Poor self-control in personality inventory and reduced volume of supplementary motor area

The present study provides evidence for a relationship between schizophrenia-related personality and brain morphometry. The brain magnetic resonance imaging (MRI) and schizophrenia-related personality scales extracted from the Minnesota Multiphasic Personality Inventory (MMPI) were administered to 42 university students. The gray matter segmented from the MR images on a voxel-by-voxel basis was compared between the high- and low-score groups based on the schizophrenia-related measures. This analysis revealed that the subjects with high tendency to the lack of self-control in the subscales had a reduced gray matter density in the supplementary motor area (SMA). Furthermore, it was suggested that self-control including self-inhibition is associated with the density of the SMA, the precuneus and cerebellar vermis that govern voluntary movements and motor imagery. These results provide important clues to the neural basis for the disturbance of self that are associated with schizophrenia spectrum disorders.