Although the 47,XXY group performed as well as controls, they were found to have a lower mean lateralization index across all the ROIs, driven primarily by differences in the STG and supramarginal gyrus. Similar to the SPECT results mentioned earlier, the loss of lateralization was due to increased language-related activity in the right hemisphere compared with controls. Examination of the relationship of measures of psychopathology with the brain activation data found that a higher total PANSS score correlated with decreased lateralization, and that evidence of more disorganized thoughts on the SPQ correlated with decreased functional lateralization in the STG.
