Related Experiment Video
Updated: Aug 30, 2026

Continuous Theta Burst Stimulation of the Posterior Medial Frontal Cortex to Experimentally Reduce Ideological Threat Responses
Published on: September 28, 2018
Party over policy: The dominating impact of group influence on political beliefs
1Department of Psychology, Yale University, New Haven, CT 06520-8205, USA. geoffrey.cohen@yale.edu
Abstract:
Four studies demonstrated both the power of group influence in persuasion and people's blindness to it. Even under conditions of effortful processing, attitudes toward a social policy depended almost exclusively upon the stated position of one's political party. This effect overwhelmed the impact of both the policy's objective content and participants' ideological beliefs (Studies 1-3), and it was driven by a shift in the assumed factual qualities of the policy and in its perceived moral connotations (Study 4). Nevertheless, participants denied having been influenced by their political group, although they believed that other individuals, especially their ideological adversaries, would be so influenced. The underappreciated role of social identity in persuasion is discussed.
Related Concept Videos
Group Polarization
Impact of Groups on Individuals
Impact of Groups on Groups
Groupthink
Social Psychology and Individual Behavior
Impact of Individuals on a Group
