Examines the interplay between genes and environment and argues that the development of much individual variation can be explained in terms of relatively simple forms of underlying regulation. Looks at "sensitive periods," during which variation is produced by experience received at a particular age. Includes a discussion of the…

Reviews evidence for a cognitive theory of aging which attempts to integrate individual perceptions, social perceptions, and integrative processes with biological, social, and ecological influences and behavior patterns. (BD)

Explores the case for viewing altruism as an inherent part of human nature. Postulates an altruistic disposition or motive to act which is under the control of perceptual and cognitive processes. Presents psychological evidence complementing this view. Discusses social implications of a biological basis for human altruism. (RH)

Investigated the effects of biomedical and social-environmental conditions on cognitive and language development in children toddlers. Hypothesized a strong effect of biomedical factors in first two years and a strong environmental influence at three years. Used analysis approach to estimate variables assumed to underlie measurement data. Results…

Suggests an explanation for the link between environment, malnutrition, and rate of mental development in children. It is argued that biological factors and difficult socioeconomic conditions interact to slow mental development by undermining the establishment and maintenance of a "syntonic,""synchronic," and "reciprocal" relationship between the…

Discusses research on human development from an interactional perspective; methodological problems connected with interindividual differences in biological maturation (using empirical studies from a longitudinal program); and major implications for further development research in an interactional perspective. (Author/BE)

Reviews evolutionary, psychoanalytic, social learning, and cognitive developmental approaches to the development of altruism and proposes a framework that integrates the approaches. The four approaches are compared in terms of three general issues: the origin of altruism, the conception of altruism as a state or a trait, and individual differences…