Neuroanatomical deficits in drug-naïve adult patients with generalized social anxiety disorder: a voxel-based morphometry study.

Little is known, so far, about the cerebral structural deficits in drug-naïve adult social anxiety disorder (SAD) patients. The present study aimed to explore the cerebral anatomic deficits in drug-naïve adult generalized SAD patients using voxel-based morphometric analysis with DARTEL. High-resolution T1-weighted images were acquired from 20 drug-naïve adult SAD patients and 19 age-, sex- and education-matched controls. The volumes of gray matter, white matter, cerebrospinal fluid, and total intracranial volume were compared between groups using two-sample t-tests with age and gender as covariates. Gray matter density (GMD) was compared between groups using voxel-wise two-sample t-test analysis. Correlation analysis was used to identify any associations between regional GMD and clinical symptoms. Compared with healthy controls, SAD patients showed significantly lower GMD in the bilateral thalami, right amygdala, and right precuneus. Furthermore, the GMD in the right amygdala was negatively related to the disease duration, but positively correlated with age of onset. Our findings demonstrated that cerebral anatomic deficits could be found within limbic and thalamic areas in drug-naïve SAD patients, which provides structural information to complement the functional alterations observed in the same regions.