Topographical distribution of relative SWA (0.8–4.6 Hz) and its correlation with prosocial preferences. A, Topographical distribution of relative SWA (average over all participants). SWA values at every electrode were normalized in relation to the average SWA over all electrodes of a participant. The dark blue to dark red colors indicate minimal (45%) to maximal (173%) SWA. B, Statistical scalp distribution of r-coefficients between relative SWA and prosocial preferences. The blue areas indicate negative correlations; the red areas indicate positive correlations. The white dots indicate electrodes with significant correlations (p < 0.05, corrected for multiple testing with a suprathreshold cluster analysis). The black dots indicate the position of the 59 electrodes. C, Scatterplot of the positive correlation between mean relative SWA in the significant cluster over the right TPJ and prosocial preferences (including regression line and confidence interval 95%). D, Relationship between SWA current density in the right TPJ and prosocial preferences. Locations of the voxels that showed significant correlations are indicated in red (p < 0.05, corrected) and yellow (p < 0.10, corrected).