Breaking down internal barriers: The role of physical protection in attenuating ingroup derogation

Intergroup bias manifests not only as ingroup favoritism but also as ingroup derogation-a counterintuitive preference for outgroup over ingroup members, predominantly observed in East Asian cultures. Building on previous research suggesting ingroup derogation functions as an adaptive response to situations where intragroup aggression exceeds intergroup threats, this study investigated whether physical protection against interpersonal aggression attenuates ingroup derogation. Three experiments employed the minimal group paradigm with Chinese participants. In Experiment 1 (N = 120), participants wearing safety helmets showed significantly reduced ingroup derogation compared to controls. Experiment 2 (N = 320) revealed that stab-proof vests not only eliminated ingroup derogation but reversed it to ingroup favoritism-an effect consistent across personality type assignments. Critically, protective equipment specifically reduced perceived vulnerability to interpersonal aggression rather than general safety concerns. Experiment 3 (N = 176) extended these findings behaviorally: control participants demonstrated automatic tendencies to avoid ingroup and approach outgroup members, while participants wearing protective vests displayed the opposite pattern. Although chronic concerns about interpersonal aggression predicted stronger ingroup derogation, they did not moderate the protective equipment effects. These findings provide evidence that ingroup derogation functions as a context-sensitive psychological mechanism calibrated to manage aggression threats, adhering to both smoke detector and functional flexibility principles. The results highlight how environmental safeguards can recalibrate intergroup biases, illuminating the dynamic nature of social preferences across ecological contexts.