The Influence of Group Favoritism on Moral Judgment -- Evidence From Event-Related Potential.

This article investigates how group favoritism influences moral judgments by examining neural responses using event-related potentials (ERPs). Two experiments compared moral evaluations of behaviors performed by in-group members versus either homogeneous out-groups (groups of similar social status and competition) or high-quality out-groups (groups with superior status). Results showed that participants rated in-group members' behaviors as more moral than those of homogeneous out-groups, accompanied by greater P2 ERP amplitudes and distinct N400-like responses, indicating heightened attention and emotional conflict toward out-group members of similar status. In contrast, no significant differences in moral judgments or ERP responses were found between in-groups and high-quality out-groups, suggesting that perceived group characteristics moderate favoritism effects. The study highlights that in-group favoritism affects moral evaluation primarily when out-groups are perceived as direct competitors, offering insights into the neural mechanisms underlying social biases in moral decision-making.