Three studies showed that 5- to 9-year-olds and adults do not usually base their spellings of plural real-word and pseudo-word endings on the morphological rule that all regular plurals are spelled with -s. Participants appeared to use their knowledge of complex but untaught spelling patterns, which is based on the frequency with which certain…

Tested prefrontal and hippocampal functions in school-aged individuals with Down syndrome (DS) compared functions with those of typically developing children individually matched on mental age. Found that hippocampal and prefrontal composite scores contributed unique variance to the prediction of mental age and adaptive behavior. Noted a…

Three experiments investigated 2- to 6-month-olds' perception of the continuity of an object trajectory that was briefly occluded. Results across experiments provided little evidence of veridical responses to trajectory occlusion in the youngest infants, but by 6 months, perception completion was more robust. Results suggest that perceptual…

Data were analyzed from an epidemiological sample of 5-year- old twins and their parents. Findings indicated that the less time fathers lived with their children, the more conduct problems their children had, but only if the fathers engaged in low levels of antisocial behavior. When fathers engaged in high levels of antisocial behavior, the more…

Investigated hypothesized reciprocal influences between stressful life events and adolescent maladjustment using data from 6-year, prospective longitudinal study. Found that from seventh to twelfth grades, stressful life events, internalizing symptoms, and externalizing behaviors were reciprocally interrelated over time. Found that stressful life…

Two experiments tested claim that transparency of Korean fraction names promotes fraction concepts. Findings indicated that U.S. and Korean first- and second-graders erred similarly on a fraction-identification task, by treating fractions as whole numbers. Korean children performed at chance when whole-number representation was included but…

Three studies examined development of the perception of temporally unidirectional transformation, such as dropping blocks, with 3.5- to 6.5-year-olds who compared forward and backward videotapes of events or made individual judgments of what would happen if action were attempted. Findings indicated that even 3.5- to 4.5-year-olds recognized the…

Three studies explored whether children's tendency to extend object names on the basis of sameness of shape (shape bias) is specific to naming. Findings indicated that 2- and 3-year-olds showed shape bias both when asked to extend a novel name and when asked to select an object of the same kind as a target object; 3-year-olds also showed shape…

Two experiments with monolingual German-speaking 2.5- to 4.5-year-olds showed a consistent developmental gap between children's memory/inference of what someone wanted and what someone wrongly said or thought. Correct answers emerged with mastery of the false-belief task. It was concluded that the observed gap constrains de Villiers's linguistic…

Examined association of family-related factors with children's depression and conduct problems among low-income Mexican American (English- and Spanish-speaking) and European American mothers and children. Found ethnic differences in children's depression, maternal inconsistent discipline, and hostile control. Also found language differences within…

Examined peer group contextual effects of aggressive behavior among middle school students. Found substantial within-group similarity on self-reported bullying and fighting, suggesting that students affiliate with individuals who bully and fight at the same frequency as they. Peer group bullying and fighting were associated with individual-level…

Two studies investigated whether 10- and 12-month-olds can use televised emotional reactions to guide their behavior. Findings indicated that 12-month-olds avoided the target object and showed increases in negative affect after observing an actress orient toward a novel object with negative affect, but their responses to positive versus neutral…

Assessed preschoolers' patterns of emotional expressiveness, emotion regulation, and emotion knowledge. Used latent variable modeling to identify their contributions to social competence, evidenced by sociometric liability and teacher ratings. Found that emotional competence assessed at 3 to 4 years of age contributed to both concurrent and…

Proposed and tested a diathesis-stress model in which the joint forces of individual vulnerability (anxious solitude) and interpersonal adversity (peer exclusion) predict children's depressive symptoms over time. Found that anxious solitude and peer exclusion co-occur in children soon after kindergarten entry and that anxious solitary children who…

Examined data from the National Longitudinal Study of Adolescent Health to determine impact of school-level substance use on adolescent-peer similarity for smoking and drinking. Found that adolescent-peer similarity was significantly moderated by school-level substance use for both tobacco and alcohol use. Inferred that schools with relatively few…