Effects of acute stress on social conformity: Testing competing hypotheses

While prior research has focused on stress effects in individual decision-making, far less is known about its impact in social contexts, where judgments are shaped by others' opinions. Theoretical and empirical work offers competing predictions as to whether acute stress increases or decreases social conformity. Across two preregistered experiments (total N = 217), we tested these competing hypotheses using the Trier Social Stress Test - Online Version (TSST-OL; Study 1) and the Maastricht Acute Stress Test (MAST; Study 2) to induce stress. Participants were randomly assigned to either a stress or a control condition and completed a perceptual decision-making task measuring conformity. Results provided evidence for reduced conformity under stress, particularly in Study 1 and in pooled analyses. This pattern is consistent with the stress-breeds-social-independence hypothesis. Exploratory mediation analyses further suggest that this effect is linked to lower perceived competence of others. In contrast, other psychological (e.g., state self-esteem, sense of agency, mood) and physiological variables (i.e., salivary cortisol) were affected by stress but were unrelated to conformity. Furthermore, we examined potential moderators of the stress-induced decrease in conformity, including gender and the social embeddedness of the situation, but did not observe evidence for moderation by these variables. Taken together, the overall pattern of results, including the pooled analyses, provides evidence that acute stress reduces social conformity.