Developmental Psychology Theories

Human beings, and their families, communities, and societies develop; they show systematic and successive changes over time. These changes are interdependent. Changes within one level of organization, for example, developmental changes in personality or cognition within the individual, are reciprocally related to developmental changes within other levels. for example, changes in caregiving patterns or spousal relationships within the familial level of organization (Lewis & Rosenblum, 1974).

Moreover, the reciprocal changes among levels of organization are both products and producers of the reciprocal changes within levels. For example, over time, parents’ manner of behavior and of rearing influence children’s personality and cognitive functioning and development; in turn, the interactions between personality and cognition constitute an emergent characteristic of human individuality that affects parental behaviors and the quality of family life.

These interrelations illustrate the integration of changes within and among the multiple levels of organization comprising the ecology of human life. Human development within this ecology involves organized and successive changes—that is, systematic changes—in the structure and function of inter-level relations over time. In other words, the human development system involves the integration, or “fusion” (Tobach & Green-berg. 1984), of changing relations among the multiple levels of organization that comprise the ecology of human behavior and development. These levels include biology, culture, and history.

Given that human development is the outcome of changes in this developmental system, then, for individual ontogeny, the essential process of development involves changing relations between the developing person and his or her changing context. Similarly, for any unit of analysis with the system (for example, for the family, studied over its life cycle. or the classroom, studied over the course of a school year), the same developmental process exists. In other words, development involves changing relations between that unit and variables from the other levels of organization within the human development system. Accordingly, the concept of development is a relational one. Development is a concept denoting systemic changes—that is, organized, successive, multilevel, and integrated changes—across the course of life of an individual (or other unit of analysis).

A focus on process, and particularly on the process involved in the changing relations between individuals and their contexts, is the predominant conceptual frame for research in the study of human development in the early twenty-first century. Previously, theories about human development often involved causal splits between nature and nurture (Gottlieb, 1997: Overton, 1998). These theories emphasized either predetermined organismic bases of development, for instance, as in attachment theory (Bowlby, 1969), ethological theory (Lorenz, 1965), behavioral genetics (Plomin, 1986), psychoanalytic theory (Freud, 1949), and neo-psychoanalytic theory (A. Freud, 1969; Erikson, 1959), or environmental, reductionistic, and mechanistic bases of behavior and behavior change (Bijou & Baer, 1961).

Other theories stressed more of an interaction between organismic and environmental sources of development (Piaget, 1970). Nevertheless, there remained in the discipline a presupposition that there were two distinct sources of development. that is, that there was a split between organism and environment. As such, it was the role of theory to explain the contributions of these two separate domains of reality to human development (Overton, 1998).

The stress in contemporary theories, however, is on a “healing” of the nature/nurture split (Gottlieb, 1997), and on accounting for how the integrated developmental system functions, that is, for understanding probabilistic epigenesis. Gottlieb defined this process as being characterized by an increase of complexity or organization—that is, the emergence of new structural and functional properties and competencies—at all levels of analysis (molecular, subcellular, cellular, organismic) as a consequence of horizontal and vertical co-actions among its parts, including organism-environment co-actions. (1997, p. 90)

As such, the forefront of contemporary developmental theory and research is represented by theories of process, of how structures function and how functions are structured over time. For example, most contemporary research about human development is associated with theoretical ideas stressing that the dynamics of individual-context relations provide the bases of behavior and developmental change. Indeed. even models that try to separate biological or, more particularly, genetic, influences on an individual’s development from contextual ones are at pains to (retro)it their approach into a more dynamic systems perspective (Ford & Lerner, 1992; Thelen & Smith, 1994).

Four Dimensions

Thus, in emphasizing that systematic and successive change (that is, development) is associated with alterations in the dynamic relations among structures from multiple levels of organization, the scope of contemporary developmental theory and research is not limited by a unidimensional portrayal of the developing person (for example, the person seen from the vantage point of only cognitions, or emotions, or stimulus-response connections, or genetic imperatives). Contemporary developmental theory consists of four interrelated dimensions.

Change and Relative Plasticity

Contemporary theories stress that the focus of developmental understanding must be on systematic change (Ford & Ler­ner, 1992). This focus is required because of the belief that the potential for change exists across the life span (Baltes, 1987). Although it is also assumed that systematic change is not limitless (for example. it is constrained by both past developments and by contemporary contextual conditions), contemporary theories stress that “relative plasticity” exists across life— although the magnitude of this plasticity may vary across ontogeny.

There are important implications of relative plasticity for the application of developmental science. For instance, the presence of relative plasticity legitimates a proactive search across the life span for characteristics of people and of their contexts that, together, can influence the design of policies and programs promoting positive development (Fisher & Lerner, 1994).

Relationism and the Integration of Levels of Organization

Contemporary theories stress that the bases for change, and for both plasticity and constraints in development, lie in the relations that exist among the multiple levels of organization that comprise the substance of human life (Ford & Lerner, 1992; Schneirla, 1957; Tobach, 1981). These levels range from the inner biological level. through the individual psychological level and the proximal social relational level (involving dyads, peer groups, and nuclear families), to the sociocultural level (including key macro-institutions such as educational, governmental. and economic systems) and the natural and designed physical ecologies of human development (Bronfenbrenner. 1979: Riegel, 1975). These levels are structurally and functionally integrated, thus requiring a systems view of the levels involved in human development (Ford & Lerner, 1992; Sameroff, 1983: Thelen & Smith. 1994).

Developmental contextualism is one instance of such a developmental systems perspective. Developmental contextualism promotes a relational unit of analysis as a requisite for developmental analysis: variables associated with any level of organization exist (are structured) in relation to variables from other levels; the qualitative and quantitative dimensions of the function of any variable are shaped as well by the relations that variable has with variables from other levels. Unilevel units of analysis (or the components of, or elements in. a relation) are not an adequate target of developmental analysis; rather, the relation itself—the interlevel linkage—should be the focus of such analysis (Riegel, 1975).

Relationism and integration have a clear implication for unilevel theories: of development. At best, such theories are severely limited, and inevitably provide a non-veridical depiction of development, because of their focus on what are essentially main effects embedded in higher-order interactions (Walsten. 1990); at worst, such theories are neither valid nor useful. Accordingly neither biogenic theories, for example, genetic reductionistic conceptions such as behavioral genetics or sociobiology (Freedman. 1979; Plomin. 1986); psychogenic theories, for example, behavioristic or functional analysis models (Bijou & Baer. 1961); nor sociogenic theories, for example, “social mold” conceptions of socialization (Homans, 1961; Hartup, 1978) provide adequate theoretical frames for understanding human development. Simply, neither nature nor nurture theories provide adequate conceptualizations of human development (Gottlieb, 1997). For instance. theories that stress critical periods of development (Bowlby, 1969; Erikson, 1959; Lorenz, 1965), that is, periods of ontogeny constrained by biology (for example. by genetics or by maturation) are seen from the perspective of theories that stress relationism and integration as conceptually flawed (and empirically counterfactual).

Moreover, many nature/nurture interaction theories also fall short in this regard: theories of this type often treat nature and nurture variables as separable entities and view their connection in manners analogous to the interaction term in an analysis of variance (Bijou & Baer, 196 l: Erikson, 1959; Plomin, 1986; Walsten, 1990). The cutting edge of contemporary theory moves beyond the simplistic division of sources of development into nature-related and nurture-related variables or processes: instead the multiple levels of organization that exist within the ecology of human development are seen as part of an inextricably fused developmental system.

Historical Embeddedness and Temporality

The relational units of analysis of concern in contemporary theories are understood as change units. The change component of these units derives from the ideas that all of the above-noted levels of organization involved in human development are embedded in history, that is, they are integrated with historical change (Elder, Modell, & Parke. 1993). Relationism and integration mean that no level of organization functions as a consequence of its own, isolated activity (Tobach, 1981). Each level function as a consequence of its fusion (its structural integration) with other levels. History is a level of organization that is fused with all other levels. This linkage means that change is a necessary, an inevitable, feature of variables from all levels of organization (Baltes, 1987): in addition, it means that the structure, as well as the function, of variables changes over time.

Indeed, at the biological level of organization, one prime set of structural changes across history is subsumed under the theory of evolution: evolution can be applied also to functional changes (Darwin, 1872: Got­tlieb, 1997). In turn, at more macro levels of organization many of the historically linked changes in social and cultural institutions or products are evaluated in the context of discussions of the concept of progress (Nisbet, 1980). The continuity of change that constitutes history can lead to both intraindividual (or more generally, intralevel) continuity or discontinuity in development—depending on the rate, scope, and particular substantive component of the developmental system at which change is measured (Brim & Kagan, 1980). Thus, continuity at one level of analysis may be coupled with discontinuity at another level: quantitative continuity or discontinuity may be coupled with qualitative continuity or discontinuity within and across levels; and continuity or discontinuity can exist in regard to both the processes involved in (or the “explanations” of) developmental change and in the features, depictions, or outcomes (that is. the “descriptions”) of these processes.

These patterns of within-person change pertinent to continuity and discontinuity can result in either constancy or variation in the rates at which different individuals develop in regard to a particular substantive domain of development. Thus, any pattern of intraindividual change can be combined with any instance of inter-individual differences in within-person change, that is, with any pattern of stability or instability. In other words, continuity-discontinuity is a dimension of intraindividual change and is distinct from, and independent of, stability-instability—which involves between-person change and is, therefore, a group, and not an individual concept (Baltes, 1987; Lerner, 1986).

In sum, since historical change is continuous, temporality is infused in all levels of organization. This infusion may be associated with different patterns of continuity and discontinuity across people. The potential array of such patterns has implications for understanding the importance of human diversity.

The Limits of Generalizability, Diversity, and Individual Differences

The temporality of the changing relations among levels of organization means that changes that are seen within one historical period (or time of measurement), and/or with one set of instances of variables from the multiple levels of the ecology of human development, may not be seen at other points in time (Baltes, 1987; Bronfenbrenner, 1979). What is seen in one data set is only an instance of what does or what could exist. Accordingly, contemporary theories focus on diversity—of people, of relations, of settings, and of times of measurement.

Individual differences within and across all levels of organization are seen as having core, substantive significance in the understanding of human development (Baltes, 1987; Lerner, 1998). Diversity is the exemplary illustration of the presence of relative plasticity in human development. Diversity is also the best evidence that exists of the potential for change in the states and conditions of human life (Brim & Kagan, 1980).

Moreover, the individual structural and functional characteristics of a person constitute an important source of his or her development. The individuality of each person promotes variation in the fusions he or she has with the levels of organization within which the person is embedded. For instance, the distinct actions or physical features of a person promote differential actions (or reactions) in others toward him or her. These differential actions, which constitute feedback to the person, shape at least in part further change in the person’s characteristics of individuality (Lerner, 1986; Schneirla, 1957). For example, the changing match, congruence, or goodness-of-it between the developmental characteristics of the person and of his or her context provide a basis for consonance or dissonance in the ecological milieu of the person; the dynamic nature of this interaction constitutes a source of variation in positive and negative outcomes of developmental change (Thomas & Chess, 1977).

Methodological Implications

The temporality involved in contemporary theories of human development necessitates change-sensitive measures of structure and function and change-sensitive (that is. longitudinal) designs (Baltes, 1987; Brim & Ka­gan, 1980). The key question vis-a-vis temporality in such research is not whether change occurs: rather, the question is whether the changes that do occur make a difference for a given developmental outcome.

Moreover, given that the study of these changes will involve appraisal of both quantitative and qualitative features of change, which may occur at multiple levels of organization, there is a need to use both quantitative and qualitative data collection and analysis methods. In essence, then, the concepts of historical embeddedness and temporality indicate that a program of developmental research adequate to address the relational, integrated, embedded, and temporal changes involved in human life must involve multiple occasions, methods, levels, variables, and cohorts (Schaie, 1965).

Empirical appraisals of cross-time variation and co­variation are more veridical with the character of change phenomena. Moreover, such analyses would afford examination of whether changes are consistent with theoretical propositions about developmental processes. In other words, to study any process and, more basically, to study any change phenomenon, cross-temporal (multi-occasion) data must be gathered, and it would be both theoretically interesting and important and empirically useful to recast many extant cross-sectional data as longitudinal investigations.

Indeed, change-sensitive (that is, longitudinal) designs must be used in research that is intended to appraise adequately the alterations over time that are associated with individual behavior across the life span. As noted, these designs must involve the use of measures that are developed to be able to detect change; however. it is typically the case that measures of traits are not developed to be sensitive to developmental change. Furthermore, multivariate measurement models must be used to appraise the several individual and contextual levels integrated within and across developmental periods.

However, a dynamic, systems theory, such as developmental contextualism, would move the study of human development beyond just the point of promoting multivariate-longitudinal designs involving change-sensitive measures. In addition, developmental contextualism would lead scholars to design research studies that involve:

  1. dynamic (fused) relations among levels of organization (Ford & Lerner, 1992; Tobach & Greenberg, 1984) involved in the ecology of human development;
  2. the appraisal of levels ranging from the inner-biological, and individual-psychological. to the physical ecological, the sociocultural, and the historical, and concepts that stress the ways in which levels interrelate. or are fused—such as the “goodness of fit” notion (Thomas & Chess, 1977)—may be particularly helpful;
  3. the individual differences (the diversity) that derive from variation (for example. in the timing) of the interactions among levels; and
  4. as necessary, a “co-learning” model for the design of research (and intervention) programs, which would rely on the contributions of individuals themselves to further knowledge about the issues, assets, and risks affecting their lives.

Such research thus diminishes problems of “alienation” between researchers and participants (Riegel, 1975) and suggests that any quantitative appraisal of human development rests on a qualitative understanding of their life spaces and meaning systems. Since such understanding is shaped at least in part by the participants’ input, research, and especially programs derived from such information, is more likely to be efficacious for the participants.

Thus, developmental contextualism underscores the need for policies and programs that are derived from research to be diversity sensitive and to take a change-oriented, multilevel, integrated, and developmental systems approach (Ford & Lerner, 1992), The integrated nature of this system means that change can be effected by entering the system at any one of several levels or at several levels simultaneously—depending on the precise circumstances within which one is working and on the availability of multidisciplinary and multi-professional resources.


Theoretical views such as developmental contextualism not only provide an agenda for a developmental, dynamic, and systems approach to research about human development but also allow for the promotion of positive developmental trajectories in people. When actualized, developmental systems, along with policies and programs, can ensure a continuous social support system across the life course. Such a system would be a network encompassing the familial, community, institutional, and cultural components of the ecology that impacts a person’s behavior and development across his or her life (Bronfenbrenner, 1979),

There is growing recognition that traditional and artificial distinctions between science and service and between knowledge generation and knowledge application and practice need to be reconceptualized. Scholars, practitioners, and policy makers are increasingly recognizing the important role that developmental science can play in stemming the tide of insults to the quality of life caused by poverty, premature births, school failure, child abuse, crime, adolescent pregnancy, substance abuse, unemployment, welfare dependency, discrimination, ethnic conflict, and inadequate health and social resources.

Research designs that examine topics of immediate social concern, that consider both normative and atypical developmental pathways as means of promoting and enhancing human welfare, that take into account the contextual nature of development and employ ecologically valid means of assessing functioning, and that are sensitive to the ethical dimensions of action research are required if science is to make a difference in the life of the community. Without such research, the knowledge produced by developmental scientists risks being ignored or misused by practitioners, educators, policy makers, and the public itself.


  1. Baltes, P. B. (1987) Theoretical propositions of life-span developmental psychology: On the dynamics between growth and decline. Developmental Psychology, 23, 611-­626.
  2. Bijou, S. W. & Baer. D. M. (Ed.). (1961). Child development: A systematic and empirical theory. New York: Appleton-Century-Crofts.
  3. Bowlby, J. (1969). Attachment and loss: Vol. 1. Attachment. New York: Basic Books.
  4. Brim, O. G., Jr., & Kagan. J. (Ed.). (1980). Constancy and change in human development. Cambridge. MA: Harvard University Press.
  5. Bronfenbrenner, U. (1979). The ecology of human development. Cambridge. MA: Harvard University Press.
  6. Cairns, R. B. (1998). The making of developmental psychology. In W. Damon (Series Ed.) & R. M. Lerner (Vol. Ed.). The handbook of child psychology: Vol. 1. Theoretical models of human development. (5th ed.. pp. 25-106). New York: Wiley.
  7. Darwin, C. (1872). The expression of emotion in men and animals. London: J. Murray.
  8. Elder, G. H., Jr., Modell, J., & Parke, R. D. (1993). Studying children in a changing world. In G. H. J. Elder. J. Modell, & R. D. Parke (Eds.). Children in time and place: Developmental and historical insights (pp. 3-21). New York: Cambridge University Press.
  9. Erikson, E. H. (1959). Identity and the life-cycle. Psychological Issues, 1, 18-164.
  10. Fisher, C. B.. & Lerner. R. M. (Eds.). (1994). Applied developmental psychology. New York: McGraw-Hill.
  11. Ford, D. L.. & Lerner, R. M. (1992). Developmental systems theory: An integrative approach. Newbury Park. CA: Sage.
  12. Freedman, D. G. (1979). Human sociobiology: A holistic approach. New York: Free Press.
  13. Freud, A. (1969). Adolescence as a developmental disturbance. In G. Caplan & S. Lebovier (Eds.). Adolescence (pp. 5-10). New York: Basic Books.
  14. Freud, S. (1949). Outline of psychoanalysis. New York: Nor­ton.
  15. Gottlieb, G. (1997). Synthesizing nature-nurture: Prenatal roots of instinctive behavior. Mahwah. NJ: Erlbaum.
  16. Hartup, W. W. (1978). Perspectives on child and family interaction: Past. present. and future. In R. M. Lerner & G. B. Spanier (Eds.). Child influences on marital and family interaction: A life-span perspective (pp. 23-45). New York: Academic Press.
  17. Homans, G. C. (1961). Social behavior: Its elementary forms. New York: Harcourt. Brace. & World.
  18. Lerner, R. M. (1986). Concepts and theories of human development (2nd ed.). New York: Random House.
  19. Lerner, R. M. (1998). Theories of human development: Contemporary perspectives. In W. Damon (Series Ed.) & R. M. Lerner (Vol. Ed.). The handbook of child psychology: Vol. 1. Theoretical models of human development. (5th ed.. pp. 1-24). New York: Wiley.
  20. Lewin, K. (1943). Psychology and the process of group living. Journal of Social Psychology, 17, 113-131.
  21. Lewis, M.. & Rosenblum, L. A. (Ed.). (1974). The effect of the infant on its caregivers. New York: Wiley.
  22. Lewontin, R. C.. Rose. S.. & Kamin. L. ). (1984). Not in our genes: Biology, ideology, and human nature. New York: Pantheon.
  23. Lorenz, K. (1965). Evolution and modification of behavior. Chicago: University of Chicago Press.
  24. Nisbet, R. A. (1980). History of the idea of progress. New York: Basic Books.
  25. Overton, W. F. (1998). Developmental psychology: Philosophy, concepts, and methodology. In W. Damon (Series Ed.) & R. M. Lerner (Vol. Ed.). The handbook of child psychology: Vol. 1. Theoretical models of human development (5th ed.. pp. 107-189). New York: Wiley.
  26. Piaget, J. (1970). Piaget’s theory. In P. H. Mussen (Ed.), Carmichael’s manual of child psychology (pp. 703-732). New York: Wiley.
  27. Plomin, R. (1986). Development, genetics. and psychology. Hillsdale. NJ: Erlbaum.
  28. Riegel, K. F. (1975). Toward a dialectical theory of development. Human Development, 18, 50-64.
  29. Sameroff, A. J. (1983). Developmental systems: Contexts and evolution. In W. Kessen (Ed.). Handbook of child psychology: Vol. 1. History, theory. and methods (pp. 237­-294). New York: Wiley.
  30. Schaie, K. W. (1965). A general model for the study of developmental problems. Psychological Bulletin, 64, 92­107.
  31. Schneirla, T. C. (1957). The concept of development in comparative psychology. In D. B. Harris (Ed.), The concept of development (pp. 78-108). Minneapolis. MN: University of Minnesota Press.
  32. Thelen, E., & Smith. L. B. (1994). A dynamic systems approach to the development of cognition and action. Cam­bridge, MA: MIT Press.
  33. Thomas, A., & Chess. S. (1977). Temperament and development. New York: Brunner/Mazel.
  34. Tobach, E. (1981). Evolutionary aspects of the activity of the organism and its development. In R. M. Lerner & N. A. Busch-Rossnagel (Eds.). Individuals as producers of their development: A life-span perspective (pp. 37-68). New York: Academic.
  35. Tobach, E., & Greenberg, G. (1984). The significance of t. C. Schneirla’s contribution to the concept of levels of integration. In G. Greenberg & E. Tobach (Eds.), Behavioral evolution and integrative levels (pp. 1-7). Hillsdale, NJ: Erlbaum.
  36. Walsten, D. (1990). Insensitivity of the analysis of variance to heredity-environment interaction. Behavioral and Brain Sciences, 13. 109-120.

Back to Developmental Psychology