Overall GMV reduction in patients with GAD (GRF correction; voxel level p < 0.001, cluster level p < 0.05) (a). Alteration tendency of the average GMV of the whole brain of GAD (b) and GMV alteration tendency of regions with significant group differences in the overall GMV of GAD (c). GMV gray matter volume, GAD generalized anxiety disorder, ITG inferior temporal gyrus, sgACC subgenual anterior cingulate cortex, vmPFC ventromedial prefrontal cortex, dmPFC dorsal medial prefrontal cortex, L left, R right.