Previous research regarding the biosocial approach to aggression suggests that the interaction between biological and environmental variables contribute to aggression. However, this particular relationship has not yet been fully explored in children. Therefore, this study examined the moderating influence of psychophysiological activity, particularly resting heart rate (HR) and HR variability (HRV), on the relationship between child abuse potential (CAP) and child reactive and proactive aggression.

Thirty-six children, between the ages of 7 and 13, and their parents were recruited from the local schools and community in Southwestern Virginia. Parents completed self-report measures for child abuse potential (CAP) and the type of aggression displayed by their children (i.e., reactive or proactive). Children were assessed for resting HR and HRV for four minutes during a rest period.

CAP was related to increased proactive (i.e., instrumental) and reactive (i.e., hostile) aggression in children with low levels of resting HR. CAP was also related to increased proactive aggression in children with high resting HRV. Significant main effects were not found for CAP or psychophysiological functioning, indicating the importance of examining the interaction of these variables.

Taken together, the findings suggest the existence of an interaction of these two biological and social variables above and beyond their individual influences as risk factors.

The role of cardiovascular underarousal in relation to proactive and reactive aggression in abused children is discussed. Overall, this study supports the notion of a biosocial interaction for aggression in children, and thus has implications for future research and treatment.