Developmental and Individual Differences in Reward Processing across Childhood and Adolescence

Title of thesis: DEVELOPMENTAL AND INDIVIDUAL DIFFERENCES IN REWARD PROCESSING ACROSS CHILDHOOD AND ADOLESCENCE Michael L. Kirwan, M.A., 2010 Thesis directed by: Distinguished University Professor Nathan A. Fox, Department of Human Development Adolescence is a developmental period characterized by maturation across multiple domains. This maturation is not without difficulties, however, as adolescents also display increased negative mood, conflict with parents, and risk-taking behaviors. Increased risk-taking is thought to be the byproduct of changes in reward circuits in the brain, and while a solid foundation of research has provided evidence for changes in reward processing during adolescence compared to adulthood, little is known about the changes that occur from childhood into adolescence. The current study addresses this gap in the literature with an investigation of changes in behavioral performance on a reward-processing task using a cross-sectional sample of children and adolescents. Three primary findings emerged from this study. First, adolescents displayed faster reaction times than 8-year-olds. Second, subjects responded faster and more accurately on trials with greater potential rewards. Finally, individual differences were related to reward sensitivity, reaction times, and response accuracies. DEVELOPMENTAL AND INDIVIDUAL DIFFERENCES IN REWARD PROCESSING ACROSS CHILDHOOD AND ADOLESCENCE