The Current Period (1985–Present) 213Advances in Theory and Method
In this period, from 1960 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 contex-
tualism 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 in-
teraction 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 pe-
riod 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 achieve-
ments, began to emerge. A glimmer of recognition that theo-
ries 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 sec-
ular 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 ef-
fects of early preschool experience on children’s development
by Ramey & Haskins, 1981). There was a shift toward a lifes-
pan 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 col-
lected (e.g., Harlow & Harlow, 1962; Sackett, 1968; L. J.
Yarrow, 1961), it also became apparent in this period that sim-
ple 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 (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 to-
ward a mature interdisciplinary developmental science.Return to the Biology of DevelopmentOf 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 in-
vestigation 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 sophisti-
cated understanding of the potential role that genetics can
play not only in the onset of certain behaviors but in the un-
folding 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 mark-
ers 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 re-
searchers are documenting the clear and necessary role of
the environment in this process. Plomin’s (1994) reformula-
tion of genetic questions has led to a call for studies of
nonshared-environment effects and represents a good exam-
ple 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 de-
bate, 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 mean-
ingful 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 behav-
ior genetics. At the same time, advances in the measurement
and conceptualization of specificenvironmental influences