Aggression Running Through Your Veins? The Relationship Between Heart Rate, Heart Rate Variability, and Aggression in Detained Juveniles: A Pilot Study

Aims: Aggression is one of the most important dynamic risk factors for recidivism in juveniles. The physiological underpinnings of aggression, such as the functioning of the Autonomic Nervous System (ANS), need further investigation to eventually improve diagnostics and treatment practices. Therefore, the present pilot study examined whether relations exist between ANS basal functioning (i.e., resting Heart Rate [HR] and Heart Rate Variability [HRV]) and proactive and reactive aggression; and between ANS responsivity (i.e., HR(V) in response to stressful conditions) and pro- and reactive aggression in detained juveniles. Methods: Participants were 27 detained boys (M_age = 17.37, SD = 1.31) from an all-boy Juvenile Detention Center in the Netherlands. Trait-level proactive and reactive aggression, cardiac measures, and potential lifestyle covariates were assessed. Pearson and Spearman correlations and multiple hierarchical regression analyses were conducted. Results: Results showed no significant associations between ANS basal functioning, ANS responsivity, and proactive and reactive aggression. Conclusions: This study adds to the literature by increasing knowledge on the link between both resting HR(V) as well as HR(V) responsivity and both forms of aggression and provides recommendations to further advance research in this field.