Heart Rate and Antisocial Behavior: Mediation and Moderation by Affiliation Bullies. The TRAILS Study

Purpose: Low heart rate has been linked to antisocial behavior. However, the effect of low heart rate may be mediated by affiliation with bullies. We hypothesized that individuals with low heart rate are more likely to affiliate with bullies and in turn are influenced by these peers. Method: Data come from two waves of a subsample of the TRAILS study (N=809; 44.0% boys; mean age 11.0 at T1 and 13.5 at T2). Antisocial behavior was measured via the Antisocial Behavior Questionnaire at both waves. Heart rate was assessed during rest at T1. Affiliation with bullies was assessed via peer-nominations at T1. Possible gender differences were taken into account and all analyses were adjusted for family context (i.e., family break-up and SES). Results: Regression analyses showed that lower heart rate was only associated with antisocial behavior in (pre)adolescents who affiliated with bullies. Moreover, the effect of lower heart rate on boys’ antisocial behavior went partly via affiliation with bullies. Conclusions: Our findings show that (pre)adolescents, and in particular boys, seem to be in environments that match their biological disposition and in turn are shaped by this environment.