A systematic review of ego depletion phenomenon in group-based hierarchical relations.

Introduction: This systematic review examines the relationship between intergroup relations and ego depletion, aiming to understand how self-control resources are affected in social hierarchies. Methods: A total of 35 peer-reviewed articles and four unpublished doctoral dissertations were reviewed. Findings were categorized based on the social position of the target person's group in intergroup interactions. Results: Intergroup contacts depleted the self-control resources of dominant group members when they were required to suppress biases. For subordinate group members, engaging in intergroup interactions, witnessing bias, or facing bias threats also depleted self-control resources. Depleted dominant members exhibited increased prejudice and stereotyping, whereas depleted subordinate members showed lower perception of prejudiced behaviors and higher liking for dominant group members. Discussion: The findings are interpreted within the framework of social dominance theory, highlighting how ego depletion influences intergroup relations and reinforcing the role of group-based hierarchies in shaping social behavior.