• Developmental systems theorists argue

– Genetic and environmental factors are fused in development

– There are bidirectional influences between genetic/biological factors within the individual and all levels of the environment

Developmental Systems Theories

• Process of development involves bidirectional relations occurring over time across multiple levels of organization

– Levels of organization include those within the individual (e.g., biological) and outside the individual (e.g., societal, cultural)

– Levels are “fused” or integrated in development

• General Characteristics:

– Relative Plasticity of Development

• Potential for systematic change exists across the lifespan

• Change can be effected by entering the developmental system at any of its levels

• Change is constrained by past development and current contextual conditions (therefore relative)

– Integration or fusion of multiple levels of organization involved in development

• The appropriate unit of analysis is “relational”—relations between variables at different levels of organization, rather than variables at a single level

• Contrasts with “unilevel” models of development (e.g., nature OR nurture)

– Development within a historical/temporal context

• History = Change over time

• History is a level of organization that is fused/integrated with all other levels

– Thus, variables from all levels of organization undergo change over time

• Requires measures and designs that are “change-sensitive”– Longitudinal designs

– Multiple cohorts

– Focus on diversity in development

• Changes that are seen within one historical period (or time of measurement) and with one set of variables may not be seen at other points in time

• Research should utilize diverse samples, diverse methodologies, and multiple measurements over time

Bronfenbrenner’s Bioecological Theory

• Development of an individual occurs within a set of nested contexts or levels

• The individual and his/her characteristics is at the center of these levels– Individual characteristics include gender,

temperament, and other biologically based characteristics

Figure 9.4 The bioecological modelSiegler, DeLoache and Eisenberg: How Children Develop, Second EditionCopyright © 2006 by Worth Publishers

• Microsystem: The immediate environments that a child directly experiences and participates in

– Exs: family, child care, school, peer group

• Mesosystem: The interconnections among the environments in the child’s microsystem

– Ex: relations between family and peers

• Exosystem: Environments which the child does not directly experience but which affect his/her development indirectly

– Ex: parents’ workplace

• Macrosystem: Level involving culture, societal institutions, and public policy

– Ex: laws/policies concerning parental leave from work

• Chronosystem: Time

– Includes time over days, weeks, months, and years

Process-Person-Contexts-Time

(PPCT Model)

Proximal Processes

• Development occurs through processes of “progressively more complex reciprocal interaction between an active . . . [individual] and the persons, objects, and symbols in its immediate external environment” (Bronfenbrenner, 2006)

• Such interactions must occur on a fairly regular basis over extended periods of time to be effective in promoting development

– Exs: comforting an infant, playing with a young child, child-child activities, group or solitary play, reading, learning new skills, athletic activities, problem-solving

• For children, participation in such interactions over time leads to the knowledge/skills and motivation to engage in such activities with others and independently

• Proximal processes are bidirectional

• Proximal processes (within the microsystem) are the “engines of development”

• Proximal processes vary systematically due to

– Person (individual characteristics)

– Contexts (immediate and more remote environments—micro-, meso-, exo-, and macrosystems)

– Time (stability of proximal processes over time as well as societal changes during the life course and the historical period in which an individual lives)

• Interdependencies among the four components of the model

– “In ecological research, the principal main effects are likely to be interactions”