After these preprocessing steps, whole-brain analyses with a statistical threshold of p < 0.05, family-wise error whole-brain corrected with 10 contiguous voxels were employed to identify brain regions activated by the positive feedback > negative feedback contrast. The bilateral maximal voxels in whole brain analyses, which were within the VS, exhibiting a main effect of task were extracted using the volume of interest tool in SPM8 and imported into SPSS (SPSS Inc., USA) for further analyses. Extracting parameter estimates activated by our paradigm, rather than voxels specifically correlated with our independent variables of interest, precludes the possibility of any regression coefficient inflation that may result from capitalizing on the same data twice (Viviani, 2010). This conservative strategy has been used in previous reports (Bogdan et al. 2012).
