The longitudinal association between competitive video game play and aggression among young adults and adolescents was examined. Young adults (N = 1,132; M[subscript age] = 19 years) were surveyed annually over 4 years about their video game play and aggression, and data from a 4-year longitudinal study of adolescents (N = 1,492; M[subscript…

In one of the first open diffusion experiments with young children, a tool-use task that afforded multiple methods to extract an enclosed reward and a child model habitually using one of these methods were introduced into different playgroups. Eighty-eight children, ranging in age from 2 years 8 months to 4 years 5 months, participated. Measures…

The twofold purposes of the investigation were (a) to describe with direct observation data the physical activity behaviors and the accompanying social and environmental events of those behaviors for children in preschools and (b) to determine which contextual conditions were predictors of moderate to vigorous physical activity (MVPA) and…

Examined concurrent and longitudinal links between observational measures of 8- to 9-year olds' playground behaviors/peer contacts (alone, conversation, group size, and network) and three sociometric measures of peer relationships (social preference, bully, and victim). Found significant concurrent and predictive relationships, with relationships…