Behaviorally inhibited preschoolers experience stronger connectivity among social-related neural regions while interacting with a stranger.

Social behavioral inhibition (BI), or wariness in response to unfamiliar social stimuli, is a temperament trait that, when present in preschool-age children, predicts neural alterations and anxiety disorders by adolescence. The current study assessed neural functioning associated with BI during the preschool years. Our sample was enriched for BI based on mother report and included 59 preschool-age children (54 % female, M = 3.7 years). Children interacted with an unfamiliar experimenter via the Stranger Approach paradigm from the preschool version of Lab-TAB, and neural data were collected simultaneously to measure neural response to an unfamiliar social encounter. Children who exhibited more social BI-related behaviors experienced stronger functional connectivity between multiple social-related neural regions, including the temporoparietal junction, superior temporal gyrus, and medial and lateral prefrontal cortex while interacting with a stranger. Additionally, children who experienced stronger connectivity between the right and left temporoparietal junction had greater mother-reported anxiety symptoms one year later. Our results suggest that observable social BI during early childhood is associated with distinct neural patterns, which may elucidate biomarkers that underlie risk for later anxiety.