Hungry for inclusion: Exposure to peer victimization and heightened social monitoring in adolescent girls.

Belonging to a social group is one of the most important factors contributing to well-being. The Belonging Regulation model proposes that humans possess a social monitoring system (SMS) that evaluates social inclusion and monitors belonging needs. Here, we used a prospective longitudinal design to examine links between peer victimization experienced across 7 years and social monitoring at the behavioral and neural level in adolescent girls (n = 38, Mage = 15.43 years, SD = .33). Participants completed a social evaluation task during a functional magnetic resonance imaging (fMRI) scan. More severe peer victimization was associated with increased activation to in-group versus out-group peers in the amygdala, ventral striatum, fusiform gyrus, and temporoparietal junction. Moreover, participants who displayed increased activation in these regions reported lower social self esteem and higher levels of internalizing and externalizing symptoms. These results suggest that exposure to peer victimization across the school years is associated with heightened social monitoring at the neural level during adolescence, which has potential adverse implications for girls' adjustment and well-being.