Altered network homogeneity of the default-mode network in drug-naive obsessive - compulsive disorder

Background: Default-mode network (DMN) plays a key role in the pathophysiology of obsessive - compulsive disorder (OCD). However, the network homogeneity (NH) of DMN in OCD remains equivocal. Objective: This study aimed to investigate abnormalities in the NH of the DMN at rest and the correlation between the NH of DMN and clinical variables in patients with OCD. Methods: This study used the independent component analysis and unbiased hypothesis-driven NH method to analyze the resting-state functional magnetic resonance imaging data of 40 drug-naive patients with OCD and 40 age-, gender-, and education-matched healthy controls (HCs). Results: Patients with OCD exhibited decreased NH values in the left ventral medial prefrontal cortex and bilateral posterior cingulate cortex (PCC)/precuneus (PCu) compared with HCs. Furthermore, analyses of receiver operating characteristic curves indicated that the decreased NH values in the right PCC/PCu may be used as a candidate neuroimaging marker to distinguish patients with OCD from HCs. Conclusion: These findings contribute new evidence of the participation of the altered NH of the DMN in the pathophysiology of OCD.