Videotaped 2-, 4-, and 6-month olds during interaction with a female adult stranger engaging in organized or disorganized peekaboo games. Found that from a diffuse sensitivity to the presence of a social partner, infants by 4 months develop a new sensitivity to the narrative envelope of protoconversation, in particular the timing and structure of…

Examined the number and nature of temperamental types in 488 children, age 3 years 6 months. Configural-frequency-analysis methods showed clear support for two temperament types: controlled-nonexpressive and noncontrolled-expressive. These types showed meaningful differences against external criteria related to a wide range of problem behaviors.…

Explored genetic and environmental underpinnings of temperamental differences in 3- to 16-month-old twins and their parents. Found that additive genetic and shared environmental effects best represented smiling, laughter, and duration of orienting. Shared environmental effects fully accounted for co-twin similarity for soothability. Additive…

Compared verbal and visuo-spatial working memory (WM) performance under initial, gain, and maintenance conditions for nine age groups from 6 to 57 years to determine if differences were attributable to specific or general processing functions. Found support for a general-capacity explanation of age-related differences, reflecting demands placed on…

Used a modified visual-fixation-based auditory-preference procedure to test preferences for infant-directed singing versus adult-directed singing in 15 two-day-old hearing infants of deaf parents. Subjects heard a Japanese and an English play song. Found that infants prefer infant-directed singing over adult-directed singing and that the…

Two studies examined efficacy of context reinstatement in enhancing 5- to 7-year olds' recall. Results showed that children exposed to a context reminder 24 hours before the six-month interview and children interviewed in the event context did not differ but reported significantly more information than children in standard interview. (Author/KB)

Examined association between residential density and parent/child speech in toddlers and parents participating in the University of Kansas Language Acquisition Project. Found that parents in crowded homes spoke with children in less complex, sophisticated ways than parents in uncrowded homes. The association was mediated by parental…

Three samples of 8- to 16-year olds were assessed three times at yearly intervals on eight water-level items. Within-child change over age was viewed as stochastic process of the child changing or remaining in one of three latent strategy states. Although there was improvement in task performance over age, the general finding was that strategy…

Examined mothers' representations of their relationship with toddler sons over a 13-month period. Found that the three factors characterizing mothers' representations for 15-month olds also fit data for 28-month olds. Found significant increases in anger but no changes in joy, pleasure, coherence, guilt, and separation distress. Changes in…

Administered five Piagetian tests to 180 adolescents for comparison to similar samples from 1967 and 1972. Found that today's adolescents exhibited higher levels of cognitive development than did previous cohorts. Gain varied across tasks, being very large for combinatory thought but mixed for conservation. This acceleration of cognitive…

Three experiments explored 3- and 4-year olds' use of external representations. Results indicated that 4-year olds outperformed 3-year olds on self-recognition task; children performed better with photographs than drawings; a delay had no effect. Results suggested that assessments of self and other understanding may reflect children's ability to…

Two experiments used the preferential looking task to assess early word comprehension in 12- to 24-month olds. Results indicated that when target stimuli were named, 12-month olds displayed an increase in target looking for typical--but not atypical--targets, whereas 18- and 24-month olds displayed increases for both. (Author/KB)

Examined cultural variation in management of attention by 14- to 20-month olds and caregivers from Guatemalan Mayan community and middle-class community of U.S. European-descent families. Found that Mayan caregivers and toddlers were more likely to attend simultaneously to spontaneously occurring competing events than were U.S. caregivers and…

Evaluated 9-, 14-, and 19-month olds' strategies as they grasped and used spoons presented with the handle alternately oriented to left or right. Found that younger children reached with their preferred hand, disregarding the item's orientation. Older children anticipated the problem, alternated the hand used, and achieved an efficient radial grip…

Used weekly-obtained longitudinal observational data of infant crying, fretting/fussing, and smiling and the time spent in physical contact with mother to examine behavioral variability over a 15-month period. Found evidence of an important intraindividual variability between newborn and 5 months, and 5 and 10 months, but not between 10 and 15…