Developmental psychology the growth of mind and behavior

Developmental
Psychology



Developmental
Psychology
The Growth of Mind and Behavior

Frank Keil
YALE

B W.

UNIVERSITY

W. N O R T O N & C O M P A N Y

NEW YORK • LONDON


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Library of Congress Cataloging-in-Publication Data
Keil, Frank C., 1952–
Developmental psychology : the growth of mind and behavior / Frank Keil. — First edition.
pages cm
Includes bibliographical references and index.
ISBN 978-0-393-97885-8 (hardcover)
1. Developmental psychology. I. Title.
BF713.K443 2014

155—dc23
2013034957
W. W. Norton & Company, Inc., 500 Fifth Avenue, New York, NY 10110-0017
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About the Author
Frank C. Keil is the Charles C. and Dorathea S. Dilley Professor of Psychology and Linguistics
and chair of the Psychology Department at Yale University. Keil received his B.S. in Biology
from M.I.T. in 1973, an M.A. in Psychology from Stanford University in 1975, and a Ph.D. in
Psychology from the University of Pennsylvania in 1977. He was a faculty member at Cornell
University from 1977 to 1998 and has been at Yale since 1998. For over 35 years, he has taught
an undergraduate lecture course in developmental psychology, as well as advanced seminars at the
undergraduate and graduate level on topics in cognitive development and cognition.
Keil has published extensively on topics concerned with many areas of the development of
cognition and language. He wrote two books on aspects of conceptual development and, with
the philosopher Robert Wilson, he edited the MIT Encyclopedia of the Cognitive Sciences, which
was selected as the Outstanding Book in Psychology by the Association of American Publishers
in 1999. Keil served as president of the Society for Philosophy and Psychology and has received
numerous awards for his scholarship, including the Boyd R. McCandless Award (Developmental
Psychology), the Distinguished Scientific Award for an Early Career Contribution to Psychology,
a Guggenheim Fellowship, a fellowship at the Center for Advanced Study in the Behavioral
Sciences, a MERIT Award from the National Institutes of Health, and the Ann L. Brown
Award for Excellence in Developmental Research. Keil served as Master of Morse College at Yale
University from 2001 until 2012. Keil and his wife Kristi Lockhart, a clinical and developmental
psychologist, are parents of three sons who are now in their twenties and thirties.

Contents in Brief
PART I

Framing Psychological Development
Chapter 1 Approaching Psychological Development 2
Chapter 2 The Biology of Development 33

PART II

Origins
Chapter
Chapter
Chapter
Chapter
Chapter

PART III

8 Language Development 260
9 The Growth of Knowledge 303
10 The Growth of Cognitive Skills 343
11 Intelligence and Schooling 385

The Self and Others
Chapter
Chapter
Chapter
Chapter

PART V

Coming to Perceive the World 76
The Emergence of Action 115
Coming to Understand the Physical World 145
Connecting with the Social World 187
The Origins of Emotion, Temperament,
and Personality 227

Developing Competencies
Chapter
Chapter
Chapter
Chapter

PART IV

3
4
5
6
7

12
13
14
15

Morality in Thought and Action 426
Knowing Ourselves, Knowing Others 467
Becoming Part of the Family 503

Becoming Part of the Community 543

Broader Developmental Context
Chapter 16 Psychopathology in Childhood 586
Chapter 17 Development after Childhood and
Adolescence 629

vi


Contents
ABOUT THE AUTHOR v
PREFACE xvii

PART I Framing Psychological

Development
CHAPTER 1

Approaching Psychological
Development 2
Why Study Development? 4
Development as a Key to Understanding Children’s
Capabilities 4
Development as a Means for Insight into the Mature Form 5
Development and Social Policy 6

The Nature of Development 6
Categorizing Developmental Phenomena 7
Periods of Development

Areas of Development

Basic Questions about Psychological Development 9
Is Development Stage-like or Continuous?
Is Development Global or Local?
How Do Nature and Nurture Shape Development?

Perspectives on Development 14
Empiricist and Nativist Perspectives 14
Empiricism
Nativism

Comparative and Evolutionary Perspectives 17
Cross-Cultural Perspectives 18
Neuroscience Perspectives 19
Behaviorist Perspectives 19

Psychoanalytic Perspectives 20
Cognitive Science Perspectives 20

Studying Psychological Development 22
Observational Studies 22
Experimental Studies 23
Longitudinal Approaches 26
Cross-Sectional Approaches 27
Converging Methods 28
Designing a Sound Study 28
Reliability and Validity
Within-Subjects and Between-Subjects Designs

Conclusions 30
Summary 31

CHAPTER 2

The Biology of Development 33
The Basis of Development 35
Inputs to the Biological System 36
The Genes
The Environment
Interactions between Genes and Environment

Constraints on Development 38
Viability
Differentiation of Cells and Structures
Timing and Sequencing

vii


The Beginnings of Development 41

Brain Development 56

Meiosis and Fertilization 41

Major Changes to Brain Structures 57
Neurons and Neurotransmitters 58
Development of Neurons 60

Meiosis and Mitosis
Fertilization

The First Patterns of Differentiation 43

Anatomical Development 44
Structures and Systems in the Embryo and Fetus 44
The Embryonic Period
The Fetal Period

Preterm Births 47
Why Does Anatomical Development Progress
As It Does? 49
Diversity out of Uniformity 49
Sexual Differentiation 52
Adverse Influences on the Developing
Embryo and Fetus 53

Proliferation
Migration and Synaptogenesis
Consolidation
Myelination

Experience and Brain Development 63
Puberty and Brain Development 64

Behavioral Genetics 67
Heritability 67
Behavioral Genomics 68

Conclusions 70
Summary 72

PART II Origins

CHAPTER 3

Coming to Perceive the World 76
Vision 78
Perceiving Differences in Brightness and Acuity 79
Visual Acuity
Visual Experience and Brain Development

Color 84
Perceiving Hue and the Clustering of Hues
Categorical Perception of Color

Depth Perception 86
Cues to Depth
Which Depth Cues Predominate? Gibson’s Visual
Cliff Studies
Functional Significance of the Depth Perception System

Perceiving Patterns and Recognizing Objects 91
Pattern Perception in Other Species
Plasticity in Perceptual Development
Perceptually Grouping the World

Face Perception 95
Development of Face Perception: A Two-System Model

Facial Attractiveness

viii CONTENTS

Hearing 100
Noticing and Remembering Sounds 100
Locating Sounds 101
Perceiving Complex Sound Patterns 104

The Chemical Senses: Taste and Smell 107
Taste 107
Smell 109

Intermodal Perception 109
Conclusions 112
Summary 112

CHAPTER 4

The Emergence of Action 115
Foundations of Motor Development 116
Reflexes in Infancy 117
Theories of Motor Development 118
The Maturational Account
Dynamic Systems Theory


Perception and Action 122

CHAPTER 6

Coordination in Changing Bodies 122
Reaching 123

Connecting with the Social
World 187

Empiricist View of Eye-Limb Coordination
Constraints on Links between Eye and Limb

Navigating Space 125
Active versus Passive Visual Experience and Action
Walking and Seeing

Learning to Engage in Specific Actions 131
Early Imitation 131
The Process of Imitation
The Development of Birdsong: Variations on the
Imitation Theme

Imprinting, Action, and Critical Periods 135
Conditioning 136
Classical Conditioning
Operant Conditioning
Constraints on Learning

Conclusions 142
Summary 143

CHAPTER 5

Coming to Understand the
Physical World 145
Piaget’s Approach 146
Piaget’s Theory of Cognitive Development 147
The Sensorimotor Period in Infancy 149
Stage 1: Use of Reflexes
Stage 2: Emergence of Primary Circular Reactions
Stage 3: Appearance of Secondary Circular Reactions
Stage 4: Coordination of Secondary Circular Reactions
Stage 5: Appearance of Tertiary Circular Reactions
Stage 6: Invention of New Means through Mental
Combinations

Key Aspects of Piaget’s Theory 154
Examining the A-Not-B Error 155

Infant Knowledge and Understanding 157
Thinking about the Unseen 158
Studies of Object Permanence and Solidity
Principles That Guide How Infants Understand
Comparative Considerations

Developing Bonds between Infants and Caregivers 189
Early Perspectives on Infants’ Bonds with Others 190
Psychoanalytic Approaches to Infant-Parent Bonds 190
Learning Theory Approaches 191
Bowlby’s Ethological Approach 192

The Underpinnings of Attachment 194

Components of Attachment 194
Smiling
Clinging and Touching
Cuteness

Bases of Social Interactions 199
Contingent Responding
Social Referencing
Joint Attention and Gaze Following

Individual Differences in Attachment Style 201
Studying Attachment Styles in the Strange Situation 202
Causes of Different Attachment Styles 203
Parent Effects on Insecure Attachment
Child Effects on Insecure Attachment
Interactions of Parent Effects and Child Effects

Consequences of Different Attachment Styles 208
Correlations between Infant Attachment Styles and Children’s Social Interactions
Long-Term Links between Infant Attachment Styles and Adult Relationship
Styles

Cross-Cultural Differences in Attachment Styles 210

Effects of Early Social Deprivation 214
Social Deprivation in Humans 214
Deficits in Socially Deprived Infants
Untangling Causation

Deprivation Studies in Nonhuman Primates 218

Tactile Stimulation and Physiological Needs
Peer-Raised Infants

Critical-Period Effects? 222

Conclusions 223
Summary 224

CHAPTER 7

Understanding Causation 164
The Use of Number 166
Spatial Knowledge in Infants 169
Categorization in Infants 171

The Origins of Emotion,
Temperament, and Personality 227

Distinguishing the Physical World from
the Social World 175

Approaches to Emotional Development 229
Differentiation of Emotions in Infancy 230

Action at a Distance and Social Contingency 176
Goal and Belief Attribution 177

Conclusions 183
Summary 184

Emotional Development 228

Basic Emotions
Complex Emotions
Moral Emotions?

Perceiving and Thinking about Emotions 236
Recognizing Emotions in Others
Emotional Contagion

CONTENTS

ix


Emotional Regulation in Infancy 237

Determining Differences in Temperament 249

Situational Factors
Attentional Deployment
Response Modification

The New York Longitudinal Study
Modern Approaches to Studying Temperament
Linking Temperament to Personality Development

Evolutionary Preparedness and Emotional Development 242
Preparedness for Acquiring Certain Fears
Preparedness and the Development of Disgust

Preparedness and the Development of Other Emotions

Temperament and the Origins of Personality 247

Child–Environment Interactions and Goodness of Fit 252
Environments for “Squeaky Wheels”
Parental Influences on Temperament

Conclusions 255
Summary 256

Temperament-Based Components of Personality and Early
Development 248

PART III Developing

Competencies
CHAPTER 8

The Growth of Grammar 280

Language Development 260

Effects of Age on Language Acquisition 281

Components of Language 262
Universal Constraints on Language 263

Acquiring Language after the Critical Period 282
Acquiring American Sign Language after the

Critical Period 283
Inventing a New Language 283

Acquiring a First Language 263

The Domain Specificity of Language 284

Developmental Patterns 263

Neural Dissociations 285

The Structure and Complexity of Language 262

Prelinguistic Perception and Communication
One-Word Utterances
Multiword Utterances
Linguistic Rules

Child-Directed Speech 267

Theories of Language Acquisition 268
Behaviorist Approaches 269
Connectionist Approaches 270
Statistical Learning Approaches 270
Nativist Approaches 272

Discovering the Meanings of Words 273
Linking Words to Concepts 273
Constraints on Word Meanings 275
Perceptual Constraints

Conceptual Constraints
Pragmatic Constraints
The Nature of Constraints on Word Meanings

Developmental Changes in Word Meanings 278
Overextensions and Underextensions
Linking Features with Meanings

x CONTENTS

Aphasias
Williams Syndrome
Specific Language Impairment (SLI)

Species Specificity 288
Chimp as Child
Nonhuman Primates and Sign Language
Bonobos and Joint Attention

Language and Thought 290
Linguistic Relativity and Linguistic Determinism 290
The Sapir-Whorf Hypothesis
Color and Number
Other Influences of Language on Thought

Language as an Amplifier of Thought 292
Influences of Cognitive Development on Language 294

Language and Communication 295
Conclusions 299

Summary 300


CHAPTER 9

The Growth of Knowledge 303
Dimensions of Cognitive Development 305
Qualitative versus Quantitative Development 305
Global versus Local Patterns of Development 306
Foundational versus Emergent Constraints 306

A Closer Look at Piaget’s Theory 308
The Preoperational Period 308
The Concrete Operational Period 311
The Formal Operational Period 311
Alternative Explanations of Piaget’s Theory and Results 313
Seriation
Thinking about Classes
Conservation

Domains of Knowledge 320
Spatial Relations 321
Number 324
Biology 327
Other Domains of Thought 334
Beliefs about Physical Mechanics
Beliefs about Substance
Beliefs about Cosmology

A Developmental Disorder in Attention: ADHD 363

Biological Bases of ADHD
Misdiagnosis of ADHD

Reasoning and Thinking about Knowledge 366
Analogical Reasoning 366
Scientific Reasoning 368
Metacognition and Accessing Knowledge 370
Illusions of Knowing
Evaluating Others’ Knowledge

Three Specific Skills 372
Reading 372
Learning to Read
Teaching Reading
When Reading Is a Challenge: Dyslexia

Mathematical Reasoning 376
Growth of Mathematical Skills
Teaching Mathematics
Developing Problem-Solving Strategies

Using Symbolic Representations 378
Using Maps and Models
Children’s Drawings

Conclusions 380
Summary 381

Sociocultural Views of the Development of
Knowledge 337

CHAPTER 11

Vygotsky’s Views 337

Intelligence and Schooling 385

Conclusions 339
Summary 340

What Is Intelligence? 387

CHAPTER 10

The Growth of Cognitive Skills 343
Memory 344
Components of Memory 345
Types of Long-Term Memory 346
Explicit Memory versus Implicit Memory
Procedural Memory versus Declarative Memory
Semantic Memory versus Episodic Memory

Memory Strategies 349
Development of Metamemory 350
Memory and Expertise 352
Infantile and Early Childhood Amnesia 353
Memory Format Change Hypothesis
Neural Change Hypothesis
Cueing Hypothesis
Culture, Gender, and Early Childhood Amnesia

Emergence of Long-Term Autobiographical Memory 356

Attention 358
Attention as an Active Exploratory System 359
Three Components of Attention 359
Orienting
Alerting
Executive Functioning

The Psychometric Approach 387
Interpreting Test Scores
Correlates of Intelligence Test Scores

Psychometric Theories of Intelligence 390
Spearman’s Theory of General Intelligence
Carroll’s Three-Stratum Theory of Intelligence
Cattell’s Theory of Fluid and Crystallized Intelligence

Alternative Views of Intelligence 393
Gardner’s Theory of Multiple Intelligences
Sternberg’s Theory of Successful Intelligence

Origins of Intelligence 396
Infant Indicators of Intelligence Test Performance 396
The Heritability of Intelligence 397

Group Differences and Intelligence Tests 400
Sex Differences 400
Ethnic and “Racial” Differences 402

Explaining Group Differences 402
Are Group Differences Irrelevant?
Genetic Factors
Socioeconomic Factors
Sociocultural Stereotypes

Group Differences over Time 406

Environmental Influences on Intelligence
Test Scores 407
Enhancing Early Environmental Influences: Head Start
Programs 408
CONTENTS

xi


Implementing Cognitive Science Ideas in the
Classroom
Aptitude-Treatment Interactions

Schooling 409
Characterizing Schools 409
Two Prominent Models of Education

Creativity 417

What Schools Do 411
Schools as Socializing Agents
Schools as Cultural Institutions

Schools as Vehicles of Values

Measures of Creativity 417
The Development of Extraordinary Creativity 420

Schools and Thought 412
Cognitive Science and Teaching
Three Cognitive Science Themes for Education

Conclusions 421
Summary 422

PART IV The Self and Others

CHAPTER 12

Morality in Thought and Action 426
The Development of Moral Thought 427
Debating the Origins of Moral Thought 428
Evolutionary and Cultural Psychology and Morality 429
Characterizing the Basis of Moral Thought 430

Piaget’s Theory of Moral Development 431
Piaget’s Stages of Moral Reasoning 432
Stage 0: Premoral Development
Stage 1: The Heteronomous Stage
The Transition between Stage 1 and Stage 2
Stage 2: The Autonomous Stage

Evaluating Piaget’s Account 434

Distinguishing Morality from Conventions
Accounting for Intentions
Immanent Justice across Cultures

The Development of Moral Behavior 444
Consistency of Moral Behavior 444
Antisocial and Prosocial Behavior 448
Antisocial Behavior
Prosocial Behavior

Temperament, Personality, and Moral
Behavior 452
Self-Regulation
Arousal Level and Positive Emotionality
Empathy

Social Influences on Moral Behavior 456
Punishment and Learning Theories
Modeling Theory and Moral Behaviors
Parent-Child Interactions and the Development of
Conscience

Conclusions 463
Summary 464

Kohlberg’s Theory of Moral Reasoning 437
Kohlberg’s Stages of Moral Reasoning 437
Evaluating Kohlberg’s Theory 438
Unclear Stages
Cross-Cultural Variations

Possible Gender Biases

CHAPTER 13

Knowing Ourselves,
Knowing Others 467

Alternative Theories of Moral Development 440

Self-Concepts and Self-Representations 468

Gilligan’s Theory of Moral Development 440
A Pluralistic Approach to the Development of Moral Thought 441

Senses of Self 468

Contributions from Personality Psychology
Contributions from Cultural Psychology
Domain-Specific Moral Reasoning

xii CONTENTS

Neisser’s Five Senses of Self

The Mirror Test and Self-Concept 471
Variations on the Mirror Test

Gender Identity 472

Developing a Sense of Self-Worth 474
Self-Esteem 474
Self-Efficacy 476

Self-Regulation 477
Brain Maturation and the Development of Self-Regulation 480
Contextual Influences on Self-Regulation 481

Developing a Theory of Mind 482
Early Aspects of Theory of Mind 483
Comparative Perspectives on Theory of Mind 484
Understanding False Beliefs 487
Evaluating the False-Belief Task

A Theory of Mind Module? 490
Beyond False Beliefs 492

Working Parents and Child Care 529
Changes in Family Structures 530
Single-Parent Families
Same-Sex Parents
Divorce
Blended Families

Child Abuse 536
Effects of Abuse 537
Explaining the Cycle of Abuse 537
Foster Care 538

Conclusions 539

Summary 540

Making Attributions about Ourselves and Others 493

CHAPTER 15

Emerging Explanations of Behavior 493
Traits and Optimism 496
Attribution, Motivation, and Creativity 497

Becoming Part of the
Community 543

Conclusions 499
Summary 501

Levels of Affiliation 544

CHAPTER 14

Becoming Part of the Family 503
Parenting 505
Parenting Styles 506
Parenting Contexts 508
Parenting across Cultures
Parenting across Socioeconomic Groups
The Ecological Systems Approach

Interventions to Improve Parenting 510
Parent Effects in Relation to Other Influences 511

Child Effects
Genetic Effects

The Interactionist Approach to Family Dynamics 514
Gender Socialization in the Family: A Web of Interacting
Influences 515

Siblings and Family Dynamics 518
Birth Order Effects 518
An Interactionist Approach to Birth Order Effects

Sibling Relationships and Socialization 520
Jealousy and Conflict between Siblings
Siblings and Social Understanding
Sibling Relationships within the Family

Changes in the Family 525
Changes in Parents’ Age 525
Changes in Family Size 527

The Changing Nature of Social Interactions 545
Developing Relationships 546
Friends
Imaginary Companions
Bully-Victim Relationships
Enemies
Dating and Romantic Relationships

Social Groups 553
Cliques and Crowds

Sociometric Status and Social Interaction

Developmental Patterns in Levels of Affiliation 558
Social Network Effects 558

Media Influences on Development 559
Television 560
The Pervasiveness of Television Watching
Changes in Television Watching with Age
Positive Effects of Television
Negative Cognitive Effects of Television
Negative Social Effects of Television
Responding to the Influences of Television Violence
Stereotyping in the Media

Video Games, Computers, and the Internet 569
Video Games
Internet Communities

Roles in the Larger Culture 574
Distinctive Cultural and Subcultural Roles 574
Gender Roles and Stereotyping 576

Conclusions 581
Summary 582

CONTENTS

xiii

PART V Broader Developmental

Context
CHAPTER 16

Psychopathology in Childhood 586
Autism 588
Features of Autism 588
Diagnosis of Autism 589
Incidence of Autism 589
Causal Factors 590

Anxiety Disorders 592
Incidence of Anxiety Disorders 592
Causal Factors 593
Cognitive Factors
Biological Factors

Schizophrenia 614
Features of Schizophrenia 614
Causal Factors 616
Early-Onset Schizophrenia 619

Treatment of Childhood Psychopathologies 619
Behavioral Therapies 619
Cognitive-Behavioral Therapy 620
Psychoanalytic Therapies 621
Family Therapies 622
Pharmacological Treatments 622

Evaluating Therapies 624

Conclusions 625
Summary 625

Obsessive-Compulsive Disorder 595
Types of Obsessive-Compulsive Disorder
Incidence of Obsessive-Compulsive Disorder
Diagnosis of Obsessive-Compulsive Disorder
Causal Factors

Eating Disorders 598
Anorexia Nervosa 598
Incidence of Anorexia
Cognitive Distortions in Anorexia
Genetic and Environmental Causal Factors

Bulimia Nervosa 602
Incidence of Bulimia
Causal Factors

Depression 603
Unipolar Depression 604
Biological Causes
Social Causes
Cognitive Causes

Bipolar Disorder 607
Causal Factors
Diagnosis of Bipolar Disorder

Conduct Disorder: The Case of Psychopathy 609
Features of Psychopathy 610
Diagnosis of Psychopathy 611
Causal Factors 612

xiv CONTENTS

CHAPTER 17

Development after Childhood
and Adolescence 629
Physical and Physiological Changes in Adulthood 630
Cognitive Changes in Adulthood 635
Reaction Time and Speed of Processing 635
Memory, Higher Cognitive Functions, and Reasoning 635
Daily Activities and Cognitive Aging 639
Circadian Rhythms, Cognition, and the Lifespan 641

Changes in Personality in the Lifespan: Individual and
Group Changes 643
Changes in Individuals 643
Stressful Life Events 644
Group Changes 645

Stages of Life? 648
Erik Erikson’s Approach 648
Stage 1: Trust versus Mistrust
Stage 2: Autonomy versus Shame/Doubt
Stage 3: Initiative versus Guilt

Stage 4: Industry versus Inferiority


Stage 5: Identity versus Role Confusion
Stage 6: Intimacy versus Isolation
Stage 7: Generativity versus Stagnation
Stage 8: Integrity versus Despair

Understanding Stages of Adult Development 652

What Does It Mean to Be Old? 652
Stereotypes and Ageism 654
Cultural Variation in Stereotypes and Ageism? 655

EPILOGUE 659
GLOSSARY G-1
REFERENCES R-1
CREDITS AND ACKNOWLEDGMENTS C-1
NAME INDEX N-1
SUBJECT INDEX S-1

Conclusions 656
Summary 657

CONTENTS

xv


Boxed Features

Development and Social Policy
What Kinds of Experimental Research Are Justified? 25
Visiting Nurses, Prenatal Care, and Child Development 51
Legislating Early Stimulation 106
Can a Toddler’s Motor Development Be Accelerated? 137
The Myth of the First 3 Years 181
Day Care and Attachment 212
The Causes and Consequences of Problems in Emotional
Regulation 244
The Cognitive Effects of Bilingualism 296
Sputnik and Intuitive Science 328

A Language Gene? 287
Biological Knowledge and Exposure to Nature 333
The Genetics of Dyslexia 375
A g for Emotional Intelligence? 395
Moral Dumbfounding: Judgment or Intuition? 446
Theory of Mind in Dogs? 486
Epigenetics and Families 512
The Development of Racial and Ethnic Occupational
Stereotypes 578
Co-rumination, Gender, and Depression 608
Why Do We Age and Why Do We Live as Long as We
Do? 632

Children as Witnesses 360
Computers and e-Learning in the Schools 418
At What Age Should an Offender Be Treated as an
Adult? 457

Scientific Method Boxes
Diet and Methylation 40

Potential Drawbacks of Self-Esteem 478

Intersensory Perception at Birth 111

China’s One-Child Policy 522

The Genetics of Early Handedness 124

Free Speech and Children’s Rights 570

Agents and Order 182

Prescribing Psychoactive Medications to Young
Children 623

Internal Working Models and Attachment Styles 209

When Is It Acceptable to Deprive the Elderly of Some
Rights? 650

Early Use of Syntax to Guide Learning New Words 276

New Directions in Developmental Research

Maternal Reminiscing and Children’s Autobiographical
Memories 357

Measuring Infants’ Brain Function: Near-Infrared
Spectroscopy (NIRS) 21

Direct versus Inquiry-Based Methods of Instruction 414

Repairing Brain Damage Later in Life? 66
Cochlear Implants and the Question of Critical Periods for
Auditory Processing 102

Inferring Actions from Emotions 238
Early Motivation to Learn about Kinds over Individuals 318

Instrumental Helping in Toddlers 450
Gaze Following in Human Infants and Great Apes 485
Training Parents to Moderate Sibling Conflicts 524

Mirror Neurons and Early Imitation 134

Effects of “Minimal” Group Affiliations 580

Advances in Infant Eye-Tracking Methods 172

Psychopathy and Fear Processing 613

New Insights into the Role of the Father 204

The Positivity Bias in Older Adults 647

The Effect of Parenting on Emotion Processing in
Children 240

xvi


Preface
have been deeply involved in teaching introductory
courses in developmental psychology since my first year
as a teaching assistant at Stanford University in 1973. And
I have taught my own lecture course since joining the faculty
of Cornell University in 1977. While there have always
been a range of available textbooks for this course, I have
always felt the need for a book that comes closer to my own
vision of how developmental psychology should be taught.
I thought that there should be a book celebrating the beauty
and incredible complexity of psychological development
while also offering clear and compelling accounts of why
development occurs as it does. Equally important, I wanted
a book that showed how an understanding of development is
essential to understanding psychological processes in adults
and how a developmental perspective offers unique insights
into mature psychological functioning. I believed a textbook
on developmental psychology should illustrate common
developmental themes across all areas of psychology while
also explaining how trajectories within broad domains can
each take on their own special characteristics. And I thought
that a textbook should discuss commonalities and contrasts
across cultures and even across species, as well as considering
how psychological development fits into a broader context
of biological and neurobiological development. Moreover,
I believed that to fully illuminate the study of development,
a textbook should situate psychology within a larger set of

disciplines—including anthropology, computer science,
linguistics, neuroscience, philosophy, and sociology—that
intersected with psychology. Different texts touched on some
of these ideas, but none covered all of them, and many did
not seem to have a single voice that wove topics and themes
into an integrated whole.
Finally, and perhaps most immediately compelling,
the birth of our first son in 1981 made me want to dive
much more deeply into the broad literature on all aspects
of psychological development. But this also created an
unanticipated challenge. As any parent knows, a newborn
child is an instant lesson into just how much we don’t know
about development, a lesson that keeps expanding in scope
as that child grows up. Moreover, as soon as I thought I was

I

making some progress in linking scholarly work to my own
personal experiences, our second son was born, and then
our third son. And each child offered dramatic new insights
and perspectives into development. Many years later, after
our youngest son finished college and was out in the world,
it was finally time to finish writing this textbook.
I have worked on various drafts of this book for over
30 years, writing and rewriting as my insights changed and
the field of developmental psychology itself has undergone
dramatic changes. I have also used drafts of the text in my
courses at Yale for over a decade, constantly refining it in
response to feedback from my ever gracious and helpful
students. Throughout this entire process, which has

continued throughout most of my academic career, I have
written and rewritten three or four drafts of the entire
book, finally winnowing down the material into the book
that you have before you. In the course of writing the
book, I have gained an immense appreciation for all of my
colleagues in the field who have contributed so spectacularly
to the flowering of the discipline over the past few decades.
Developmental psychology today is an incredibly vibrant and
exciting field that is far more closely connected to the rest of
the psychology and other disciplines than ever before, and
my excitement and pleasure in writing about it has increased
every year. I hope that some of that excitement and pleasure
is contagious to readers of this text. I deeply appreciate how
this first edition is only the beginning of an evolutionary
process that will continue in future editions, but after three
decades of immersion in this project, it finally seemed time
to take it out of my classroom and share it more widely.

Overarching Themes
and Principles
There are fascinating themes and principles that keep
recurring throughout developmental psychology and that
help to show how different threads of research mutually
xvii


reinforce each other. These themes and principles serve
as constant touchstones for organizing the material in the
book. Seven themes stand out as recurring most frequently.
One key theme is the centrality of feedback loops, both

positive and negative. Development is rarely, if ever, a oneway process in which one factor causes another to happen
without some kind of feedback. Parents influence their
children, who in turn influence their parents, in cycles
of interaction that can reinforce desirable outcomes or
aggravate undesirable ones. The simple acts of learning
to walk and successfully reaching toward objects involve
constant feedback loops between what a child sees and
how she acts. Even at the neural level, the growth of neural
circuits can depend on feedback from experience, which in
turn can change how future events are experienced. In all
areas of development, we will see the central importance of
feedback loops.
A second major theme is that development is a dynamic
exploratory process in which the child is more than a passive
recipient of experiences and information. When children are
viewed as actively engaging with the world, it is much easier
to understand development, whether it is development of
perception, cognition, motivation, or morality.
A third theme is to see that development is constrained
by factors that arise both internally from within the child and
externally from the environment. While constraints may
seem to somehow hinder development they may actually
foster development by acting as scaffolds and guiding
frameworks that make otherwise overwhelming problems of
learning and skill development manageable. We will see the
value of constraints and how they can guide development
in many areas, while still allowing for enormous diversity
of outcomes. Discussions of constraints also allow for a
balanced treatment of the tradeoffs between nativist and
empiricist views of development and the related, often

needlessly contentious, nature/nurture debate.
A fourth theme is to focus on what children can do and
how their basic capacities emerge and serve as foundations for
later development, as opposed to focusing on what children
cannot do compared with older children and adults. While
younger children and infants certainly have limitations that
are not found in later years, it is almost always more fruitful
to avoid “deficit models” of development and instead ask
how children progress as they grow.
A related fifth theme that occurs in all areas of development
is that infants and children usually have some viable version of
a skill throughout development; they rarely go “offline” as they
retool or improve on a system. Just as the human heart must
beat continuously as it goes through remarkable anatomical
and physiological changes from its early embryonic stages
to birth and beyond, most perceptual, cognitive, emotional,
and social systems must have some working functional
capacity throughout development. For example, infants’
xviii PREFACE

emotional states have functional values both for themselves
and for their interactions with others, and while their
emotions change considerably in the first year of life,
infants cannot simply shut down their emotional systems
when transitioning to new kinds of emotions or emotional
interaction patterns. The same is true for everything from
language to friendship and is closely related to the idea that
the most functionally vital aspects of systems often appear
earliest in both development and in the evolutionary history
of organisms.

A sixth theme is the ever-present links and interdependencies
between different areas of development. It simply isn’t possible
to consider cognitive development without also considering
social and emotional development, just as understanding
social development depends on related changes in cognitive
development, and a full account of emotional development
depends on understanding both social and cognitive
development. We will often focus primarily on one area at a
time, but we will always take into account how the different
areas of development also interact and must be understood
in their entirety to obtain a full picture of what develops.
A final theme is that developmental psychology is not
just a human-based process. All organisms with significant
behavioral components grow from immature states to
mature states and show fascinating patterns of change
and constancy. Comparisons across these organisms and
especially with humans are not just interesting in their own
right, they can also greatly help us to understand what is
unique about human psychological development, as well as
telling us about what kinds of developmental problems tend
to converge on one common class of solutions and what
kinds of problems embrace an enormous diversity of possible
solutions. This comparative perspective also highlights the
ways in which evolutionary considerations can inform
thinking about development. These seven themes and
principles recur throughout this book and provide a way
of weaving together all of the book’s content to create an
integrated and more memorable whole that reveals larger
developmental patterns.

Linking Theory and Evidence
Developmental psychology has emerged robustly in the
past few decades as a full-fledged science in which scholars
propose theories and models and then test them rigorously.
This book celebrates the ways in which ideas, many of
which have been with us for centuries, are now being tested
in carefully designed experiments or through powerful new
statistical analyses of large data sets. It is fascinating to see
how classic issues are now coming into much clearer focus
as a result of clever new studies. Throughout this text, we


will encounter theories, sometimes conflicting theories, and
ask how they can be tested and what the current evidence
tells us. In many cases, the debate continues with more than
one view remaining viable, but also with a much better
understanding of the research path forward.
I am convinced that even the most complex and intricate
theories of development, ranging from neural growth
patterns to changing social network analyses, can be
explained in such a way that any introductory student can
appreciate their key dimensions and how to evaluate them
in light of the right kinds of studies and evidence emerging
from those studies. All the theories and studies in this text
have been written up, reviewed, and rewritten several times
to ensure that they are clear and accessible and that the
links to empirical research are compelling. I want all the
readers of this text to be able to step into the shoes of leading
investigators in developmental psychology so that they can
understand what drove the researchers both in terms of

theory and their passion to design and execute studies to
answer developmental questions.

Integrated Treatment
As already is clear from the way our themes and principles
cut across diverse areas, a hallmark of this text is the way
it integrates material across all the chapters and keeps
illustrating how certain patterns and ideas keep recurring.
There are several forms of such integration throughout
the book. Some themes recur across all the different times
of development, from the prenatal period to the period
of old age. Some themes recur across domains, ranging
from perceptual to cognitive to social to moral domains.
Some themes recur across cultures and even across species.
The child develops as a whole person in which many
different psychological systems are linked together and
depend on each other and which have strong continuities
with earlier and later periods of development. This book
reflects that integration both in terms of how it has been
organized and written and in terms of my own perspective.
The book is topically organized within a chronological
framework, which serves to provide maximum integrations
in distinctive developmental periods, as well as providing
more coherent treatments of each area of development. As a
single author of this book, an increasingly vanishing breed
of introductory text authors, I have been able to develop
a voice and lines of thought that are woven throughout
every chapter and that mutually reinforce each other. After
reading a chapter or two, students should have a constantly
building feeling of familiarity with ideas and approaches

that helps make everything hang together. Near the end of
the book, I offer a different kind of integration through a

discussion of psychopathology in development. More than
just a review of the psychopathology literature, Chapter 16
shows how aspects of development that are covered in earlier
chapters, ranging from brain development to cognitive
executive functioning to socialization, come together in
an interwoven manner to contribute to the emergence of
various forms of psychopathology. Students will see how all
that they have learned bears on powerful and compelling
problems. They will then experience a different form of
integration of the same range of topics in the final chapter,
which considers development after childhood and in which
there is a fascinating set of questions that can have some
striking resonances to earlier developmental questions and
themes. I have taken great pains to present the full spectrum
of theories and approaches but always with an eye toward
how they relate to each other and to larger developmental
issues that transcend any one school of thought. In doing
so, I have immersed myself in reading the literature on
different aspects of development, as well as engaging in
many conversations and corresponding with experts across
many disciplines, far more deeply than I ever could have
imagined I would do when I first started on this project.
The entire process has fed back into this book, and it has
been great fun as well!

Distinctive Pedagogical
Features

To best convey the themes and principles, to set forth the
relations between theory and evidence, and to provide the
most integrated treatment possible, this book has several
distinctive pedagogical features. Throughout every chapter,
there are comprehension checkup questions, a pedagogical
tool that enables readers to immediately know if they
have mastered the key issues they have just encountered.
In each chapter, there are also highlighted key terms that
are defined in the Glossary of the book. Each chapter ends
with a conclusion that brings together the key ideas and
often offers a novel integrative insight. The summaries
that follow the conclusions are comprehensive digests of
the entire chapter in a bulleted format. Any students who
can clearly recognize and elaborate on each bulleted point
will have a good sense of how well they have mastered
the chapter. Finally, at the end of each chapter, for more
in-depth consideration of the material, there are sets of
extended thought questions that challenge students to
consider a problem more thoroughly.
Every chapter has a box that is concerned with a social
policy issue connected to material in the chapter so that
students can see how basic research can be linked to
PREFACE

xix


important and socially relevant real-world issues. A second
box in each chapter is concerned with an example of an
exciting new direction of developmental research so students

can see how the field continues to evolve through innovative
research initiatives. It is an important way of illustrating
how developmental psychology is a dynamic, active field.
A third box in each chapter illustrates in more detail the
methodology of scientific research relevant to the topics
of that chapter. The purpose here is to show in a manner
closely analogous to posters at scientific conferences how
an experiment is organized in terms of hypothesis, method,
results, and conclusion, and to include illustrations of the
experimental setup and results. These boxes are somewhat
simpler than most posters at meetings, but they very much
capture their spirit.
Throughout the book, there are brief historical discussions
of research topics that make clear how current ideas and
research emerged from older traditions. There is also careful
documentation of cutting-edge research that serves not only
to ground the research in particular studies but also serves
as a rich source of references for further explorations by
students, references that are also available on the instructor
Web site and in prepared LMS materials available free of
charge to every instructor using the book.
In the end, these pedagogical devices all serve the
overarching goal of this book, which is to get to the heart
of developmental psychology. My aim is to expose readers
to developmental psychology’s big questions in an engaging
and compelling way that invites students to join researchers
in one of the most lively and fascinating areas of intellectual
inquiry that also has immense personal relevance and social
importance.

Supplementary Materials
Our supplements package was developed based on data from
a survey of 60 instructors currently teaching developmental
psychology at a wide variety of schools. Our book-specific
resources are easy to access in one place through wwnorton
.com/instructors. They are also searchable on the Interactive
Instructor’s Guide, making lecture planning easy.

Presentation Tools
• Lecture PowerPoints offer images and instructor-only
lecture notes that include additional examples and
teaching suggestions, which will help ease the transition
to using a new textbook. Each chapter also includes an
optional set of slides that cover the research behind a
concept covered in the chapter to illustrate how the science
xx PREFACE

of developmental psychology leads to the theories students
are learning about in class.
The Developmental Psychology Lecture PowerPoints were
written by David Barner and Jessica Sullivan, both of
whom are at University of California, San Diego.
• All of the art in the book is available as PowerPoints and
JPEGs to make creating custom presentation materials
easy.
• Presentation tools are downloadable at wwnorton.com/
instructors.

Videos
• Chapter Opening Videos from Frank Keil himself serve as

an introduction to the chapter topics and help convey his
enthusiasm and voice to the reader.
• Classroom Videos with discussion questions feature
enactments of classic experiments and demonstrate a
variety of characteristics from varying developmental
periods, showing developmental psychology as a science in
action. The Developmental Psychology videos were curated
by Tasha Howe of Humboldt State University.
• Videos are available at wwnorton.com/instructors as part
of the Interactive Instructor’s Guide and as part of our
LMS-ready materials.

Interactive Instructor’s Guide
• The searchable Interactive Instructor’s Guide offers classroom activity suggestions with print-ready handouts, chapter
opening videos, and classroom videos with discussion
questions. The Developmental Psychology videos were curated
by Tasha Howe of Humboldt State University, and the
activities were written by Melissa Barnett at the University
of Arizona.
• The Interactive Instructor’s Guide is downloadable from
wwnorton.com/instructors.

Test Bank
• The Test Bank for Developmental Psychology is designed to
help instructors prepare their exams. The Test Bank has
been developed using the Norton Assessment Guidelines,
and each chapter of the Test Bank consists of five
question types classified according to the first five levels
of Bloom’s taxonomy of knowledge types: remembering,
understanding, applying, analyzing, and evaluating.

Questions are further classified by section and difficulty,
making it easy to construct tests and quizzes that are
meaningful and diagnostic.


• The Test Bank questions were written by Thompson Davis
of Louisiana State University and Lisa Rosen of Texas
Woman’s University, with Tasha Howe of Humboldt State
University.
• The Test Bank is available in paperback and on disk; it is
also downloadable in PDF, RTF, or ExamView formats
from wwnorton.com/instructors.

of the print book and allow students to highlight and take
notes with ease, print chapters as needed, and search the text.
Norton eBooks are available online and as downloadable
PDFs. They can be purchased directly from our Web site, or
with a registration folder that can be sold in the bookstore.

Acknowledgments
Norton Coursepacks: Our Content,
Your Course
• Easily add high-quality Norton digital media to your
online, hybrid, or lecture course—all at no cost. Norton
Coursepacks work with and leverage your existing Learning
Management System, so there’s no new system to learn, and
access is free and easy. Comprehensive coursepacks are ready
to use, right from the start, but they are easy to customize,
using the system you already know and understand. The
Developmental Psychology Coursepack includes classroom

videos with discussion questions, Quiz+ review questions,
and flashcards available for the students (or assignable as
instructors see fit), as well as the Test Bank.
• Quiz questions were written by Thompson Davis of
Louisiana State University and Lisa Rosen of Texas
Woman’s University, with Tasha Howe of Humboldt State
University.
• All of these materials are downloadable in Blackboard,
Moodle, D2L, Angel, and Canvas formats.

eBook
• Same great book, a fraction of the price.
• An affordable and convenient alternative to the printed
textbook, Norton eBooks retain the content and design

My deepest debt goes to my wife Kristi Lockhart, who was
assigned to the same office as me on our first day of graduate
school and who has been my one true love and colleague ever
since. Kristi has made major career sacrifices for the sake of
our family and my career and has always done so with great
generosity and good humor, spreading that spirit of generosity
and good humor to our children as well. As a parent and partner
she has been loving, supportive, and playful in ways that have
sustained and inspired all of us. I am infinitely fortunate that
she is the love of my life and marvel every day that she was
willing to spend her life with me. She has taught me more
about children, parenting, and family dynamics than all other
sources combined and has been the best parent ever. Through
countless discussions with her about almost all the topics in
this book and through listening to her many observations

about children, I have been a most grateful recipient of her
wisdom. I owe her everything. I have also shared with Kristi in
the delight of watching our three sons grow, each in their own
ways, into remarkable young men. From their first moments
as newborns to their lives as young adults, Derek, Dylan, and
Martin have taught us both many volumes about development
and continue to do so, as well as providing us with the most
rewarding and meaningful experiences of our lives. Kristi,
Derek, Dylan, and Martin have also been incredibly patient
and tolerant of my obsession with this book and the ways it
has hovered over all of us for decades. These two photos of our

PREFACE

xxi


family cover only part of the entire period of writing this book,
but they show the passage of time during which I was writing
it. The many hours I have spent working on this book have
been all too evident to every member of my family, and they
all have been tremendously gracious about its intrusions into
their lives. I thank all of them from the bottom of my heart
for their support, their inspiration, and their forbearance and
I thank the heavens that I was lucky enough to be part of this
family.
Certain people at W. W. Norton also deserve extraordinary
thanks, starting with Don Lamm and Don Fusting,
who originally signed me up to write the book years ago.
I appreciate the support I have received from the Acquisitions

Editors Sheri Shavely, Roby Harrington, Jon Durbin, Cathy
Wick, and, especially recently, Aaron Javsicas, who made
sure the whole project met critical deadlines and who has
been very helpful in selecting art. I have also been blessed
with brilliant copy editing by Janet Greenblatt and project
editing by Rachel Mayer. I thank Vanessa Drake-Johnson,
who served as an early Developmental Editor of the book,
and Photo Editor Mike Fodera, Photo Researchers Donna
Ranieri and Julie Tesser, Media Editor Callinda Taylor,
Editorial Assistant Shira Averbuch, Production Manager
Eric Pier-Hocking, and Marketing Manager Lauren
Winkler. I also would like to thank Jonathan Kominsky
who worked on the art manuscript in New Haven.
But I must especially acknowledge the massive contributions made by two Developmental Editors, Sarah Mann and
Sandy Lifland. Sarah became involved in the project in 2007
and went through the entire text and asked me probing questions about what I really wanted to say and if I was saying it
in the best and briefest ways possible. She helped enormously
to shape what had become a far too long body of text into
something much more workable. Even more critically, Sandy
Lifland has had a profound influence. She is a legendary editor who early on gave me challenging feedback on the crude
first drafts of this book and made me realize just how much
more I had to do if I wanted to write the book I really envisioned. She then rejoined the project in 2011 and worked
full time on the book until its publication. We studied, considered, and often extensively discussed every word of text,
every line in every figure and graph for ways that they could
be clearer, better connected to the big ideas of the book and
to the basic scientific literature. Sandy herself read hundreds
of original articles to understand more deeply what I had in
mind and to ensure that I was getting across to the reader
exactly what I really intended. She also kindly pointed out
to me several cases where I still wasn’t clear in my own head

about what I actually wanted to say. I honestly cannot imagine a better editor who cared more about creating a product
of real intellectual and aesthetic value.
This book has been reviewed through the years by
many scholars who have been involved in all stages of its
xxii PREFACE

evolution, sometimes sending me extensive comments on
earlier drafts, other times providing confirmatory reviews to
Norton editors about the near final drafts. I have included
the affiliations of the reviewers at the time that they wrote
their reviews, and some may since have moved on to other
colleges and universities. I deeply appreciate all the work
that the reviewers have done and thank the following:
Joseph Allen, University of Virginia
Richard Aslin, University of Rochester
Terry Au, University of Hong Kong
Melissa Barnett, University of Arizona
Kymberley Bennett, Indiana State University
Paul Bloom, Yale University
Amanda Brandone, Lehigh University
Sara Broaders, Northwestern University
Gwen Broude, Vassar College
Jean Burr, Hamilton College
Joseph Campos, University of California, Berkeley
Carol Cheatham, University of North Carolina
Judith Danovitch, Michigan State University
Daniel Dickman, Ivy Tech Community College of Indiana
Ann Edworthy, Swansea Metropolitan University
Leanne Franklin, Cardiff Metropolitan University
Janet Frick, University of Georgia

Jeffrey Gagne, University of Texas at Arlington
Susan Gelman, University of Michigan
Gilbert Gottlieb, University of North Carolina, Chapel Hill
Joan Grusec, University of Toronto
Amy Halberstadt, North Carolina State University
Jacqui Harrison, University of Bolton
Brett Hayes, University of New South Wales
Fay Julal, Southampton Solent University
Robert Kavanaugh, Williams College
Rachel Keen, University of Massachusetts, Amherst
Debby Kemler Nelson, Swarthmore College
Susan Kemper, University of Kansas
Katherine Kinzler, University of Chicago
Kristin Lagattuta, University of California, Davis
Alan Leslie, Rutgers University
Robert Lickliter, Virginia Tech
Gary Marcus, New York University
Ellen Markman, Stanford University
Lori Markson, University of California, Berkeley
Carol Murphy, National University of Ireland, Maynooth
Simone Nguyen, University of North Carolina, Wilmington
Bjorn Nilsson, Skovde University College
Samuel Putnam, University of Oregon
Philippe Rochat, Emory University
Lisa Rosen, Texas Women’s University
Karl Rosengren, Northwestern University
Paul Rozin, University of Pennsylvania
Jenny Saffran, University of Wisconsin, Madison

Rose Scott, University of California, Merced
Meghan Sinton, College of William and Mary
Susan Sonnenschein, University of Maryland, Baltimore
County
Hiroko Sotozaki, Western Illinois University
Caroline Stanley, Wilmington College of Ohio
Michael Steele, University of Utah
Catherine Tamis-LaMonda, New York University
Ross Thompson, University of Nebraska
Elliot Turiel, University of California, Berkeley
Eva Twetman, Halmstad University College
Mike vanDuuren, University of Winchester
Kristy vanMarle, University of Missouri
Peter Vishton, William & Mary College
Maria Wong, Idaho State University
Fei Xu, University of California, Berkeley

I am also grateful to those scholars who have written the
ancillaries: Tasha Howe, Humboldt State University, who
worked on the Test Bank, Student Study Quizzes, and Video
Curation; Thompson Davis III, Louisiana State University,
and Lisa Rosen, Texas Woman’s University, both of whom
worked on the Test Bank and Student Study Quizzes; Melissa
Barnett, University of Arizona, who worked on the Classroom
Activities; and David Barner, University of California, San
Diego, who with the help of Jessica Sullivan, worked on the
Lecture PowerPoints.
Finally, I thank those many colleagues at Cornell and
Yale who have inspired and educated me on a daily basis.
Frank Keil

August 2013

PREFACE

xxiii