Neural responses to reward in childhood: relations to early behavioral inhibition and social anxiety.

Behavioral inhibition (BI) is an early temperamental profile characterized by negative reactivity to novelty, withdrawal from social situations, and increased risk for social anxiety. Previous research associated BI assessed in early childhood to striatal hypersensitivity in mid-to-late adolescence. The present study examined this association among 10 year-olds, characterized with BI at ages 24 and 36 months on measures of temperamental reactivity. Participants (n = 40) were studied at age 10 using a reward processing task during functional magnetic resonance imaging (fMRI). Child- and maternal-report of social anxiety symptoms was collected at ages 10 and 13. Findings indicate greater caudate activation and stronger striatal connectivity in high, compared to low, behaviorally inhibited children. Caudate activation related to social anxiety symptoms at both ages. These findings suggest that enhanced striatal responsivity reliably manifests among high behaviorally inhibited children as early as age 10. This may reflect hyper-sensitivity to reward or excessive motivation to avoid errors.