Strong hearts, open minds: Cardiovascular challenge predicts non-defensive responses to ingroup-perpetrated violence

Reminders of ingroup-perpetrated violence represent a psychological stressor that some people respond to defensively (e.g., justifying the violence), while others react non-defensively (e.g., accepting collective responsibility). To explain these divergent responses, we applied the biopsychosocial model of challenge and threat to the context of intergroup conflict. Participants (N = 130) read about either an ingroup (American) or outgroup (Australian) soldier torturing an Iranian captive. We recorded cardiovascular responses while participants video-recorded introductions to an Iranian confederate who they believed they would meet. In the ingroup (but not the outgroup) condition, cardiovascular responses of challenge (relative to threat) were associated with less psychological defensiveness of ingroup-perpetrated violence and greater support for diplomacy towards its victims. Self-reported challenge/threat appraisals demonstrated no such relationships. These findings suggest that motivational states of challenge and threat can differentiate defensive and non-defensive responses, and that these motivational states may be better captured with physiological rather than self-report measures.