Three experiments examined whether 8.5-month-olds considered an object's width and compressibility when determining whether it could be inserted into a container. Results suggested that infants realized that large balls could fit into large but not small containers, whereas small balls could fit into both containers. Infants understood that large…

Examined relations among measures of child language derived from observations of 20-month-olds' speech with mothers, experimenter assessments, and maternal reports. Found that structural equation modeling supported strong relations among the three sources, the loading of multiple measures on a single latent construct of vocabulary competence, and…

Three studies examined whether preschoolers' difficulties with deception and false belief arise from lack of inhibitory control rather than conceptual deficit. Found that 3-year olds deceived frequently under conditions requiring relatively low inhibitory control, but not high inhibitory control. Findings were not due to social intimidation, and…

Three studies examined children's understanding of looking behavior in revealing another's desired goal. Found that 6-year olds and adults, but not 4-year olds, consistently regarded prolonged looking as a more important cue than glancing or inadvertent touching of the protagonist's goal. Results suggest that development is characterized by…

Examined 3- to 5-year olds' justifications for conformity to physical laws and social rules. Found that children's justifications for social rule conformity involved consequences and permission/obligation, and for physical laws involved physical limitations or impossibility. Older preschoolers, but not 3-year olds, appreciated that social…

Two studies of adolescents in England and Russia examined the effects of prolonged instruction on students' development of abstract deductive reasoning and understanding of logical necessity in algebraic and verbal reasoning. Results indicated that prolonged instruction emphasizing the metalevel of algebraic deduction contributed to enhanced…

Two studies examined age differences in conditional reasoning. Results indicated that 8-year-olds performed better when antecedents were weakly associated with consequents than on strongly associated antecedent/consequents, with no difference among 11-year-olds. Eight-year-olds did better on ad hoc premises than on causal premises, with no…

Investigated hypothesis that individuals evaluate self-worth differently across relational contexts while holding perceptions of global self-worth. Found that adolescents' self-worth perceptions varied across contexts. Support in a given context was more highly correlated with relational self-worth in the corresponding context than in other…

Examined the relations of teachers' and parents' reports of children's shyness at ages 6-8, 8-10, and 10-12 years to dispositional regulation, emotionality, and coping. The overall pattern of findings was partially consistent with the conclusion that parent-rated shyness reflected primarily social wariness with unfamiliar people, whereas…

Compared psychological adjustment of adopted adolescents and their siblings born to adoptive parents. Found poorer adoptee adjustment in areas of delinquency, licit drug use, and school adjustment. Nonclinically referred adopted boys were better adjusted than norm subjects on withdrawal; nonreferred adopted girls were better adjusted on social…

Tested a model linking maternal/family characteristics to child cognitive and psychosocial competence in African-American 6- to 9-year olds in rural single-mother-headed households. Found that maternal education, religiosity, and financial resources were linked with parenting style, mother-child relationship, and maternal school involvement.…

A series of meta-analyses identified changes in parent-child conflict during adolescence and moderating factors. Results of age meta-analyses indicated that conflict rate and total conflict declined from early to mid adolescence and from mid to late adolescence; conflict affect increased from early to mid-adolescence. Puberty meta-analyses…

Examined personal storytelling of European-American preschoolers from working- or middle-class families as a medium through which they construct autonomous selves. Found that children in both communities had extensive rights to speak of past experiences and limited rights to author experiences. Middle-class communities viewed expressing one's view…

Offers a typology of emergent literacy skills, reviews research relating emergent literacy to reading, and reviews evidence linking emergent literacy environments and development of emergent literacy skills. Proposes that emergent literacy consists of inside-out skills and outside-in skills that are influential at different times during reading…

Studied relationship between adolescents' sleep/wake habits and daytime functioning. Found that self-reported total sleep times decreased from age 13 to 19 years. Struggling or failing students obtained less sleep, went to bed later, and had greater weekend delays of sleep than those with better grades. Students with inadequate sleep reported…