Developmental Psychology Research Paper

We can give only the broadest outline of the history of the field of developmental psychology. There are many complexities that we have had to ignore. We hope that this overview will whet the reader’s appetite for further exploration. Fuller reviews of our historical roots are available in Parke, Ornstein, Rieser, and Zahn-Waxler (1994) and Cairns (1998), and a reprint series of original articles and volumes by earlier theorists is available in Wozniak (1993a, 1993b, 1994, 1995).

We have divided the history of developmental psychology into five time periods—the beginning years of developmental psychology (1880–1914), the period of institutionalization and fragmentation (1915–1940), the era of expansion (1940–1960), the rise of contemporary themes (1960–1985), and the current period (1985 to present). Across these periods, we discuss recurring issues of theory and method to illustrate the ways in which there has been both constancy and change in developmental psychologists’ views of the central issues of the field. We argue that, in many regards, there have been major strides in the subtlety of the distinctions and the sophistication of the measurements and designs brought to bear on developmental questions. At the same time, there is much consistency between the perspectives of our ancestors of a century ago and the views of contemporary developmental theorists.

Another thesis is that the agenda of contemporary developmental psychology has more in common with the field’s agenda from the turn of the century than with the agenda of the middle era (1920–1960). This middle period, with its emphasis on behaviorist and normative development, its focus on experimental child psychology and social learning theory, was a sharp departure from the origins of the field. What Cairns noted two decades ago is still true today: “An overview of the past suggests that today’s investigators are as much determined by history as they are makers of it. The major issues of the present appear to be, in a large measure, the same ones that thoughtful contributors to the science have addressed in the past” (Cairns, 1983, p. 90).

Why are we returning to the concerns of our distant past? One reason is that our forebears were wise in their choice of questions and raised enduring issues. Another reason is that, in the middle period, developmentalists took some detours away from the original goals of the field in their enthusiasm for establishing a separate science on the basis of positivistic principles. The field’s behavioristic focus promoted a proliferation of excellent methods and technological advances but ignored basic questions of biology, consciousness, and cognition. Today, as the beneficiaries of both the early and the middle eras, we are in a position to ask again the old questions and address them in more methodologically sophisticated ways.

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DEVELOPMENTAL PSYCHOLOGY IN THE THE BEGINNING YEARS (1880–1914)

The beginning years of the field of development can be characterized in two ways. One way is to describe the figures who first forged the field; the other way is to describe their positions in terms of modern theoretical distinctions.

THE FOUNDERS OF DEVELOPMENTAL PSYCHOLOGY

When the field of child psychology was established as a separate and distinctive field, two sets of influential individuals were involved. One group provided the institutional and organizational support for the new discipline of psychology; the second group provided ideas and methods for the new science of developmental psychology. G. Stanley Hall led the first group; James Mark Baldwin, Sigmund Freud, and Albert Binet formed the second.

The intellectual figure who anticipated the emergence of the distinctive field of developmental psychology and who influenced the thinking of all these early figures was not a psychologist, however, but the biologist, naturalist, and architect of evolutionary theory, Charles Darwin (1809–1882). Darwin provided the intellectual foundation for a science of development by arguing that human development was governed by a set of discoverable natural laws. This central thesis, in combination with Darwin’s own early experimental studies of infants’ emotional and perceptual abilities, paved the way for later scientific analysis of children’s development.

G. Stanley Hall (1844–1924) was a cofounder and first president of the American Psychological Association and the founder of the first professional journal on development, Pedagogical Seminary. In 1909, Hall, as president of Clark University, invited Sigmund Freud to an international conference involving American and European psychologists and psychoanalysts. This was a landmark meeting; it introduced Freud and his psychoanalytic ideas to an American audience, and those ideas shaped the thinking of developmental scholars in the United States for the next half century. As a theorist and methodologist, Hall made more limited contributions (see Ross, 1972; White, 1992). He did introduce the questionnaire as a way to explore the contents of children’s minds—in fact, between 1894 and 1914 he published 194 questionnaires (White, 1992)—but his nonrandom sampling strategies, his imprecise wording of questions, and his nonstandardized mode of administering the questionnaires made the work more suggestive than definitive. Hall and his contemporaries at the turn of the century had limited knowledge of sampling techniques and issues of generalizability, and they chose samples of convenience; unfortunately, these highly selected samples were of unknown representativeness. Hall is perhaps best known for his recognition that adolescence is a unique period of development with a variety of concomitant shifts in biology, cognition, and social relationships (Hall, 1904).

Hall’s contemporary, James Mark Baldwin (1860–1934), was less of a facilitator but more of a theorist. He held positions at the University of Toronto, where he established the first experimental psychology laboratory in North America, and later at Princeton University and Johns Hopkins University. Although he was a talented experimentalist, it was his theoretical work that secured his position in the history of developmental psychology. In his extensive theoretical writings, he articulated a variety of themes, which in retrospect appear surprisingly contemporary (Baldwin, 1894, 1895, 1897). First, he developed a stage theory of development, which was remarkably similar to Piaget’s. As Piaget would later do, Baldwin set out a series of stages of development for mental processes, which were to a substantial extent based on observations of his own children. Even more than Piaget, he recognized the interplay between social and cognitive development and championed the study of the self and the need to examine different units of analysis (individual, dyad, and group). Unfortunately, Baldwin’s contribution was limited because of the short duration of his career, which ended abruptly as the result of a personal scandal. In 1908, he was forced to resign from Johns Hopkins after being caught in a raid on a house of prostitution. He spent the rest of his career in Mexico and Europe, where he continued to write about development as well as world peace. A second reason for his limited influence was his failure to develop empirical paradigms to test his ideas. As is always the case in science, theory without a clear way of evaluating the underlying notion is of limited value to the field. In spite of his lack of data, his ideas are remarkably modern. It is now recognized that “Baldwin stands alongside William James as one of the primary intellectual forces involved in the founding of American psychology as a science” (Cairns, 1994, p. 129).

At the time, however, it was Sigmund Freud (1856–1939) who influenced American developmental psychology. Freud offered both a theory of development based on psychosexual stages and a method of study, psychoanalysis (Freud, 1900, 1905, 1910). Freud taught at the University of Vienna but devoted himself largely to clinical work with neurotic patients and to a prolific writing career. In spite of the fact that he did not treat children, he developed a theory of early development based on the recollections of childhood by his adult clients. In many ways, Freud set the agenda for the next 50 years of developmental psychology by defining content domains (aggression, sex roles, morality) and articulating central themes (the importance of early experience, the formative impact of early family relationships for later developmental outcomes).

Alfred Binet (1857–1911) was the most underappreciated figure of this era (Siegler, 1992). Despite his lack of formal training in psychology, Binet was a prolific contributor with over 200 books, articles, and reviews on a wide range of psychological subjects to his credit. Binet is, of course, best known for his contributions to the assessment of intelligence (Binet & Simon, 1905), but he was much more than the father of IQ testing. He anticipated a number of Piaget’s views, for example, that cognitive development is a constructive process, that its purpose is adaptation to the physical and social worlds, that children assimilate new experiences to existing ways of thinking, and that intelligence pervades all activities. Moreover, he made major contributions to various areas of memory, particularly suggestibility and eyewitness testimony, children’s memory for prose, and the role of memory in mental calculation expertise (Binet, 1894, 1900). Binet designed and conducted a variety of memory experiments. At the same time, he recognized the need to apply convergent methodological approaches to solve psychological problems. “Our psychology is not yet so advanced that we can limit our analyses to information attained in the laboratory” (Binet, quoted in Cairns, 1983). It is interesting that Binet’s demonstrations of the feasibility of an experimentally based science of child development predated Watson’s more famous experiments on conditioning of emotion by nearly 20 years. “Binet was the first to provide convincing evidence for the proposition that a science of human development was possible” (Cairns, 1983, p. 51). For a variety of reasons—primarily, perhaps, his lack of a university position—Binet’s contributions were largely forgotten until recently (Cairns, 1983; Siegler, 1992).

CHARACTERISTICS OF THE EARLY THEORIES IN DEVELOPMENTAL PSYCHOLOGY

Theories of development may be characterized, most centrally, by whether they posit that development is the consequence of internal (nature) or external (nurture) forces. Overton and Reese (1973) describe this dichotomy as organismic versus mechanistic. The organismic view is characterized by a focus on biological or endogenous accounts of development. It has as its basic metaphor “the organism, the living, organized system presented to experience in multiple forms. . . . In this representation, the whole is organic rather than mechanical in nature” (Reese & Overton, 1970, pp. 132–133). The mechanistic view is characterized by a focus on environmental mechanisms, and development is seen as essentially an externally controlled or driven process. The machine is often used as the metaphor for this developmental model of development. In the early era, Baldwin, Freud, Hall, and Binet all endorsed an organismic approach. As Cairns noted of Baldwin: “His aim was to outline ‘a system of genetic psychology’ that would attempt to achieve a synthesis of the current biological theory of organic adaptation with the doctrine of the infant’s development” (Baldwin, 1895, p. vii, cited by Cairns, 1983, p. 54).

Another way in which theories of development can be described is in terms of their breadth. The scope of the early theories was notably broad. Not only did they include emotions and cognitions, sex and sensation, but a century ago, theorists in the grand tradition assumed that large portions of the developmental landscape could be accounted for in terms of a limited number of general, universal principles. They were not unaware of cross-cultural variation, but they viewed other cultures as living laboratories that could provide opportunities to evaluate the operation of fundamental laws of development. Freud’s use of anthropological data in Totem & Taboo (Freud, 1918) was an attempt to describe unconscious motivation in other cultures. This was a prime example of our ancestors’ eagerness to seek confirmation of their theories in other cultures. Their understanding of those cultures, however, was quite limited.

Limited, too, was their understanding of their own culture. Contemporary developmental psychologists recognize that societal conditions in a variety of spheres—medical, education, economic, political, and social—influence both development itself and research and theory about development. They have seen how historical conditions can shape choices of problems and theoretical interpretations. The most celebrated example, of course, is the influence of Victorian Vienna on psychoanalysis (Lerner, 1986). The repressive views concerning sex and sexuality held by European society in the early 1900s quite clearly contributed to the symptoms exhibited by Freud’s patients and the focus on sexual feelings and processes in Freud’s theory. However, Freud himself and the other early theorists showed little awareness of the need to acknowledge the role of societal and historical influences in their theories of development.

As an emerging discipline, not surprisingly, developmental psychology was also an interdisciplinary enterprise. The early theorists looked to philosophy, biology, pedagogy, and sociology for ideas. Hall was particularly influenced by philosophy, religion, education, and evolutionary biology. Baldwin reached out to religion. Freud incorporated anthropology. At the same time, there was a strong push to disassociate the emerging field from its roots—especially its philosophical roots—and to establish the new field as a separate discipline, especially a scientific one. Baldwin’s theories as well as Binet’s experimental demonstrations represented clear departures from the introspectionist approach of the past.

In brief, by 1914, American psychology had become established as an independent discipline, developmental psychology as a separate science was beginning to emerge, and the major themes of development that occupied us for the next century were being defined. In the next phase, the institutionalization of developmental psychology as a distinctive subfield within mainstream psychology began.

A PERIOD OF INSTITUTIONALIZATION AND FRAGMENTATION OF DEVELOPMENTAL PSYCHOLOGY (1915–1940)

Two major themes characterize the next period in the history of developmental psychology. First, this was a period of establishment of major research institutes. Second, it was an era both of extraordinary theoretical and empirical advances in developmental psychology and of multiple voices and raucous cacophony.

THE INSTITUTES OF CHILD DEVELOPMENT

Reflecting societal concerns about ways to improve the rearing of children, a number of research institutes were established around the United States, including those at the University of Iowa, the University of Minnesota, Teachers College at Columbia, Yale, and the University of California, Berkeley. The goals of these new institutes were research, teaching, and dissemination. The programs were modeled after the successful agricultural research stations. As Mrs. Cora Bussey Hillis, an early supporter of these activities, envisioned, “if research could improve corn and hogs, it could improve children” (Sears, 1975, p. 19).

The institutes not only created a professional workforce of child developmentalists but also initiated some of the major longitudinal projects of the century. Some of these projects were highly specialized; others were more general. At Yale, Arnold Gesell (1880–1961) began his intensive studies of children’s motor development, while John Anderson at Minnesota provided detailed descriptions of personality development (Anderson, 1937). At Berkeley, two sets of longitudinal studies began in the late 1920s and early 1930s focusing on a variety of aspects of development—intellectual, social, and motor (see Bayley, 1949; Elder, 1974). Sontag (1944), at the Fels Research Institute, also started a longitudinal study in the 1930s that lasted until the 1970s. The Fels project also used a broadband approach involving assessments of social, emotional, motoric, and physical development. These studies were largely a theoretical and descriptive; they provided important normative guidelines concerning early developmental timetables.

A TRIAD OF TOWERING THEORISTS

But theory in developmental psychology was not dead. On the contrary, this was an era of fragmentation, and markedly different theoretical approaches to the study of development were all competing for support. In the United States, behaviorism under the leadership of John B. Watson (1878–1958) was a force to be reckoned with, with its strict views that children’s development was the consequence of conditioning by the environment. According to Watson, children learn everything, from skills to fears. All behavior begins as a simple reflex and is conditioned over time. Fears are most easily conditioned through pairing with loud noise; love is created by fondling; even verbal behavior and thinking begin as babbling, then grow in complexity as they are conditioned to objects in the environment. Watson’s (1913, 1924) experimental demonstrations of conditioning, most famously of little Albert, did much to place the newly emerging field of child development on a solid scientific footing.

Meanwhile, other viewpoints were emerging as significant challenges to a behavioral view of development. Most directly in opposition to Watson’s position was Gesell’s maturational approach to development, which suggested that development unfolds in a series of steps, fixed and predetermined in order. Only under extreme conditions, such as famine, war, or poverty, are children thrown off this biologically programmed timetable. According to Gesell, the tendency to grow is the strongest force in life, and the inevitableness and surety of maturation are the most impressive characteristics of early development. “The inborn tendency toward optimum development is so inveterate that [the child] benefits liberally from what is good in our practice, and suffers less than he logically should from our unenlightenment” (Gesell, 1928, p. 360). Gesell’s years of careful observation produced a corpus of work that was not only a highly sophisticated account of motor development but an early version of a dynamic systems view of development (Thelen, 1993).

At the same time, Jean Piaget (1896–1980) was emerging as an influential theorist in Europe and offered a further contrast with prevailing American views. Piaget offered not only a rich description of children’s cognitive progress from infancy to adolescence but the first fully developed theory of stages of cognitive development. In a series of books, Piaget outlined four major stages of cognitive development, the stages of sensorimotor development (0 to 2 years), preoperational development (2 to 6 years), concrete operations (6 to 12 years), and formal operations. Children were observed to pass through these stages in a fixed and sequential order as they moved toward increasingly abstract modes of thought. His theory and empirical demonstrations over the span of more than half a century place him with Freud in the forefront of child development theorists of the twentieth century. Although there have been challenges to his originality with credible claims that much of his theory was anticipated by Baldwin (Cahan, 1984), his uncanny ability to design tasks to test his theoretical propositions secured his scientific reputation.

AN APPRAISAL OF THE ERA

The marked differences among the three theorists in this period, Watson, Gesell, and Piaget, are brought into perspective by noting their positions on key developmental questions. Their basic positions concerning what causes development were in stark contrast. Watson was the archetypical mechanistic theorist who believed that development occurred from the outside in. He believed that the goal of theory was not to understand behavior but to predict and control it. He viewed learning and conditioning principles as the processes through which these ends were met. In contrast, Gesell was a theorist who was organismic in his viewpoint on the causes of development, championing maturational processes as the key to development. His goal was to provide a systematic account of development, not necessarily to control or predict the direction of development. Piaget balanced the importance of both internal, biological processes of development and external resources to support it. He posited biological adaptational processes as the explanatory mechanism for development, and his theoretical aim was understanding, not prediction or control. Although these three theorists diverged in their assessment of the nature of developmental processes, they did agree that there are universal and historically independent processes that account for development.

The three theorists also differed in their assumptions about the course of development. Piaget was clearly a committed stage theorist who endorsed the concept of discontinuity across development. Watson, on the other hand, viewed development as continuous. Gesell recognized both continuity and discontinuity across development. For Gesell, there are periods of reorganization at different points across development but considerable continuity in terms of underlying processes. Siegler and Crowley’s (1992) microgenetic approach might well have been championed by Gesell, with its recognition that there is an uneven progression across development as new skills and strategies are acquired and integrated in the child’s repertoire.

The big-three theorists of this era also took somewhat different approaches to conducting research. Watson performed laboratory “experiments,” which actually, because of their lack of control, are more accurately referred to as demonstrations. Gesell and Piaget, in contrast, raised systematic observation to a new level. Piaget watched, with much profit, his own infants (Piaget, 1926), while Gesell made a career of cataloging motor movements of other people’s children (Gesell, 1928). Both incorporated subtle structured interventions into their observations—a pile of three red blocks, a matchbox, a screen—to probe with infinite patience the minute changes in abilities evident over the course of a week or a month in a child’s life.

A final way in which the triad of theorists differed was in their view of how—or whether—the principles of developmental psychology should be applied to “real world” issues. Piaget was basically uninterested in applied issues—in spite of an abundance of efforts by others to apply his theory to education settings in the 1960s and 1970s. He called these concerns “the American question.” In contrast, Watson was a strong proponent of applying learning principles to the rearing of children. Through a series of popular books addressed to parents, Watson tried to shape the thinking of a generation of parents. “Parents, whether they know it or not,” he stated with authority, “start intensive training of their children at birth. By 3 years of age, the child’s whole emotional life plan has been laid down. His parents have determined whether he is to grow into a happy person, a whining, complaining neurotic, an overbearing slave driver, or one whose every move in life is controlled by fear.” What was most damaging, according to Watson, was too much “mother love.” Watson’s advice on how to run an efficient, no-nonsense household, in which infants were fed and napped on schedule like efficient little machines, and no time was lost nor bad habits created by hugging and kissing, had a widespread influence on American parents. In spite of his maturationalist leanings, Gesell, too, was a prolific and influential voice in the “advice to parents” movement. Over a period of 40 years, Gesell and his colleagues (Gesell & Ilg, 1946; Gesell, Ilg, & Ames, 1956) offered not only normative guidelines to help parents anticipate the developmental trajectories of their children but also specific advice concerning child-rearing tactics, toys, and tomes for children of different ages (see Clarke-Stewart, 1978, 1998). The outreach efforts of both Watson and Gesell were consistent with the tenor of the time and theAmerican belief that the new developmental science could and should be harnessed to improve the lives of children.

To summarize, this period of our history was best characterized as a battle among theoretical titans. A science of development had clearly been launched, but there was little agreement about the theoretical details.

THE ERA OF EXPANSION OF DEVELOPMENTAL PSYCHOLOGY (1940–1960)

In the third period of our history, developmental psychology returned to the fold of mainstream psychological thinking, as it had been at the turn of the century. Major strides were achieved by extending the basic tenets of learning theory to the puzzles of development.

FUSING LEARNING THEORY AND PSYCHOANALYSIS

Classic learning theory, which dominated American psychology from the 1930s through the 1950s, was creatively combined with Freud’s theory of development to generate a new era of research and theorizing in child psychology. At Yale, several young psychologists, including John Dollard, Neal Miller, Leonard Doob, Robert Sears, and later anthropologist John Whiting, combined forces to fuse Hullian learning concepts with Freudian psychoanalytic theory (e.g., Dollard, Doob, Miller, Mowrer, & Sears, 1939). Their goal was to translate Freud’s propositions into testable form by recasting them in learning-theory terms. Freud had provided the focus of the research on such issues as aggression, sex typing, and dependency; Hull provided the learning mechanisms, such as primary and secondary drives, drive reduction, and stimulus-response associations. In one example of the learning-psychoanalytic fusion, the Yale psychologists proposed that infants’ early attachment to their mother derived from the association of the mother with reduction of the hunger drive through feeding. Mothers, in short, assumed secondary reinforcement value as a result of being paired with hunger reduction for the infant. Decades of effort followed, in which these researchers sought to evaluate the relations between early child-rearing practices and later personality development. Such Freudian-based concerns as the timing of weaning and toilet training and whether the infant was bottle- or breast-fed dominated the scientific activity (Sears, 1944, 1975).

The major paradigm for this era is illustrated by the classic study of child rearing organized by Robert Sears and his colleagues Eleanor Maccoby and Harry Levin (Sears, Maccoby, & Levin, 1957). These investigators interviewed over 300 mothers about their child-rearing practices (weaning, toilet training, discipline) and the child’s behavior (aggression, dependency, sex roles, moral development). Modest relations between child-rearing practices and child outcomes were found in this and related studies (Sears, Rau, & Alpert, 1966; Sears, Whiting, Nowlis, & Sears, 1953; Whiting & Child, 1953), but the enterprise as a theoretical guide was largely unsupported. Not only were the fundamental hypotheses probably incorrect, but the methods themselves came under serious criticism (M. R. Yarrow, Campbell, & Burton, 1964). Critics noted not only that constructs were poorly defined but also that the basic method of using mothers’ recall of their earlier practices was fraught with error. As Robbins (1963) showed, mothers often report child-rearing practices that are more in agreement with current “experts” than they are with their actual practices. Although the enterprise served to bring theoretical rigor to the study of development and move us beyond description to learning-based explanations of development, the theoretical limitations of the Freudian framework were bound to doom their efforts.

AN OPERANT ORIENTATION

Another extension of learning theory that emerged during this era was operant learning theory. This approach was developed by B. F. Skinner (1904–1990) at Harvard University. In contrast to Hullian theory, with its drive-centered focus, Skinner’s theory emphasized contingent reinforcement of behavior as the central learning mechanism. Although Skinner was not a developmental theorist, his thinking had a profound impact on developmental psychology. Such influential developmental researchers as Bijou, Baer, and Gewirtz were all influenced by Skinner (Bijou & Baer, 1961; Gewirtz, 1969). The modern behavior modification approach to the control and shaping of children’s behavior in classrooms, homes, and institutional settings owes a direct debt to Skinner and his theory of operant learning.

REFLECTIONS ON THE ERA OF EXPANSION

Under the guidance of the learning titans of this era, developmentalists once again became a part of mainstream psychology. A mechanistic orientation characterized the theorizing of the period, whether under the guidance of Hullian-influenced Sears or of operant-oriented Skinner. Theorists searched for broad, universal principles of development, with little concern for either culture or secular influences, although Sears did document social-class differences in child-rearing practices in one of his studies (Sears et al., 1957). Neither Sears nor Skinner was a prominent provider of descriptions or prescriptions for parents in the tradition of Watson and Gesell, but they both had an abiding American faith in the potential of developmental science to help children. Skinner’s invention of the baby box and teaching machine and Sears’s hope that his studies of child rearing would provide scientific guidelines for future parents illustrate their commitment to an applied developmental psychology.

In sum, during this era, developmental psychology became recognized as part of mainstream psychology, but it had not yet reached a mature state. In the case of Sears, there was still too much borrowing from the past, and in the case of Skinner, there was not enough recognition of the uniqueness of children that might require distinctive and separate approaches.

THE RISE OF CONTEMPORARY THEMES IN DEVELOPMENTAL PSYCHOLOGY (1960–1985)

In the era from 1960 to 1985, a number of themes rather than a number of theorists guided research and theory in developmental psychology. These themes were the return of a concern about cognition, the discovery of precocity, the redefining of social learning, the refinement of the study of social interaction, and the emergence of an interest in emotion.

THE RETURN OF COGNITION

Several significant events transformed our thinking about development in this quarter century. The Russians launched Sputnik, and Americans began to worry about their educational system. Coincidentally, there was a rediscovery of Piaget by American psychologists. J. McVicker Hunt (1906– 1991) published his influential treatise, Intelligence and Experience (1961), which reintroduced Piagetian thinking to Americans. A few years later, a systematic overview of Piaget’s theory was offered by John Flavell in his book The Developmental Psychology of Jean Piaget (1963). Piaget’s views of nature and nurture as both necessary and interactive quickly became prevalent in developmental psychology. A flurry of empirical work that both supported and challenged Piagetian theory appeared in the 1960s and 1970s. This revitalized interest in cognitive development coincided with the onset of the cognitive revolution (Miller, Galanter, & Pribram, 1960) in mainstream psychology, so it is not surprising that cognitive development returned as a major theme of research.

THE DISCOVERY OF PRECOCITY

In part the result of Piaget’s early work on infant cognitive and perceptual development and in part the consequence of new experimental techniques for assessing infant visual, auditory, and olfactory capacities (e.g., Fantz, 1963; Lipsitt, 1963), there was a resurgence of interest in documenting infant sensory and perceptual competence. Studies of infants challenged traditional views and ushered in an era of discovering the “competent infant.” In contrast to earlier views of infants as limited, helpless, and incompetent, these new studies revealed an infant who was biologically prepared for social, perceptual, and cognitive encounters with the external environment. Babies were revealed to be capable of visual and auditory discriminations (e.g., color, form, pitch) from a much younger age than earlier theorists had assumed. In turn, this prepared the way for a closer look at biological contributions to early development. A similar set of advances concerning the remarkable capacity of infants to learn was also reported (Lipsitt, 1963; Papousek, 1961; Sameroff, 1970).

REDEFINING SOCIAL LEARNING THEORY

On the socialization front, there was a serious challenge to the Freud-Hull approach to social development. Albert Bandura and Richard Walters, in their 1963 volume Social Learning and Personality Development, forcefully rejected the assumptions of the previous era. Instead of endorsing a drive-based theory of development, they proposed that observational learning or modeling was the major way that children acquire new behaviors and modify old ones. As subsequently developed by Bandura (1969, 1977), cognitive social learning theory drew much of its theoretical foundation from developments in the new cognitive science, with its insights into attention and memory. Not only were drives and drive reduction unnecessary for learning, according to Bandura, but reinforcement was unnecessary either for the acquisition of new responses or the modification of old responses. Along with new mechanisms for learning, Bandura dismissed the Freudian baggage of the earlier Sears era. Instead, a more eclectic theory of socialization, which drew from sociology, anthropology, and other disciplines, served as a guide. In a series of influential experimental studies, Bandura and his colleagues revitalized the study of social development by reintroducing experimental approaches in studies of the observational learning of aggression (e.g., Bandura, Ross, & Ross, 1961). Unfortunately, like most learning theory approaches, the focus was more on learning and less on development (see Grusec, 1992).

FROM SOCIAL INTERACTION TO SOCIAL RELATIONSHIPS

An area of intense focus in this period was the social interactive processes and the ways in which these face-to-face processes develop into social relationships (Hartup & Rubin, 1986; Hinde, 1979). A prominent issue was the understanding of social interaction patterns among infants, children, and their social partners. Emphasis on the mutual regulation of the partners’ behavior, concern about detailed description, and quantification of the tempo and flow of the interactive interchange clearly separated the current work from its earlier antecedents (Cohn & Tronick, 1987; Field, 1991). In addition, developmental psychologists in this era went beyond studying the process of interaction per se to use interaction as a window into social relationships (Hinde, 1979).

The most influential theory exemplifying this theme was John Bowlby’s (1907–1990) theory of attachment (1969, 1973, 1980). This theory offered a new account of the ways in which infants come to form close relations with their caregivers. Instead of a fusion between the constructs of Hull and Freud, it represented a marriage between ethology and psychoanalysis. Bowlby proposed that attachment has its roots in a set of instinctual infant responses that are important for the protection and survival of the species. The infant responses of crying, smiling, sucking, clinging, and following elicit the parental care and protection that the baby needs and promote contact between the child and the parents. Just as the infant is biologically prepared to respond to the sights, sounds, and nurturance provided by caregivers, parents are biologically prepared to respond to these eliciting behaviors on the part of the infant. As a result of these biologically programmed responses, both parent and infant develop a mutual attachment. From this perspective, attachment is a relationship, not simply a set of behaviors of either the parent or the infant (Sroufe & Fleeson, 1986).

Moreover, in this era, there was an increasing appreciation of the range of characters who play a prominent role in children’s social relationships. The definition of family expanded to include not only the mother–infant dyad but fathers, siblings, and grandparents as well (Dunn & Kendrick, 1982; Lamb, 1975; Tinsley & Parke, 1984).

There was also a growing appreciation of the embeddedness of children and families in a variety of social systems outside the family, including peers, school, and kin-based networks (Bronfenbrenner, 1986, 1989; Cochran & Brassard, 1979), which led to an interest in peer and other relationships outside the family (Asher & Gottman, 1981). This focus on relationships was part of a more general reorientation away from a focus on the individual as the unit of analysis to dyadic and larger units of analysis.

EMBRACING EMOTION

One of the most dramatic shifts during this period was the renewed interest in the development of emotions in infancy. Topics such as social smiling, stranger anxiety, and fear of heights were of interest in the 1960s (Gibson & Walk, 1960), but the motivation for conducting such studies was to use emotions to index something else—usually perceptual or cognitive process (Campos & Barrett, 1985). The timing of the development of emotions and the role of emotions in social interaction were of little interest at that time. In the 1970s and 1980s, however, the role of affect became an issue of increasing concern throughout psychology (e.g., Campos, Barrett, Lamb, Goldsmith, & Stenberg, 1983). The developmental origins of both the production and recognition of emotions, as well as the role of emotional expressions in the regulation of social interaction, became central concerns of developmental psychologists, especially infancy researchers.

In light of research by Ekman (Ekman & Friesen, 1978) and Izard (1982), the older assumption that facial response patterns are not specific to discrete emotional states was discounted. Evidence suggested that facial expressions may be, at least in part, governed by genetically encoded programs and universally recognized (Ekman & Friesen, 1978). The recognition that emotional expressions have a role in the regulation of social behavior, another important development in this era, was exemplified in studies of face-to-face interaction of parents and infants (e.g., Brazelton, Koslowski, & Main, 1974; Stern, 1977, 1985; Tronick, 1989).

ADVANCES IN THEORY AND METHOD

In this period, from1960 to 1985, we see signs of maturity in the field of developmental psychology. Instead of theories suggesting that development is either exclusively internally driven or entirely environmental in origin, the theories in this period included elements of both. In addition, under the guidance of Bronfenbrenner (1979), a commitment to contextualism was evident. Lerner (1986), a major proponent of this viewpoint, defines this position as follows: A contextual model assumes that there is constant change at all levels of analysis and that each level is embedded within all others. Thus, changes in one promote changes in all. Central to the position is the interaction between the organism and its context (Sameroff, 1975). Ethology, ecological systems theory, and socio-cultural theory are examples of the contextual model.

Explanatory processes, too, were multifaceted in this period and included cognitive, social interactional, and affective processes. The grand claims of earlier eras were less evident, and more limited theories, which explained smaller bands of behavior rather than the full array of development achievements, began to emerge. A glimmer of recognition that theories may not be universally applicable appeared in this period, and interest in cross-cultural work intensified (Greenfield, 1974; Harkness & Super, 1983). The role of historical and secular changes, such as the Great Depression, as influences on development were recognized for the first time (Elder, 1974). There was a return to an interest in applying basic knowledge to practical problems of child rearing and education unseen since the days of Gesell and Watson (e.g., research on the effects of early preschool experience on children’s development by Ramey & Haskins, 1981). There was a shift toward a lifespan view of development, and, consistent with this shift, a reevaluation of the role of critical periods in development. Although considerable evidence to support the critical period hypothesis as it related to infant social development was collected (e.g., Harlow & Harlow, 1962; Sackett, 1968; L. J. Yarrow, 1961), it also became apparent in this period that simple yes-or-no questions about whether early experience played a role in particular domains were inadequate to guide our thinking. Rather, it was important to understand the processes through which experiences exerted their influence on structure and function and when they exerted that influence.

THE CURRENT PERIOD OF DEVELOPMENTAL PSYCHOLOGY (1985–PRESENT)

In the current period, several themes characterize research and theory in developmental psychology. These include the rise of interest in the genetic and neurological underpinnings of behavior, interest in the interdependency of cognition and emotion, recognition of the role of culture, and a move toward a mature interdisciplinary developmental science.

RETURN TO THE BIOLOGY OF DEVELOPMENT

Of considerable importance in the current period is the lively interest of developmental psychologists in biology. This interest has been expressed in many ways. One way is the investigation of psychophysiological responses associated with different emotions and different social situations, such as separation of a child from the mother or the entrance of a stranger into the room (Field, 1987). These studies provide additional evidence in support of the specificity-of-emotion hypothesis (i.e., that different emotions may have different elicitors and distinct psychophysiological patterns; Campos et al., 1983).

A second way the current interest in the biological bases of behavior is expressed is through the study of genetics. This return to biology resulted, in part, from advances in the field of behavior genetics, which produced a more sophisticated understanding of the potential role that genetics can play not only in the onset of certain behaviors but in the unfolding of behavior across development (Plomin, DeFries, & McLearn, 1990). This work has generally taken the form of determining the possible genetic origins of certain traits, such as extroversion and introversion, and other aspects of temperament, as well as the age of onset of emotional markers such as smiling and fear of strangers. For example, Plomin and DeFries (1985) found that identical twins exhibit greater concordance than fraternal twins in the time of onset and amount of social smiling. Similarly, identical twins are more similar than fraternal twins in social responsiveness (Plomin, 1986). At the same time, behavior genetic researchers are documenting the clear and necessary role of the environment in this process. Plomin’s (1994) reformulation of genetic questions has led to a call for studies of nonshared-environment effects and represents a good example of how behavior genetics has stimulated new designs for the assessment of both genetic and environmental influences. Rather than returning to an old-fashioned nature-nurture debate, the new behavior genetics is spurring the development of better measures of the environment that will enable us to assess the interactions of nature and nurture in more meaningful ways. Clearly, environmental influences matter; they simply need to be measured better. One of the ironies of recent years is that some of the most compelling evidence that environmental effects are important comes from behavior genetics. At the same time, advances in the measurement and conceptualization of specific environmental influences has come largely from the work of socialization scholars interested in parental disciplinary styles and socialization techniques and who generally used between-family than within-family designs (Baumrind, 1973; Radke-Yarrow & Zahn-Waxler, 1984). In fact, the reorientation of research to a nonshared emphasis remains controversial, and there is considerable debate about the implications and interpretation of nonshared effects (Baumrind, 1993; Hoffman, 1991; Scarr, 1993). Recently there has been a rise of interest in the role of molecular genetics in developmental research (Plomin & Rutter, 1998; Reiss, Neiderhiser, Hetherington, & Plomin, 2000) with the goal of identifying how specific genes or clusters of genes are linked with developmental outcomes.

Other ways that developmentalists in the current period focus on the biological bases of behavior is studying hormones and behavior during infancy and adolescence (Gunnar, 1987) and looking for the biological bases for temperament in infancy (Rothbart & Bates, 1998). They also study biological constraints on behavior development; for example, developmental implications of immature sensory systems have been related to the social world of infants (e.g., Aslin, 1998), the implication of immature limb systems have been related to locomotion (Thelen & Ulrich, 1991), and the implications of the immature cortex have been related to infant search behavior (Diamond, 1990, 1991). As these last studies indicate, recent advances in cognitive neuroscience have also begun to influence developmental psychology (Diamond, 1990; Greenough, Black, & Wallace, 1987), and this is another sign of developmental psychologists’ return to biology. Finally, the resurgence of interest in the types of evolutionary approaches to the study of human development represents a return to Darwin’s early efforts to apply evolutionary principles to human development (Bjorklund & Pellegrini, 2000; Hinde, 1991). Although controversial (Hinde, 1991), this theorizing clearly illustrates one of the myriad ways in which psychologists are returning to questions that were raised by our forebears.

DEEPENING THE STUDY OF COGNITIVE DEVELOPMENT

As part of the current vigorous study of cognitive development, researchers have returned to issues of consciousness, reflection, intention, motivation, and will (Flavell, 1999). There has been a reemergence of interest in the interplay between conscious and unconscious processes, an indication of a willingness to tackle problems that preoccupied our field’s founders but were set aside for nearly a century. Several investigators (Greenwald, 1992; Kihlstrom, Barnhardt, & Tataryn, 1992) have developed methods that permit examination of the impact of unconscious processes on a variety of cognitive and perceptual processes and allow methodologically defensible excursions into such classic clinical issues as repression and self-deception. These methods could be adapted usefully for developmental studies and would provide interesting approaches to a range of current issues, from eyewitness testimony to early affective memories. In turn, such applications would have important implications for an understanding of effects of early experience and attachment.

There is also a strong interest in the interplay between cognition and emotion, as reflected in the activity surrounding children’s understanding of emotion (Harris, 1989; Saarni, 1999). Most recently, the range of emotions under investigation has expanded to include self-conscious emotions such as shame, guilt, pride, empathy, and envy, topics that were anticipated by Freud and others but were of little interest for many years (Denham, 1998; Eisenberg, 1991; Lewis, 1992).

APPRECIATION OF THE ROLE OF CULTURE IN DEVELOPMENT

One of the major shifts in our thinking about development in the current era is our recognition of the central role played by culture. Since the 1980s, more attention has been given to contributions of culture to our theoretical explanations of development (e.g., Gauvain, 2001; Rogoff, 1990). One example is the cross-cultural studies of infant–parent attachment, in which wide disparities were found in the distribution of infants in terms of their attachment classifications. Although the measures show securely attached infant–mother relations in 57% of American samples, the rate drops to 33% in samples tested in northern Germany (Grossman, Grossman, Spangler, Suess, & Unzner, 1985). These and other findings underscore the need to consider cultural influences in our developmental theories.

Similarly, there have been advances, albeit limited, in our understanding of intracultural and socioeconomic differences in the United States (Parke & Buriel, 1998). Although African American children have received the most attention, other groups, including Latino and Asian American children, are beginning to be more commonly included in developmental investigations (McLoyd, Cauce, Takeuchi, & Wilson, 2000; Steinberg, Dornbusch, & Brown, 1992). These variations across ethnic lines represent important opportunities to explore the universality of psychological processes and to provide naturally occurring variations in the relative salience of key determinants of social, emotional, and cognitive development. These studies may provide a better basis for guiding policies, programs, and culturally sensitive interventions on behalf of children. As our culture becomes increasingly diverse, it is important that we begin to make a serious commitment to an exploration of this diversity, both theoretically and through systematic empirical inquiry. The search for a balance between processes that are universal and those that are particular to racial, and ethnic, and socioeconomic groups probably represents one of the greatest challenges of the new century.

APPRAISAL OF THE CURRENT ERA

The current era represents significant continuity with the prior period and can best be characterized as eclectic in terms of theoretical models, developmental assumptions, and methodological approaches. As is characteristic of a more mature science, methods and models are not perceived as dogmatic dicta but instead are flexible guides to help formulate and answer new questions and address new issues as they arise.

The retreat from grand theory that began in the 1980s has continued, and in its place, a variety of minitheories aimed at limited and specific aspects of development has emerged. However, there is evidence of an attempt to link together these minitheories. The idea of general processes as explanations of development has been given up because we have learned that they are not so general; instead, it is increasingly evident that processes depend on the specifics of the situation, the task, and the subjects’ understanding of the task or situation (Flavell, 1985, 1999; Siegler, 1991). It is now recognized that the domains of childhood—social, emotional, physical, and cognitive—are interdependent and that they overlap and influence each other mutually.

Attention to secular trends and historical contexts has accelerated as the social contexts of children’s lives come under increased scrutiny (Elder, Modell, & Parke, 1994). Shifts in medical practices, employment patterns, and child-care arrangements are all issues of lively debate and vigorous research activity (Clarke-Stewart, 1992a, 1992b; Conger & Elder, 1994). Moreover, researchers are giving serious consideration to the role that shifts in technology (e.g., computers) have on children’s development; part of the puzzle is to determine whether secular trends produce changes in the timing of onset of developmental phenomena or whether developmental processes themselves are significantly altered. Current thinking suggests that certain behavioral characteristics are relatively independent of historical variations, while others are more susceptible to these influences (Horowitz, 1987).

Collaboration between disciplines is increasingly common as the multidetermined nature of development is increasingly appreciated. Not only are sociologists, anthropologists, and historians part of new developmental research teams, but so are neurologists, geneticists, lawyers, and epidemiologists. It is likely that the interesting issues and questions of the new century will arise at the boundaries between disciplines. The dichotomy between applied and basic research is fading rapidly, and child developmentalists are returning in increasingly large numbers to their applied roots. For example, research on mental-health issues among children is prominent, and work on how to improve children’s early development through intervention programs continues to flourish (Coie & Jacobs, 1993).

In terms of developmental assumptions, developmentalists have become less interested in strong forms of discontinuity organized around stage constructs. Rather, there is growing recognition that the course of development may vary markedly even for presumably related concepts. But there is also recognition that the entire issues of qualitative or quantitative change may depend on one’s point of observation. As Siegler indicated, “When viewed from afar, many changes in children’s thinking appear discontinuous; when viewed from close-up, the same changes often appear as part of a continuous, gradual progression” (1991, p. 50).

Researchers in the 1980s and 1990s have taken seriously a life-span developmental perspective (Baltes, 1987). In part, this view emerges from a recognition that the social context provided by caregivers varies as a function of the location of the adults along their own life-course trajectory (Parke, 1988). The earlier view was that variations in parenting behavior were relatively independent of adult development. Evidence of this shift comes from a variety of sources, including studies of the impact of the timing of parenthood and the effects of maternal (and paternal) employment, job satisfaction, and work involvement on children’s development (Parke & Buriel, 1998). In addition, there is a serious return to the study of aging (Baltes, 1987; Salthouse, 1985), especially the study of speed of processing, memory, and intelligence (e.g., Hertzog, 1989) and social behavior (e.g., Brubaker, 1990; Hanson & Carpenter, 1994).

Consistent with the shift toward a life-span view is the reevaluation of the role of critical periods in development. Recent evidence suggests that a modified version of sensitive, if not critical, periods is likely to emerge in contrast to a view of unlimited plasticity across development (Bornstein, 1989). For example, Rieser, Hill, Talor, Bradfield, and Rosen (1992) have demonstrated that adult skill in spatial representation seems to require early perceptual learning experiences that involve self-produced movement. Johnson and Newport (1989) found evidence for a sensitive period in grammatical mastery in acquiring a second language. The question for this century is to discover which aspects of behavior are likely to be altered by environmental events at specific points in development and which aspects remain more plastic and open to influence across wide spans of development.

In terms of units of analysis, researchers have begun to conceptualize the unit of analysis as dyads within the family system, such as the parent–child dyad, the husband–wife dyad, and the sibling dyad (Belsky, 1984; Cowan & McHale, 1996; Parke, 1988). Moreover, units beyond the dyad have been recognized as important as well. Several researchers have recently begun to investigate triads (Hinde & Stevenson Hinde, 1988; Kreppner, 1988) as well as the family as units of analysis (Dickstein et al., 1998).

At present, this shift toward units beyond the individual is evident in cognitive as well as social development and is due, in part, to the revival of interest in Vygotskian theory. Lev Vygotsky (1896–1934), a Russian psychologist, championed the view that mental functioning is a kind of action that may be exercised by individuals or by dyads or larger groups (Wertsch, 1991). His view was one in which mind is understood as “extending beyond the skin.” “Mind, cognition and memory . . . are understood not as attributes or properties of individuals but as functions that may be carried out intermentally or intramentally” (Wertsch & Tulviste, 1992, p. 549). Such terms as socially shared cognition (Resnick, Levine, & Teasley, 1991), socially distributed cognition (Hutchins, 1991), and collaborative problem solving (Rogoff, 1990) reflect the increasing awareness that cognition can be a social as well as an individual enterprise.

In terms of methods, variety best describes the contemporary period. In the 1990s, the use of longitudinal designs increased markedly, motivated in part by an increased interest in issues of developmental stability and change. Two types of longitudinal studies are evident. Short-term longitudinal studies, in which a particular issue is traced over a short time period of a few months to a year, are currently popular (Clarke-Stewart, Gruber, & Fitzgerald, 1994; Hetherington & Clingempeel, 1992). These studies are of value for detecting short-term stability or for tracking development across a time period of assumed rapid change in an emerging developmental process or structure.

Other longitudinal studies have a long-term character and have continued from infancy through childhood and into adolescence. For example, a number of investigators have followed families from infancy to the preadolescent or adolescent years (Sameroff, 1994; Sroufe, 1996). This strategy has permitted a more definitive evaluation of a variety of theoretical issues, especially those concerning the effect of early experience, including the role of sensitive and critical periods on later development. Nonetheless, because of the expense and difficulty of longitudinal research, cross-sectional designs still predominate among developmental investigations. Often researchers will use both strategies, and, in an area that is not yet well developed either theoretically or empirically, cross-sectional studies often precede longitudinal pursuit of an issue. A commitment to multiple design strategies rather than a near-exclusive reliance on a single design is characteristic of the current area.

In terms of experimental designs, a greater openness to multiple strategies is evident. Laboratory-based experimental studies and field-based experimental investigations coexist with nonexperimental observational field studies. Data-collection strategies come in a variety of forms as well. In spite of its less than stellar history, the self-report measure has reentered our methodological repertoire; parent, teacher, and peer reports are now commonly used. Another noteworthy trend reflects in part the openness of researchers to multimethod strategies as opposed to strict adherence to one approach. Observational methods are widely used along with verbal reports. Evidence, not just speculation, may be driving the field to this new openness to a wide range of methods. Some researchers have found that ratings of behavior yield better prediction of later social behavior (Bakeman & Brown, 1980) and later cognitive assessments (Jay & Farran, 1981) than do more microanalytic and more expensive measures of parent–child interaction.

Finally, our sampling methods have come of age. Shifts in awareness of the importance of sampling have led to an increase in use of large representative national samples in developmental research. Although this has typically been the domain of sociologists and survey researchers, in the early 1990s, developmentalists have shown an increased awareness of the potential value of supplementing their usual small-sample strategies with these large-sample approaches. One prominent example is the use of the National Longitudinal Study of Youth (NLSY) for the examination of developmental issues, including divorce, achievement, and day care (Brooks-Gunn, Phelps, & Elder, 1991). These surveys have several advantages, including a large number of subjects, more representative samples, a multifaceted range of variables, and longitudinal designs. In turn, these characteristics permit testing of more complex models of development that require large numbers of subjects. In addition, these studies allow examination of connections across content-based domains as well as encouraging interdisciplinary cooperation. Finally, they permit testing of the cultural generality of the models.

Newer, more innovative approaches that combine levels of sampling are becoming increasingly common as well. As a supplement to a large-scale survey approach, researchers are selecting subsamples of subjects for more intensive examination of a particular process of interest. For example, Beitel and Parke (1998) conducted a survey of 300 families to assess maternal attitudes toward father involvement in infant care. To supplement this approach, in which a self-report questionnaire was used, a subsample of 40 families was observed in their homes as a way of validating the self-report data. Similarly, Reiss et al. (2000) generated a nationally representative sample of stepfamilies, and in a second stage of their work, they observed these families in interaction tasks in the home. These combined approaches increase the generalizability of findings and, at the same time, allow us to illuminate basic social processes.

THE FUTURE OF DEVELOPMENTAL PSYCHOLOGY

Where are we going next? Today, a proliferation of minitheories has replaced single dominant positions or theoretical frameworks, and each of these smaller-scale theories accounts for a limited set of issues. This domain-specific nature of theory is one of the hallmarks of our current state of the field. It represents a disenchantment with grand theories both of a century ago and of our more recent past. Part of the reason for the current proliferation of smaller and more modest paradigms is the lack of a new overarching paradigm to replace the disfavored grand theories.

The next stage of our development as a field involves the creation of such a new overarching paradigm or framework to help us with our integrative efforts. There are signs that a new integration may be emerging in the form of a systems perspective that will bring together biological, social, cognitive, and emotional minitheories into a more coherent framework (Fogel & Thelen, 1987; Sameroff, 1994). Although the promise of a general dynamic systems theory is appealing and has been applied with considerable success to the motor development domain, especially by Thelen (1989), it remains to be seen whether the stringent requirements of this approach for precise parameter estimation and measurement can be met in other domains (Aslin, 1993). Whether we have reached the stage of being able to quantify social behavior or children’s theories of mind with sufficient precision to make this approach useful, beyond being merely metaphoric, is an open question.

We are cautiously optimistic that a systems approach is a promising one and has proven useful both in organizing data and in pointing to new research directions in recent family research, as well as in research on the organization and functioning of social contexts. Perhaps we need to develop a family of systems-theory integrations that would be hierarchically organized and would represent the levels of analysis that are intrinsic to different areas of development, just as we have long recognized that biological, biochemical, and social levels of inquiry may each have its own set of integrative principles (Sameroff, 1994). Multiple integrative approaches may be needed to cover different parts of the development terrain. The goal is to retain the advances that our retreat to minitheories has brought but, at the same time, to begin to put the “whole child” back together again. Our forebears had the vision to see this as the goal, and we should be in a better position to achieve it now than they were a century ago.

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