Forms and functions of social comparison verbalizations were studied among preschoolers in a naturalistic setting. Each social comparison statement was coded into content (ability, possession, status, attitude, activity) and function (diffentiation/similarity, cognitive clarity, evaluative, competitive) categories. Results indicated preschoolers…

Eighty children between the ages of 6 and 13 were asked to indicate and compare the needs and earnings of doctors, bus drivers, waiters, and shopkeepers. Youngest children did not perceive that unmet needs existed. Older children recognized the needs but sharply disagreed about inequalities. (Author/DB)

Sex differences and their relationship to individual differences were examined for Maccoby and Jacklin's sex differences summaries, for a diverse set of measures of specific cognitive abilities (including verbal ability), and for objective personality assessments of 216 school-age children. Average differences between groups appeared to be trivial…

Examines sex differences in vocalizations and play behaviors displayed toward an infant by preschoolers, preadolescents, and adults. Preschoolers showed less interaction than older subjects. Males talked and played less with the baby than did females at all ages; however, among adult subjects, no sex-role effects were found. (Author/RH)

Drug-exposed mother-infant rhesus monkey pairs were similar to nontreated controls in the amount and types of activity displayed at the infant's tenth and ninetieth day of age. At about 3 months of age drug-exposed pairs increased in interaction, signaling mother-infant independence. This finding suggests that mother-infant attachment may be…

Provides an introduction to a special section on developmental behavioral genetics (the study of genetic and environmental influences on individual differences in behavioral development), discussing the potentialities of the interdiscipline and presenting an overview of the following articles. (Author/RH)

Reviews findings of two large adoption studies. Both examined the levels of intellectual and personality development, as well as the degree of resemblance, among family members. Focus is directed toward intelligence quotient and school achievement tests, with briefer attention given to personality interests and attitudes. (Author/RH)

Intelligence test scores were obtained from parents and children in 300 adoptive families and compared with similar data available from the children's biological mothers. Results support the hypothesis that genetic variability is an important influence in the development of individual differences in intelligence. (Author/RH)

Provides an overview of a longitudinal, prospective, multivariate adoption study of behavioral development and discusses the results of analyses of cognitive measures and environmental assessments as examples of the types of information that can emerge from a design of this sort. (Author/RH)

Measures of general cognitive ability in one- and two-year-old adopted and nonadopted infants and their parents were subjected to path analysis to estimate the contribution of genetic and environmental factors to short-term stability of mental ability. (Author/RH)

Results show individual differences in intelligence progressively stabilizing by school age, with each child following a distinct pattern of mental development. Monozygotic twins became increasingly concordant over an Hes and were closely matched on developmental trends. (Author/RH)

Describes a mixed longitudinal analysis of 1,356 twins, (three to 15-years-old) their siblings, and cousins, who underwent a battery of physical and behavioral tests. The covariance structure analysis method in biometrical genetics was employed to specify determinants of the structure of cognitive abilities, to indicate how these change during…

Provides an overview of recent behavior-genetic studies of personality that document (1) the demonstration of genetic bases for stability of certain personality dimensions, (2) evidence suggesting the most influential environmental sources of variation are those not jointly experienced by family members, and (3) continuing controversy regarding…

Factor scores from Bayley's Infant Behavior Record (obtained from 300 to 400 infants at six, 12, 18, and 24 months) were selected to represent three aspects of infant behavior: task orientation, test affect-extraversion, and activity. Findings indicate reordering of individual differences is age-related and that the reordering sequence is somewhat…

To examine developmental patterns of and genetic influences on common fears, a 51-item survey was administered to more than 2,600 adolescents and adults, including more than 400 pairs of like-sex twins. Findings suggest significant genetic modulation of developmental patterns in the acquisition and maintenance of some adaptive fears. (Author/RH)