Parent-Child Neural Dynamics during a Stressful Task: Probing Associations with Temperament and Anxiety

Dynamic social interactions between parents and children can contribute to anxiety risk, amplifying shared genetic risk. Research has focused on observed behaviors to explain intergenerational transmission. Neural synchrony may contribute as a biological conduit for behavioral transmission of risk. We examined 109 parent-child dyads (M _age=5.81 years; SD=1.2, 55 girls; 66 mothers) during a mildly stressful interaction (DB-DOS: BioSync), using fNIRS. Synchrony was lower during the Recovery block than during Baseline, with no significant differences between the Stressful and Baseline conditions. Synchrony significantly decreased in dyads with children higher in Effortful Control during Recovery, consistent with flexible adjustment after stress. Dyads with children higher in Fear showed reduced VLPFC synchrony during Recovery compared to Baseline. Higher parental state anxiety was associated with lower VLPFC synchrony. Neural synchrony may be sensitive to context, and individual traits linked to anxiety risk and resilience, providing potential targets for prediction and intervention.