why has the average life expectancy increased?”

Evaluation research is designed to assess the effectiveness of policies or programs. For instance, research might be designed to study the effectiveness of safety programs implemented in schools for installing car seats or fitting bicycle helmets. Do children who have been exposed to the safety programs wear their helmets? Do parents use car seats properly? If not, why not?

This Crash Course video provides a brief overview of psychological research, which we’ll cover in more detail on the coming pages.

Research Methods

Types of Descriptive Research

Observation.

Case Studies

In this video, Harvard psychologist Dan Gilbert explains survey research that was conducted to explore the way our preferences change over time.

Content Analysis

U.S. Census Data is available and widely used to look at trends and changes taking place in the United States (visit the United States Census website (http://www.census.gov/) and check it out). There are also a number of other agencies that collect data on family life, sexuality, and on many other areas of interest in human development (go to the NORC at the University of Chicago website (http://www.norc.uchicago.edu/) or the Henry J Kaiser Family Foundation website (http://www.kff.org/) and see what you find).

Correlational and Experimental Research

Correlational research.

When scientists passively observe and measure phenomena it is called correlational research . Here, researchers do not intervene and change behavior, as they do in experiments. In correlational research, the goal is to identify patterns of relationships, but not cause and effect. Importantly, with correlational research, you can examine only two variables at a time, no more and no less.

So, what if you wanted to test whether spending money on others is related to happiness, but you don’t have $20 to give to each participant in order to have them spend it for your experiment? You could use a correlational design—which is exactly what Professor Elizabeth Dunn (2008) at the University of British Columbia did when she conducted research on spending and happiness. She asked people how much of their income they spent on others or donated to charity, and later she asked them how happy they were. Do you think these two variables were related? Yes, they were! The more money people reported spending on others, the happier they were.

Understanding Correlation

To find out how well two variables correlate, you can plot the relationship between the two scores on what is known as a scatterplot . In the scatterplot, each dot represents a data point. (In this case it’s individuals, but it could be some other unit.) Importantly, each dot provides us with two pieces of information—in this case, information about how good the person rated the past month (x-axis) and how happy the person felt in the past month (y-axis). Which variable is plotted on which axis does not matter.

Scatterplot of the association between happiness and ratings of the past month, a positive correlation (r = .81)

The association between two variables can be summarized statistically using the correlation coefficient (abbreviated as r). A correlation coefficient provides information about the direction and strength of the association between two variables. For the example above, the direction of the association is positive. This means that people who perceived the past month as being good reported feeling more happy, whereas people who perceived the month as being bad reported feeling less happy.

With a positive correlation , the two variables go up or down together. In a scatterplot, the dots form a pattern that extends from the bottom left to the upper right (just as they do in Figure 3). The r value for a positive correlation is indicated by a positive number (although, the positive sign is usually omitted). Here, the r value is .81.

A negative correlation is one in which the two variables move in opposite directions. That is, as one variable goes up, the other goes down. Figure 4 shows the association between the average height of males in a country (y-axis) and the pathogen prevalence (or commonness of disease; x-axis) of that country. In this scatterplot, each dot represents a country. Notice how the dots extend from the top left to the bottom right. What does this mean in real-world terms? It means that people are shorter in parts of the world where there is more disease. The r value for a negative correlation is indicated by a negative number—that is, it has a minus (–) sign in front of it. Here, it is –.83.

Scatterplot showing the association between average male height and pathogen prevalence, a negative correlation (r = –.83).

The strength of a correlation has to do with how well the two variables align. Recall that in Professor Dunn’s correlational study, spending on others positively correlated with happiness; the more money people reported spending on others, the happier they reported to be. At this point you may be thinking to yourself, I know a very generous person who gave away lots of money to other people but is miserable! Or maybe you know of a very stingy person who is happy as can be. Yes, there might be exceptions. If an association has many exceptions, it is considered a weak correlation. If an association has few or no exceptions, it is considered a strong correlation. A strong correlation is one in which the two variables always, or almost always, go together. In the example of happiness and how good the month has been, the association is strong. The stronger a correlation is, the tighter the dots in the scatterplot will be arranged along a sloped line.

The r value of a strong correlation will have a high absolute value (a perfect correlation has an absolute value of the whole number one, or 1.00). In other words, you disregard whether there is a negative sign in front of the r value, and just consider the size of the numerical value itself. If the absolute value is large, it is a strong correlation. A weak correlation is one in which the two variables correspond some of the time, but not most of the time. Figure 5 shows the relation between valuing happiness and grade point average (GPA). People who valued happiness more tended to earn slightly lower grades, but there were lots of exceptions to this. The r value for a weak correlation will have a low absolute value. If two variables are so weakly related as to be unrelated, we say they are uncorrelated, and the r value will be zero or very close to zero. In the previous example, is the correlation between height and pathogen prevalence strong? Compared to Figure 5, the dots in Figure 4 are tighter and less dispersed. The absolute value of –.83 is large (closer to one than to zero). Therefore, it is a strong negative correlation.

Scatterplot showing the association between valuing happiness and GPA, a weak negative correlation (r = –.32).

Problems with correlation

If generosity and happiness are positively correlated, should we conclude that being generous causes happiness? Similarly, if height and pathogen prevalence are negatively correlated, should we conclude that disease causes shortness? From a correlation alone, we can’t be certain. For example, in the first case, it may be that happiness causes generosity, or that generosity causes happiness. Or, a third variable might cause both happiness and generosity, creating the illusion of a direct link between the two. For example, wealth could be the third variable that causes both greater happiness and greater generosity. This is why correlation does not mean causation—an often repeated phrase among psychologists.

In this video, University of Pennsylvania psychologist and bestselling author, Angela Duckworth describes the correlational research that informed her understanding of grit.

Click through this interactive presentation to examine actual research studies.

https://h5p.org/h5p/embed/566660

Experimental Research

Experiments are designed to test hypotheses (or specific statements about the relationship between variables ) in a controlled setting in efforts to explain how certain factors or events produce outcomes. A variable is anything that changes in value. Concepts are operationalized or transformed into variables in research which means that the researcher must specify exactly what is going to be measured in the study. For example, if we are interested in studying marital satisfaction, we have to specify what marital satisfaction really means or what we are going to use as an indicator of marital satisfaction. What is something measurable that would indicate some level of marital satisfaction? Would it be the amount of time couples spend together each day? Or eye contact during a discussion about money? Or maybe a subject’s score on a marital satisfaction scale? Each of these is measurable but these may not be equally valid or accurate indicators of marital satisfaction. What do you think? These are the kinds of considerations researchers must make when working through the design.

The experimental method is the only research method that can measure cause and effect relationships between variables. Three conditions must be met in order to establish cause and effect. Experimental designs are useful in meeting these conditions:

The independent and dependent variables must be related. In other words, when one is altered, the other changes in response. The independent variable is something altered or introduced by the researcher; sometimes thought of as the treatment or intervention. The dependent variable is the outcome or the factor affected by the introduction of the independent variable; the dependent variable depends on the independent variable. For example, if we are looking at the impact of exercise on stress levels, the independent variable would be exercise; the dependent variable would be stress.
The cause must come before the effect. Experiments measure subjects on the dependent variable before exposing them to the independent variable (establishing a baseline). So we would measure the subjects’ level of stress before introducing exercise and then again after the exercise to see if there has been a change in stress levels. (Observational and survey research does not always allow us to look at the timing of these events which makes understanding causality problematic with these methods.)
The cause must be isolated. The researcher must ensure that no outside, perhaps unknown variables, are actually causing the effect we see. The experimental design helps make this possible. In an experiment, we would make sure that our subjects’ diets were held constant throughout the exercise program. Otherwise, the diet might really be creating a change in stress level rather than exercise.

A basic experimental design involves beginning with a sample (or subset of a population) and randomly assigning subjects to one of two groups: the experimental group or the control group . Ideally, to prevent bias, the participants would be blind to their condition (not aware of which group they are in) and the researchers would also be blind to each participant’s condition (referred to as “ double blind “). The experimental group is the group that is going to be exposed to an independent variable or condition the researcher is introducing as a potential cause of an event. The control group is going to be used for comparison and is going to have the same experience as the experimental group but will not be exposed to the independent variable. This helps address the placebo effect, which is that a group may expect changes to happen just by participating. After exposing the experimental group to the independent variable, the two groups are measured again to see if a change has occurred. If so, we are in a better position to suggest that the independent variable caused the change in the dependent variable . The basic experimental model looks like this:

The major advantage of the experimental design is that of helping to establish cause and effect relationships. A disadvantage of this design is the difficulty of translating much of what concerns us about human behavior into a laboratory setting.

Have you ever wondered why people make decisions that seem to be in opposition to their longterm best interest? In Eldar Shafir’s TED Talk Living Under Scarcity (https://www.youtube.com/watch?time_continue=18&v=gV1ESN8NGh8) , Shafir describes a series of experiments that shed light on how scarcity (real or perceived) affects our decisions.

Developmental Research Designs

Now you know about some tools used to conduct research about human development. Remember, research methods are tools that are used to collect information. But it is easy to confuse research methods and research design. Research design is the strategy or blueprint for deciding how to collect and analyze information. Research design dictates which methods are used and how. Developmental research designs are techniques used particularly in lifespan development research. When we are trying to describe development and change, the research designs become especially important because we are interested in what changes and what stays the same with age. These techniques try to examine how age, cohort, gender, and social class impact development.

Cross-sectional designs

The majority of developmental studies use cross-sectional designs because they are less time-consuming and less expensive than other developmental designs. Cross-sectional research designs are used to examine behavior in participants of different ages who are tested at the same point in time. Let’s suppose that researchers are interested in the relationship between intelligence and aging. They might have a hypothesis (an educated guess, based on theory or observations) that intelligence declines as people get older. The researchers might choose to give a certain intelligence test to individuals who are 20 years old, individuals who are 50 years old, and individuals who are 80 years old at the same time and compare the data from each age group. This research is cross-sectional in design because the researchers plan to examine the intelligence scores of individuals of different ages within the same study at the same time; they are taking a “cross-section” of people at one point in time. Let’s say that the comparisons find that the 80-year-old adults score lower on the intelligence test than the 50-year-old adults, and the 50-year-old adults score lower on the intelligence test than the 20-year-old adults. Based on these data, the researchers might conclude that individuals become less intelligent as they get older. Would that be a valid (accurate) interpretation of the results?

Text stating that the year of study is 2010 and an experiment looks at cohort A with 20 year olds, cohort B of 50 year olds and cohort C with 80 year olds

No, that would not be a valid conclusion because the researchers did not follow individuals as they aged from 20 to 50 to 80 years old. One of the primary limitations of cross-sectional research is that the results yield information about age differences not necessarily changes with age or over time. That is, although the study described above can show that in 2010, the 80-year-olds scored lower on the intelligence test than the 50-year-olds, and the 50-year-olds scored lower on the intelligence test than the 20-year-olds, the data used to come up with this conclusion were collected from different individuals (or groups of individuals). It could be, for instance, that when these 20-year-olds get older (50 and eventually 80), they will still score just as high on the intelligence test as they did at age 20. In a similar way, maybe the 80-year-olds would have scored relatively low on the intelligence test even at ages 50 and 20; the researchers don’t know for certain because they did not follow the same individuals as they got older.

It is also possible that the differences found between the age groups are not due to age, per se, but due to cohort effects. The 80-year-olds in this 2010 research grew up during a particular time and experienced certain events as a group. They were born in 1930 and are part of the Traditional or Silent Generation. The 50-year-olds were born in 1960 and are members of the Baby Boomer cohort. The 20-year-olds were born in 1990 and are part of the Millennial or Gen Y Generation. What kinds of things did each of these cohorts experience that the others did not experience or at least not in the same ways?

You may have come up with many differences between these cohorts’ experiences, such as living through certain wars, political and social movements, economic conditions, advances in technology, changes in health and nutrition standards, etc. There may be particular cohort differences that could especially influence their performance on intelligence tests, such as education level and use of computers. That is, many of those born in 1930 probably did not complete high school; those born in 1960 may have high school degrees, on average, but the majority did not attain college degrees; the young adults are probably current college students. And this is not even considering additional factors such as gender, race, or socioeconomic status. The young adults are used to taking tests on computers, but the members of the other two cohorts did not grow up with computers and may not be as comfortable if the intelligence test is administered on computers. These factors could have been a factor in the research results.

Another disadvantage of cross-sectional research is that it is limited to one time of measurement. Data are collected at one point in time and it’s possible that something could have happened in that year in history that affected all of the participants, although possibly each cohort may have been affected differently. Just think about the mindsets of participants in research that was conducted in the United States right after the terrorist attacks on September 11, 2001.

Longitudinal research designs

Middle aged woman holding own photograph of her younger self.

Longitudinal research involves beginning with a group of people who may be of the same age and background (cohort) and measuring them repeatedly over a long period of time. One of the benefits of this type of research is that people can be followed through time and be compared with themselves when they were younger; therefore changes with age over time are measured. What would be the advantages and disadvantages of longitudinal research? Problems with this type of research include being expensive, taking a long time, and subjects dropping out over time. Think about the film, 63 Up , part of the Up Series mentioned earlier, which is an example of following individuals over time. In the videos, filmed every seven years, you see how people change physically, emotionally, and socially through time; and some remain the same in certain ways, too. But many of the participants really disliked being part of the project and repeatedly threatened to quit; one disappeared for several years; another died before her 63rd year. Would you want to be interviewed every seven years? Would you want to have it made public for all to watch?

Longitudinal research designs are used to examine behavior in the same individuals over time. For instance, with our example of studying intelligence and aging, a researcher might conduct a longitudinal study to examine whether 20-year-olds become less intelligent with age over time. To this end, a researcher might give an intelligence test to individuals when they are 20 years old, again when they are 50 years old, and then again when they are 80 years old. This study is longitudinal in nature because the researcher plans to study the same individuals as they age. Based on these data, the pattern of intelligence and age might look different than from the cross-sectional research; it might be found that participants’ intelligence scores are higher at age 50 than at age 20 and then remain stable or decline a little by age 80. How can that be when cross-sectional research revealed declines in intelligence with age?

The same person, "Person A" is 20 years old in 2010, 50 years old in 2040, and 80 in 2070.

Since longitudinal research happens over a period of time (which could be short term, as in months, but is often longer, as in years), there is a risk of attrition. Attrition occurs when participants fail to complete all portions of a study. Participants may move, change their phone numbers, die, or simply become disinterested in participating over time. Researchers should account for the possibility of attrition by enrolling a larger sample into their study initially, as some participants will likely drop out over time. There is also something known as selective attrition— this means that certain groups of individuals may tend to drop out. It is often the least healthy, least educated, and lower socioeconomic participants who tend to drop out over time. That means that the remaining participants may no longer be representative of the whole population, as they are, in general, healthier, better educated, and have more money. This could be a factor in why our hypothetical research found a more optimistic picture of intelligence and aging as the years went by. What can researchers do about selective attrition? At each time of testing, they could randomly recruit more participants from the same cohort as the original members, to replace those who have dropped out.

The results from longitudinal studies may also be impacted by repeated assessments. Consider how well you would do on a math test if you were given the exact same exam every day for a week. Your performance would likely improve over time, not necessarily because you developed better math abilities, but because you were continuously practicing the same math problems. This phenomenon is known as a practice effect. Practice effects occur when participants become better at a task over time because they have done it again and again (not due to natural psychological development). So our participants may have become familiar with the intelligence test each time (and with the computerized testing administration).

Another limitation of longitudinal research is that the data are limited to only one cohort. As an example, think about how comfortable the participants in the 2010 cohort of 20-year-olds are with computers. Since only one cohort is being studied, there is no way to know if findings would be different from other cohorts. In addition, changes that are found as individuals age over time could be due to age or to time of measurement effects. That is, the participants are tested at different periods in history, so the variables of age and time of measurement could be confounded (mixed up). For example, what if there is a major shift in workplace training and education between 2020 and 2040 and many of the participants experience a lot more formal education in adulthood, which positively impacts their intelligence scores in 2040? Researchers wouldn’t know if the intelligence scores increased due to growing older or due to a more educated workforce over time between measurements.

Sequential research designs

Sequential research designs include elements of both longitudinal and cross-sectional research designs. Similar to longitudinal designs, sequential research features participants who are followed over time; similar to cross-sectional designs, sequential research includes participants of different ages. This research design is also distinct from those that have been discussed previously in that individuals of different ages are enrolled into a study at various points in time to examine age-related changes, development within the same individuals as they age, and to account for the possibility of cohort and/or time of measurement effects. In 1965, K. Warner Schaie [1] (a leading theorist and researcher on intelligence and aging), described particular sequential designs: cross-sequential, cohort sequential, and time-sequential. The differences between them depended on which variables were focused on for analyses of the data (data could be viewed in terms of multiple cross-sectional designs or multiple longitudinal designs or multiple cohort designs). Ideally, by comparing results from the different types of analyses, the effects of age, cohort, and time in history could be separated out.

Consider, once again, our example of intelligence and aging. In a study with a sequential design, a researcher might recruit three separate groups of participants (Groups A, B, and C). Group A would be recruited when they are 20 years old in 2010 and would be tested again when they are 50 and 80 years old in 2040 and 2070, respectively (similar in design to the longitudinal study described previously). Group B would be recruited when they are 20 years old in 2040 and would be tested again when they are 50 years old in 2070. Group C would be recruited when they are 20 years old in 2070 and so on.

Shows cohorts A, B, and C. Cohort A tests age 20 in 2010, age 50 in 2040, and age 80 in 2070. Cohort B begins in 2040 and tests new 20 year-olds so they can be compared with the 50 year olds from cohort A. Cohort C tests 20 year olds in 2070, who are compared with 20 year olds from cohorts B and A, but also with the original groups of 20-year olds who are now age 80 (cohort A) and age 50 (cohort B).

Studies with sequential designs are powerful because they allow for both longitudinal and cross-sectional comparisons—changes and/or stability with age over time can be measured and compared with differences between age and cohort groups. This research design also allows for the examination of cohort and time of measurement effects. For example, the researcher could examine the intelligence scores of 20-year-olds in different times in history and different cohorts (follow the yellow diagonal lines in figure 3). This might be examined by researchers who are interested in sociocultural and historical changes (because we know that lifespan development is multidisciplinary). One way of looking at the usefulness of the various developmental research designs was described by Schaie and Baltes (1975) [2] : cross-sectional and longitudinal designs might reveal change patterns while sequential designs might identify developmental origins for the observed change patterns.

Since they include elements of longitudinal and cross-sectional designs, sequential research has many of the same strengths and limitations as these other approaches. For example, sequential work may require less time and effort than longitudinal research (if data are collected more frequently than over the 30-year spans in our example) but more time and effort than cross-sectional research. Although practice effects may be an issue if participants are asked to complete the same tasks or assessments over time, attrition may be less problematic than what is commonly experienced in longitudinal research since participants may not have to remain involved in the study for such a long period of time.

When considering the best research design to use in their research, scientists think about their main research question and the best way to come up with an answer. A table of advantages and disadvantages for each of the described research designs is provided here to help you as you consider what sorts of studies would be best conducted using each of these different approaches.

Challenges Conducting Developmental Research

Challenges associated with conducting developmental research.

The previous sections describe research tools to assess development across the lifespan, as well as the ways that research designs can be used to track age-related changes and development over time. Before you begin conducting developmental research, however, you must also be aware that testing individuals of certain ages (such as infants and children) or making comparisons across ages (such as children compared to teens) comes with its own unique set of challenges. In the final section of this module, let’s look at some of the main issues that are encountered when conducting developmental research, namely ethical concerns, recruitment issues, and participant attrition.

Ethical Concerns

As a student of the social sciences, you may already know that Institutional Review Boards (IRBs) must review and approve all research projects that are conducted at universities, hospitals, and other institutions (each broad discipline or field, such as psychology or social work, often has its own code of ethics that must also be followed, regardless of institutional affiliation). An IRB is typically a panel of experts who read and evaluate proposals for research. IRB members want to ensure that the proposed research will be carried out ethically and that the potential benefits of the research outweigh the risks and potential harm (psychological as well as physical harm) for participants.

What you may not know though, is that the IRB considers some groups of participants to be more vulnerable or at-risk than others. Whereas university students are generally not viewed as vulnerable or at-risk, infants and young children commonly fall into this category. What makes infants and young children more vulnerable during research than young adults? One reason infants and young children are perceived as being at increased risk is due to their limited cognitive capabilities, which makes them unable to state their willingness to participate in research or tell researchers when they would like to drop out of a study. For these reasons, infants and young children require special accommodations as they participate in the research process. Similar issues and accommodations would apply to adults who are deemed to be of limited cognitive capabilities.

When thinking about special accommodations in developmental research, consider the informed consent process. If you have ever participated in scientific research, you may know through your own experience that adults commonly sign an informed consent statement (a contract stating that they agree to participate in research) after learning about a study. As part of this process, participants are informed of the procedures to be used in the research, along with any expected risks or benefits. Infants and young children cannot verbally indicate their willingness to participate, much less understand the balance of potential risks and benefits. As such, researchers are oftentimes required to obtain written informed consent from the parent or legal guardian of the child participant, an adult who is almost always present as the study is conducted. In fact, children are not asked to indicate whether they would like to be involved in a study at all (a process known as assent) until they are approximately seven years old. Because infants and young children cannot easily indicate if they would like to discontinue their participation in a study, researchers must be sensitive to changes in the state of the participant (determining whether a child is too tired or upset to continue) as well as to parent desires (in some cases, parents might want to discontinue their involvement in the research). As in adult studies, researchers must always strive to protect the rights and well-being of the minor participants and their parents when conducting developmental research.

This video from the US Department of Health and Human Services provides an overview of the Institutional Review Board process.

Recruitment

An additional challenge in developmental science is participant recruitment. Recruiting university students to participate in adult studies is typically easy. Many colleges and universities offer extra credit for participation in research and have locations such as bulletin boards and school newspapers where research can be advertised. Unfortunately, young children cannot be recruited by making announcements in Introduction to Psychology courses, by posting ads on campuses, or through online platforms such as Amazon Mechanical Turk. Given these limitations, how do researchers go about finding infants and young children to be in their studies?

The answer to this question varies along multiple dimensions. Researchers must consider the number of participants they need and the financial resources available to them, among other things. Location may also be an important consideration. Researchers who need large numbers of infants and children may attempt to recruit them by obtaining infant birth records from the state, county, or province in which they reside. Some areas make this information publicly available for free, whereas birth records must be purchased in other areas (and in some locations birth records may be entirely unavailable as a recruitment tool). If birth records are available, researchers can use the obtained information to call families by phone or mail them letters describing possible research opportunities. All is not lost if this recruitment strategy is unavailable, however. Researchers can choose to pay a recruitment agency to contact and recruit families for them. Although these methods tend to be quick and effective, they can also be quite expensive. More economical recruitment options include posting advertisements and fliers in locations frequented by families, such as mommy-and-me classes, local malls, and preschools or daycare centers. Researchers can also utilize online social media outlets like Facebook, which allows users to post recruitment advertisements for a small fee. Of course, each of these different recruitment techniques requires IRB approval. And if children are recruited and/or tested in school settings, permission would need to be obtained ahead of time from teachers, schools, and school districts (as well as informed consent from parents or guardians).

And what about the recruitment of adults? While it is easy to recruit young college students to participate in research, some would argue that it is too easy and that college students are samples of convenience. They are not randomly selected from the wider population, and they may not represent all young adults in our society (this was particularly true in the past with certain cohorts, as college students tended to be mainly white males of high socioeconomic status). In fact, in the early research on aging, this type of convenience sample was compared with another type of convenience sample—young college students tended to be compared with residents of nursing homes! Fortunately, it didn’t take long for researchers to realize that older adults in nursing homes are not representative of the older population; they tend to be the oldest and sickest (physically and/or psychologically). Those initial studies probably painted an overly negative view of aging, as young adults in college were being compared to older adults who were not healthy, had not been in school nor taken tests in many decades, and probably did not graduate high school, let alone college. As we can see, recruitment and random sampling can be significant issues in research with adults, as well as infants and children. For instance, how and where would you recruit middle-aged adults to participate in your research?

A tired looking mother closes her eyes and rubs her forehead as her baby cries.

Another important consideration when conducting research with infants and young children is attrition . Although attrition is quite common in longitudinal research in particular (see the previous section on longitudinal designs for an example of high attrition rates and selective attrition in lifespan developmental research), it is also problematic in developmental science more generally, as studies with infants and young children tend to have higher attrition rates than studies with adults. For example, high attrition rates in ERP (event-related potential, which is a technique to understand brain function) studies oftentimes result from the demands of the task: infants are required to sit still and have a tight, wet cap placed on their heads before watching still photographs on a computer screen in a dark, quiet room. In other cases, attrition may be due to motivation (or a lack thereof). Whereas adults may be motivated to participate in research in order to receive money or extra course credit, infants and young children are not as easily enticed. In addition, infants and young children are more likely to tire easily, become fussy, and lose interest in the study procedures than are adults. For these reasons, research studies should be designed to be as short as possible – it is likely better to break up a large study into multiple short sessions rather than cram all of the tasks into one long visit to the lab. Researchers should also allow time for breaks in their study protocols so that infants can rest or have snacks as needed. Happy, comfortable participants provide the best data.

Conclusions

Lifespan development is a fascinating field of study – but care must be taken to ensure that researchers use appropriate methods to examine human behavior, use the correct experimental design to answer their questions, and be aware of the special challenges that are part-and-parcel of developmental research. After reading this module, you should have a solid understanding of these various issues and be ready to think more critically about research questions that interest you. For example, what types of questions do you have about lifespan development? What types of research would you like to conduct? Many interesting questions remain to be examined by future generations of developmental scientists – maybe you will make one of the next big discoveries!

attrition: reduction in the number of research participants as some drop out over time case study: exploring a single case or situation in great detail. Information may be gathered with the use of observation, interviews, testing, or other methods to uncover as much as possible about a person or situation content analysis: involves looking at media such as old texts, pictures, commercials, lyrics or other materials to explore patterns or themes in culture control group: a comparison group that is equivalent to the experimental group, but is not given the independent variable correlation: the relationship between two or more variables; when two variables are correlated, one variable changes as the other does correlational research: research design with the goal of identifying patterns of relationships, but not cause and effect correlation coefficient: number from -1 to +1, indicating the strength and direction of the relationship between variables, and usually represented by r cross-sectional research: used to examine behavior in participants of different ages who are tested at the same point in time; may confound age and cohort differences dependent variable: the outcome or variable that is supposedly affected by the independent variable descriptive studies: research focused on describing an occurrence double-blind: a research design in which neither the participants nor the researchers know whether an individual is assigned to the experimental group or the control group evaluation research: research designed to assess the effectiveness of policies or programs experimental group: the group of participants in an experiment who receive the independent variable experiments: designed to test hypotheses in a controlled setting in efforts to explain how certain factors or events produce outcomes; the only research method that measures cause and effect relationships between variables experimental research: research that involves randomly assigning people to different conditions and using hypothesis testing to make inferences about how these conditions affect behavior; the only method that measures cause and effect between variables explanatory studies: research that tries to answer the question “why” Hawthorne effect: individuals tend to change their behavior when they know they are being watched hypotheses: specific statements or predictions about the relationship between variables independent variable: something that is manipulated or introduced by the researcher to the experimental group; treatment or intervention informed consent: a process of informing a research participant what to expect during a study, any risks involved, and the implications of the research, and then obtaining the person’s agreement to participate Institutional Review Boards (IRBs): a panel of experts who review research proposals for any research to be conducted in association with the institution (for example, a university) longitudinal research: studying a group of people who may be of the same age and background (cohort), and measuring them repeatedly over a long period of time; may confound age and time of measurement effects negative correlation: two variables change in different directions, with one becoming larger as the other becomes smaller; a negative correlation is not the same thing as no correlation observational studies: also called naturalistic observation, involves watching and recording the actions of participants operationalized: concepts transformed into variables that can be measured in research positive correlation: two variables change in the same direction, both becoming either larger or smaller qualitative research: theoretical ideas are “grounded” in the experiences of the participants, who answer open-ended questions quantitative research: involves numerical data that are quantified using statistics to understand and report what has been studied reliability: when something yields consistent results research design: the strategy or blueprint for deciding how to collect and analyze information; dictates which methods are used and how scatterplot: a plot or mathematical diagram consisting of data points that represent two variables secondary content analysis: archival research, involves analyzing information that has already been collected or examining documents or media to uncover attitudes, practices or preferences selective attrition: certain groups of individuals may tend to drop out more frequently resulting in the remaining participants longer being representative of the whole population

Schaie, K.W. (1965). A general model for the study of developmental problems. Psychological Bulletin, 64(2), 92-107. ↵
Schaie, K.W. & Baltes, B.P. (1975). On sequential strategies in developmental research: Description or Explanation. Human Development, 18: 384-390. ↵

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Cognitive Development
Continuous Development
Developmental Milestones
Discontinuous Development
Normative Approach
Physical Development
Psychosocial Development

What Is Lifespan Development?

Define and distinguish between the three domains of development: physical, cognitive and psychosocial
Discuss the normative approach to development
Understand the three major issues in development: continuity and discontinuity, one common course of development or many unique courses of development, and nature versus nurture

My heart leaps up when I behold A rainbow in the sky: So was it when my life began; So is it now I am a man; So be it when I shall grow old, Or let me die! The Child is father of the Man; I could wish my days to be Bound each to each by natural piety. (Wordsworth, 1802)

Research Methods in Developmental Psychology

Across these three domains—physical, cognitive, and psychosocial—the normative approach to development is also discussed. This approach asks, “What is normal development?” In the early decades of the 20th century, normative psychologists studied large numbers of children at various ages to determine norms (i.e., average ages) of when most children reach specific developmental milestones in each of the three domains (Gesell, 1933, 1939, 1940; Gesell & Ilg, 1946; Hall, 1904). Although children develop at slightly different rates, we can use these age-related averages as general guidelines to compare children with same-age peers to determine the approximate ages they should reach specific normative events called developmental milestones (e.g., crawling, walking, writing, dressing, naming colors, speaking in sentences, and starting puberty).

Not all normative events are universal, meaning they are not experienced by all individuals across all cultures. Biological milestones, such as puberty, tend to be universal, but social milestones, such as the age when children begin formal schooling, are not necessarily universal; instead, they affect most individuals in a particular culture (Gesell & Ilg, 1946). For example, in developed countries children begin school around 5 or 6 years old, but in developing countries, like Nigeria, children often enter school at an advanced age, if at all (Huebler, 2005; United Nations Educational, Scientific, and Cultural Organization [UNESCO], 2013).

The Centers for Disease Control and Prevention (CDC) describes the developmental milestones for children from 2 months through 5 years old. After reviewing the information, take this quiz to see how well you recall what you’ve learned. If you are a parent with concerns about your child’s development, contact your pediatrician.

ISSUES IN DEVELOPMENTAL PSYCHOLOGY

Is Development Continuous or Discontinuous?

Continuous development views development as a cumulative process, gradually improving on existing skills ( Figure ). With this type of development, there is gradual change. Consider, for example, a child’s physical growth: adding inches to her height year by year. In contrast, theorists who view development as discontinuous believe that development takes place in unique stages: It occurs at specific times or ages. With this type of development, the change is more sudden, such as an infant’s ability to conceive object permanence.

Is There One Course of Development or Many?

For instance, let’s look at the Aché society in Paraguay. They spend a significant amount of time foraging in forests. While foraging, Aché mothers carry their young children, rarely putting them down in order to protect them from getting hurt in the forest. Consequently, their children walk much later: They walk around 23–25 months old, in comparison to infants in Western cultures who begin to walk around 12 months old. However, as Aché children become older, they are allowed more freedom to move about, and by about age 9, their motor skills surpass those of U.S. children of the same age: Aché children are able to climb trees up to 25 feet tall and use machetes to chop their way through the forest (Kaplan & Dove, 1987). As you can see, our development is influenced by multiple contexts, so the timing of basic motor functions may vary across cultures. However, the functions themselves are present in all societies ( Figure ).

How Do Nature and Nurture Influence Development?

Are we who we are because of nature (biology and genetics), or are we who we are because of nurture (our environment and culture)? This longstanding question is known in psychology as the nature versus nurture debate. It seeks to understand how our personalities and traits are the product of our genetic makeup and biological factors, and how they are shaped by our environment, including our parents, peers, and culture. For instance, why do biological children sometimes act like their parents—is it because of genetics or because of early childhood environment and what the child has learned from the parents? What about children who are adopted—are they more like their biological families or more like their adoptive families? And how can siblings from the same family be so different?

We are all born with specific genetic traits inherited from our parents, such as eye color, height, and certain personality traits. Beyond our basic genotype, however, there is a deep interaction between our genes and our environment: Our unique experiences in our environment influence whether and how particular traits are expressed, and at the same time, our genes influence how we interact with our environment (Diamond, 2009; Lobo, 2008). This chapter will show that there is a reciprocal interaction between nature and nurture as they both shape who we become, but the debate continues as to the relative contributions of each.

The Achievement Gap: How Does Socioeconomic Status Affect Development?

The achievement gap refers to the persistent difference in grades, test scores, and graduation rates that exist among students of different ethnicities, races, and—in certain subjects—sexes (Winerman, 2011). Research suggests that these achievement gaps are strongly influenced by differences in socioeconomic factors that exist among the families of these children. While the researchers acknowledge that programs aimed at reducing such socioeconomic discrepancies would likely aid in equalizing the aptitude and performance of children from different backgrounds, they recognize that such large-scale interventions would be difficult to achieve. Therefore, it is recommended that programs aimed at fostering aptitude and achievement among disadvantaged children may be the best option for dealing with issues related to academic achievement gaps (Duncan & Magnuson, 2005).

Psychologists Betty Hart and Todd Risley (2006) spent their careers looking at early language ability and progression of children in various income levels. In one longitudinal study, they found that although all the parents in the study engaged and interacted with their children, middle- and high-income parents interacted with their children differently than low-income parents. After analyzing 1,300 hours of parent-child interactions, the researchers found that middle- and high-income parents talk to their children significantly more, starting when the children are infants. By 3 years old, high-income children knew almost double the number of words known by their low-income counterparts, and they had heard an estimated total of 30 million more words than the low-income counterparts (Hart & Risley, 2003). And the gaps only become more pronounced. Before entering kindergarten, high-income children score 60% higher on achievement tests than their low-income peers (Lee & Burkam, 2002).

There are solutions to this problem. At the University of Chicago, experts are working with low-income families, visiting them at their homes, and encouraging them to speak more to their children on a daily and hourly basis. Other experts are designing preschools in which students from diverse economic backgrounds are placed in the same classroom. In this research, low-income children made significant gains in their language development, likely as a result of attending the specialized preschool (Schechter & Byeb, 2007). What other methods or interventions could be used to decrease the achievement gap? What types of activities could be implemented to help the children of your community or a neighboring community?

Review Questions

The view that development is a cumulative process, gradually adding to the same type of skills is known as ________.

continuous development
discontinuous development

Developmental psychologists study human growth and development across three domains. Which of the following is not one of these domains?

psychological
psychosocial

How is lifespan development defined?

The study of how we grow and change from conception to death.
The study of how we grow and change in infancy and childhood.
The study of physical, cognitive, and psychosocial growth in children.
The study of emotions, personality, and social relationships.

Critical Thinking Questions

Describe the nature versus nurture controversy, and give an example of a trait and how it might be influenced by each?

Compare and contrast continuous and discontinuous development.

Why should developmental milestones only be used as a general guideline for normal child development?

Personal Application Questions

How are you different today from the person you were at 6 years old? What about at 16 years old? How are you the same as the person you were at those ages?

Your 3-year-old daughter is not yet potty trained. Based on what you know about the normative approach, should you be concerned? Why or why not?

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Case Studies in Lifespan Development 1st edition
Lifespan Development Case Study Presentation by Tori McCormick
The Basics of Lifespan Development: An Introduction
Module 1 Lifespan Development
D1.2 Theoretical Perspectives in Lifespan Development
Lifespan Development Diagram

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COMMENTS

Case Studies in Lifespan Development
Case Studies in Lifespan Development offers students a comprehensive view into life's key developmental stages through unique, diverse, and moving cases. Author Stephanie M. Wright presents a series of 12 case studies shaped by the contributions of real students—including their observations, concerns, and moments of triumph—to build immersive examples that readers can relate to and enjoy.
Case Studies in Lifespan Development
Case Studies in Lifespan Development offers students a comprehensive view into life's key developmental stages through unique, diverse, and moving cases. Author Stephanie M. Wright presents a series of 12 case studies shaped by the contributions of real students—including their observations, concerns, and moments of triumph—to build immersive examples that readers can relate to and enjoy.
9.1 What Is Lifespan Development?
In a case study, developmental psychologists collect a great deal of information from one individual in order to better understand physical and psychological changes over the lifespan. ... In one classic example of this research method being applied to a study of lifespan development Sigmund Freud analyzed the development of a child known as ...
Lifespan Development: A Psychological Perspective
Developmental Psychology, also known as Human Development or Lifespan Development, is the scientific study of ways in which people change, as well as stay the same, from conception to death. You will no doubt discover in the course of studying that the field examines change across a broad range of topics. These include physical and other psychophysiological processes, cognition, language, and ...
PDF Credit: TK
Through this case study and your lifespan course you will be asked to consider decisions . regarding Jamal's physical, emotional, and cognitive growth and development from several per- ... 1.4 Describe the methods and research designs used to study human development. Neka didn't expect to have a third son. In fact, she had been weighing how ...
Ch 3: Lifespan Development
In a case study, developmental psychologists collect a great deal of information from one individual in order to better understand physical and psychological changes over the lifespan. ... In one classic example of this research method being applied to a study of lifespan development Sigmund Freud analyzed the development of a child known as ...
Case Studies in Lifespan Development
There is a newer edition of this item: Lifespan Development: Lives in Context. $119.66. (12) Only 5 left in stock - order soon. Case Studies in Lifespan Development offers students a comprehensive view into life's key developmental stages through unique, diverse, and moving cases. Author Stephanie M. Wright presents a series of 12 case ...
Intro to Lifespan Development
People who study lifespan development approach it from different perspectives. Each perspective encompasses one or more theories—the broad, organized explanations and predictions concerning phenomena of interest. Theories of development provide a framework for thinking about human growth, development, and learning. ... (in this case, the ...
Case Studies in Lifespan Development
Case Studies in Lifespan Development offers students a comprehensive view into life's key developmental stages through unique, diverse, and moving cases. Author Stephanie M. Wright presents a series of 12 case studies shaped by the contributions of real students—including their observations, concerns, and moments of triumph—to build immersive examples that readers can relate to and enjoy.
What Is Lifespan Development?
In a case study, developmental psychologists collect a great deal of information from one individual in order to better understand physical and psychological changes over the lifespan. ... In one classic example of this research method being applied to a study of lifespan development Sigmund Freud analyzed the development of a child known as ...
3.8: Lecture: Introduction to Life Span, Growth and Development
Welcome to life span, growth and development. This is the study of how and why people change or remain the same over time. ... Case studies are a good way to explore unusual situations and can provide a basis for hypotheses that can be tested in other research. Confirmation bias can occur when clinicians trained to see a particular problem see ...
Case Studies in Lifespan Development
Case Studies in Lifespan Development offers students a comprehensive view into life's key developmental stages through unique, diverse, and moving cases. Author Stephanie M. Wright presents a series of 12 case studies shaped by the contributions of real students—including their observations, concerns, and moments of triumph—to build immersive examples that readers can relate to and enjoy.
PDF LIFE SPAN DEVELOPMENT
Standard Area: Life Span Development Content Standards: After concluding this unit, students understand: 1. Methods and issues in life span development 2. Theories of life span development 3. Prenatal development and the newborn 4. Infancy (i.e., the first 2 years of life) 5. Childhood 6. Adolescence 7. Adulthood and aging
Research Methods
Describe methods for collecting research data (including observation, survey, case study, content analysis, and secondary content analysis) We have just learned about some of the various models and objectives of research in lifespan development. Now we'll dig deeper to understand the methods and techniques used to describe, explain, or ...
Case Studies in Lifespan Development
Case Studies in Lifespan Development offers students a comprehensive view into life's key developmental stages through unique, diverse, and moving cases. Author Stephanie M. Wright presents a series of 12 case studies shaped by the contributions of real students—including their observations, concerns, and moments of triumph—to build immersive examples that readers can relate to and enjoy.
Case Studies in Lifespan Development
Case Studies in Lifespan Development offers students a comprehensive view into life's key developmental stages through unique, diverse, and moving cases. Author Stephanie M. Wright presents a series of 12 case studies shaped by the contributions of real students—including their observations, concerns, and moments of triumph—to build immersive examples that readers can relate to and enjoy.
Lifespan Developmental Research Methodologies
Case Study: All of the Above with Carefully Selected Participants or Settings. One of the best ways to gather in depth information about a person or group of people (e.g., a classroom, school, or neighborhood) is through a research methodology called the case study. Researchers focus on only one or a small number of target units, usually ...
Research in Lifespan Development
Research in Lifespan Development What you'll learn to do: examine how to do research in lifespan development. ... Case studies involve exploring a single case or situation in great detail. Information may be gathered with the use of observation, interviews, testing, or other methods to uncover as much as possible about a person or situation. ...
Case Studies in Lifespan Development 1st Edition
Over 7,000 institutions using Bookshelf across 241 countries. Case Studies in Lifespan Development 1st Edition is written by Stephanie M. Wright and published by SAGE Publications, Inc. The Digital and eTextbook ISBNs for Case Studies in Lifespan Development are 9781544367804, 1544367805 and the print ISBNs are 9781544361864, 1544361866.
Case Studies in Lifespan Development 1st Edition, Kindle Edition
Case Studies in Lifespan Development offers students a comprehensive view into life's key developmental stages through unique, diverse, and moving cases. Author Stephanie M. Wright presents a series of 12 case studies shaped by the contributions of real students—including their observations, concerns, and moments of triumph—to build immersive examples that readers can relate to and enjoy.
Final Case study
GSSC 1057 Lifespan Development Final Case Study. Lola Konjevic Tenzin Dhonden Anthony Adjei-Twum ADOLESENCE. 1. Camilla and Anthony are concerned that Alvin may start engaging in more sensation-seeking. behaviours in his adolescent years. Describe the rationale for Camilla and Anthony's concern. The rationale for Camilla and Anthony's ...
Lifespan Developmental Case Study: Sheridan College NURS10016
The Sheridan College. NURS10016: Human Growth and Development through the Lifespan. Kirti Kaila March 30th, 2021. Lifespan Developmental Case Study Raj is 40 years old, of Indian descent and is in the middle adulthood category which ranges from 30 years to late adulthood. This is a stage of generativity vs stagnation.
Sample Lifespan Review Project
M01 Chapter 1&2 Study Guide - Lifespan Development. Lifespan Development. Assignments. 100% (1) 6. M04 Chapter 7&8 Exam - Study Guide, Answer Key. Lifespan Development. Assignments. ... It is generally established in the age between 25 and 60 years, although as in the case of the rest of the stages of human development, it is not easy to ...
What Is Lifespan Development?
In a case study, developmental psychologists collect a great deal of information from one individual in order to better understand physical and psychological changes over the lifespan. ... In one classic example of this research method being applied to a study of lifespan development Sigmund Freud analyzed the development of a child known as ...