Suggests that testing developmental ordering hypotheses is difficult because rare use of ratio scales prevents direct comparison of measures. Demonstrates that the observed data pattern is constrained by the underlying relationship--although observed data pattern may not reflect the exact relationship, it limits possible relationships. Shows the…

Three experiments examined children's understanding of functional relations in economics. Found that preschoolers understood effects of demand and second graders also understood effects of supply, but even fourth graders often failed to understand motivation and morality effects. Fourth but not second graders explained how motivation and morality…

Four experiments and an analysis of pooled data from English and Japanese children show a linear increase in understanding false beliefs with number of older siblings; no such effect for children younger than 38 months; no helpful effect of younger siblings at any age; no effect of siblings' gender; and no helpful effect of siblings on a source…

Examined scientific reasoning and self-serving reasoning biases in 5th, 8th, and 11th graders. Found that scientific reasoning improved with age. Ratings of evidence quality and written justifications yielded mixed results regarding developmental trends in reasoning biases. Theoretical beliefs regarding religion and ego-protective motivations…

Videotaped preschoolers playing while experimenter covertly placed and later removed a large sticker on their head. Procedure was repeated one week later. Found that most four- and five-year-olds who observed video taken three minutes earlier reached for the sticker, but few who saw video taken a week earlier did so. Fewer than half of the…

Developed measures of relational aggression for young children. Found that relational aggression appears at young ages and can be distinguished from overt aggression. Preschool girls are more relationally and less overtly aggressive than boys. Relational aggression is related to social-psychological maladjustment. (Author/KB)

Two studies examined children's and adolescents' attitudes toward aggression. Found that boys viewed physical aggression as more hurtful than social aggression and girls rated social aggression as more hurtful. Girls rated an aggressor as more angry than did boys. Middle and high school participants viewed social aggression as indicating more…

Replicated and extended American research on overt and relational aggression with Italian children. Found that peer and teacher nominations for aggression and prosocial behavior were highly stable, although with very poor concordance between them. Peer nominations for overt and relational aggression were linked to peer rejection. Boys' scores were…

Studied the adjustment status associated with engagement in gender normative versus gender nonnormative aggression for boys and girls. Teacher and self-reports were used to assess internalizing and externalizing difficulties. Found that 9- to 12-year olds who engaged in gender nonnormative aggression were more maladjusted than children who engaged…

Forty 3.5- to 4.5-year-olds discussed past events with their mothers and completed tasks indexing their ability to reason about conflicting mental representations and understanding of knowledge. Found that theory-of-mind scores were related to memory conversation participation, independent of age and linguistic skill, and to the frequency of…

Examined whether 30-month olds appreciate that their communicative signals are being understood by another. Separated listener comprehension from obtaining a material goal in communication. Children clarified their signal more when the experimenter misunderstood compared with when she understood. Regardless of achieving overt goal, children…

Conducted a three-year longitudinal analysis of morphological spelling strategies in second through fourth graders. Found that, when children first adopt morphologically determined spelling patterns, they disregard the morphological basis. Generalization progresses from grammatically inappropriate words to the right grammatical category to the…

Examined electrical brain activity during negative and positive emotion expression in infants of depressed and nondepressed mothers. Found that, compared with infants of nondepressed mothers, infants of depressed mothers exhibited increased EEG activation in the frontal but not parietal region when expressing negative emotions. There were no…

Examined relations among maternal depressive symptoms, family discord, and adolescent psychological adjustment. Found that maternal depressive symptoms were related to subsequent adolescent depressive symptoms, conduct problems, and academic difficulties for girls but not boys. Girls' greater vulnerability to family discord accounted for the…

Used path analysis to examine effects of spatial skill, math anxiety, and math self-confidence as mediators of gender differences in Mathematics Scholastic Aptitude Test (SAT-M) in upper third of college-bound adolescents. Found that mental rotation and math self-confidence indirectly mediated the gender-SAT-M relationship. Most of the mediational…