(a) Male and female participants showed no between-group differences in either risk preference (independent sample t-test, t(60) = 0.87, P = 0.39, two-tailed), conformity (independent sample t-test, t(60) = 1.20, P = 0.24, two-tailed), or conformity bias (independent sample t-test, t(60) = –0.56, P = 0.58, two-tailed). We also included gender as a covariate in the behavioral analyses to assess potential gender differences in the preference-dependent conformity predicted by the OCU model (per main text Fig. 2b). Both males and females show preference-dependent conformity biases, and gender was not a predictor of this pattern (multiple linear regression, t = –1.15, P = 0.25). (b, c) Nonetheless, to evaluate and control for potential gender effects, we also performed additional analyses adding gender as an extra nuisance regressor to the neural general linear model (GLM) analyses presented in the main text. All results with the gender covariate added to the GLM are comparable with those reported in the main text Fig. 3a and 3c. All displayed maps are displayed at P <.001 uncorrected, k > 10 contiguous voxels; the vmPFC and dACC clusters are significant at P < 0.02 FWE, SVC; the insula cluster is significant at P < 0.02 FWE; error bars show s.e.m.