images for each condition was selected based on the peak (current density) activity in ORN and ORP components. Statistical analyses involved a voxel-wise Statistical non-Parametric Mapping (SnPM) in order to determine significant regional statistical differences in current density between two groups or conditions. The SnPM method calculates the t-values using the permutation approach and offers the exact (i.e., corrected for multiple comparisons) critical t-values [41] for each voxel. These values are calculated via a randomization method [42], and the SnPM approach controls for Type I error [43]. Since numerous voxels in each comparison were statistically significant, only few of the highly significant ones have been reported in the study.
