This study investigated the normative use and developmental course of physical aggression (PA), defined as use of physical force such as hitting, biting, and kicking, from 8 to 26 months and predictors thereof. We used data from the Behavior Outlook Norwegian Developmental Study, comprising 1,159 children (559 girls and 600 boys). Both mothers and…

Two studies addressed key theoretical debates in theory of mind (ToM) development by comparing (a) deaf native signers (n = 18), (b) deaf late signers (n = 59), and (c) age-matched hearing persons (n = 74) in childhood (Study 1: n = 81) and adulthood (Study 2: n = 70) on tests of first- and second-order false belief and conversational sarcasm.…

Children's theory of mind (ToM) is typically measured with laboratory assessments of performance. Although these measures have generated a wealth of informative data concerning developmental progressions in ToM, they may be less useful as the sole source of information about individual differences in ToM and their relation to other facets of…

According to Klahr's (2000, 2005; Klahr & Dunbar, 1988) Scientific Discovery as Dual Search model, inquiry processes require three cognitive components: hypothesis generation, experimentation, and evidence evaluation. The aim of the present study was to investigate (a) when the ability to evaluate perfect covariation, imperfect…

Every sphere of life has been revolutionised by science. Thus, science understanding is an increasingly precious resource throughout the world. Despite the widely recognised need for better science education, the percentage of school students studying science is particularly low, and the numbers of students pursuing science continue to decline…

We examined behavior problems in 80 adolescents (39 male; mean age = 15.74 years) adopted in early childhood by Canadians from globally depriving Romanian institutions. Overall, rates of clinically significant behavior problems were comparable to rates found in younger postinstitutionalized adopted children. The association between duration of…

Metacognition refers to students' knowledge and regulation of cognition, as well as their accuracy in predicting their academic performance. This study addressed two major questions: 1) how do metacognitive knowledge, regulation and accuracy differ across domains?, and 2) how do students' individual differences relate to their reported…

This study examined the relations among family conflict, community violence, and young children's socioemotional functioning and explored how children's social cognition and mothers' psychological functioning may mediate the outcomes associated with this exposure. Mothers of 431 Head Start preschoolers completed questionnaires about their family…

Findings are presented of a study of families created through surrogacy arrangements. Forty-two surrogacy families were compared with 51 egg-donation families and 80 natural-conception families on standardized interview and questionnaire measures of the psychological well-being of the parents, the quality of parent-child relationships, and infant…

This longitudinal study of adolescent girls and boys examined the contributions of social (peer appearance context), psychological (internalized appearance ideals and appearance social comparison), and biological (body mass) factors to the development of body dissatisfaction. Students (165 girls and 139 boys) completed questionnaires when they…

Phase 1 of this study found that, among fourth and fifth graders, submissive children who were rejected by peers reported less positive beliefs about peers than did children of average status. In phase 2, no relationship between children's sociometric status and their beliefs about unfamiliar peers was found. (BC)