Alternations in cortical thickness and functional connectivity in patients with generalized anxiety disorder

Objective To investigate the changes of cortical thickness and relative resting state functional connectivity in patients with generalized anxiety disorder (GAD). Methods The present study analyzed structural and eyes-open resting state functional MRI were performed in 21 patients with GAD and 22 matched healthy controls. Cortical thickness was estimated with FreeSurfer. The structurally altered regions were defined as region of interest (ROI) to analyze functional connectivity (FC) using resting state functional MRI data by DPABI. Results Cortical thickness of patients with GAD were increased in right rostral middle frontal gyrus (rMFG; MNI: x=27.9, y=53.4, z=-11.1; size: 241.93 mm2; FDR corrected, P<0.1) and right inferior temporal gyrus (IGT; MNI: x=49.7, y=-57.8, z=-8.7; size: 138.93 mm2; FDR corrected, P<0.1) compared with healthy controls. FC between right rMFG and right superior/middle occipital gyrus as well as well as FC between rMFG and right precentral gyrus showed decreased in patients with GAD compared with healthy controls(AlphaSim corrected, P<0.05). FC between right rMFG and right angular gyrus showed increased in patients with GAD compared with healthy control (AlphaSim corrected, P<0.05). Conclusion The rMFG may play an important role in the pathophysiology of GAD, which can be used as an stimuli target in physicotherapeutics to improve anxiety symptoms. Key words: Generalized anxiety disorder; Cortical thickness; Functional connectivity; Rostral middle frontal gyrus; Magnetic resonance imaging