Brain structure in pediatric Tourette syndrome

Previous studies of brain structure in Tourette syndrome (TS) have produced mixed results, and most had modest sample sizes. In the present multi-center study, we used structural MRI to compare 103 children and adolescents with TS to a well-matched group of 103 children without tics. We applied voxel-based morphometry methods to test gray matter (GM) and white matter (WM) volume differences between diagnostic groups, accounting for MRI scanner and sequence, age, sex and total GM + WM volume. The TS group demonstrated greater GM volume in posterior thalamus, hypothalamus and midbrain, and lower WM volume bilaterally in orbital and medial prefrontal cortex. These results demonstrate evidence for abnormal brain structure in children and youth with TS, consistent with and extending previous findings. As orbital cortex is reciprocally connected with hypothalamus, our results suggest that structural abnormalities in these regions may relate to abnormal behavioral inhibition and somatic monitoring in TS.