PurposeRecent research has identified different psychobiological mechanisms underlying Intimate Partner Violence (IPV). However, vagally mediated heart rate variability (vmHRV), a measure of parasympathetic activity, has been scarcely studied in IPV perpetrators. Low vmHRV activity has been found to be associated with maladaptive emotion regulation strategies and negative affect, whereas high vmHRV functioning has been related to higher social engagement, positive affect, prosocial behavior and compassion. MethodsThe present study examined vmHRV, mood state and prosocial behavior in a Compassion-eliciting Task, through a virtual reality paradigm, in 39 IPV offenders, compared to 42 general offenders (GO) and 43 non-forensic control participants. Additionally, it explored whether phasic vmHRV could explain the mood change in response to the Compassion Task. ResultsIPV offenders showed lower vmHRV activity during the task when compared to non-forensic participants. No significant differences were obtained between IPV and GO. Furthermore, higher vmHRV partially explained lower negative affect after the Compassion Task for the entire sample. ConclusionsFindings suggest that IPV offenders experience difficulties connecting with others' suffering. It also highlights that the use of biomarkers, such as vmHRV, in the study of criminogenic factors may provide a broader understanding that could promote more effective interventions.