ROI analyses

For each study, we extracted the response profiles from the same anatomical regions-of-interest (ROIs) for left and right PGa and PGp. Anatomical ROIs were defined as the maximum probability maps for these cytoarchitectonic areas (Caspers et al. 2006, 2008) provided by the SPM Anatomy toolbox (Eickhoff et al. 2005, 2006). For each experimental condition and participant, we estimated percent signal change (PSC) as compared to the resting baseline using the MarsBaR toolbox (Brett et al. 2002). For statistical inference, we first performed one-sample t-tests on each experimental condition to test for significant activation or deactivation from the resting baseline. Second, to investigate relative activity differences between experimental conditions, we ran repeated-measures ANOVAs, correcting for non-sphericity using the Huynh–Feldt method. Significant interactions were resolved via step-down ANOVAs and post-hoc paired t-tests. p-values were corrected for multiple comparisons using the Bonferroni-Holm method.