The Role of Autonomic System Coordination in Relations Between Peer Factors and Aggressive Behavior in Early Childhood.

This study tested biological sensitivity to context theory in the peer context. Respiratory sinus arrythmia (RSA-R) and skin conductance level (SCL-R) reactivity to a peer stressor were collected for participants (N = 86; M age = 45.99 months old; 70.2% White) in the summer (Time 1). Children's peer risk (i.e., physical and relational victimization) and protective (i.e., received prosocial behavior) factors were examined in the fall (T2) and relational and physical aggression were measured at T2 and in the spring (T3). Interactions were tested in regression analyses. Interactions emerged between relational victimization, RSA-R, and SCL-R in the prediction of T3 relational aggression and between received prosocial behavior, RSA-R, and SCL-R in the prediction of T3 relational and physical aggression, respectively. There was a positive relation between T2 relational victimization and T3 relational aggression for children with a coactivation pattern (i.e., increased RSA and SCL activity to a bullying stressor) but no relation for any other physiological pattern. Conversely, there was a negative relation between T2 received prosocial behavior and both forms of aggression at T3 for children with a reciprocal pattern (i.e., increased RSA and decreased SCL or decreased RSA and increased SCL activity) but no protective benefit of received prosocial behavior on subsequent aggression for children with a coactivation pattern. For children with a coinhibition pattern (i.e., decreased RSA and SCL activity), received prosocial behavior was negatively related to subsequent physical but not relational aggression. In sum, a coactivation pattern in response to stress may represent a vulnerability factor.