Journal of International Psychiatry

Objective The resting-state functional magnetic resonance imaging (rs-fMRI) method was used to explore the local brain function and dynamic functionalconnection mode of patients with obsessive-compulsive disorder at rest. Methods Functional brain data was collected from OCD patients (n=50) and healthy controls (n=50) in rest. The fractional amplitude of low-frequency fluctuations (fALFF) approach was used to explore local spontaneous neural activities, dFC analysis was used to investigate the whole-brain dFC patterns at rest in patients with OCD. Partial correlation analysis was used to analyze the relationship between abnormal fALFF and dFC values and the clinical symptoms in patients with OCD. The support vector machines (SVM) was used to explore whether brain regions with abnormal function and dynamic connectivity could be used for the recognition of OCD. Results Compared with controls group, patients with OCD showed increased fALFF value in the right middle frontal gyrus (t=3.6967; P<0.05, Gaussian random field theory (GRF) corrected) and reduced fALFF value in the left superior temporal gyrus (t=-3.9716; P<0.05, GRF corrected); reduced dFC between the right middle frontal gyrus and the left lingual gyrus, and the left precuneus, and the right calcarine (t=-3.6705, -4.0795, -3.9618; P<0.01, GRF corrected). No significant correlation between abnormal fALFF and dFC values and clinical symptoms. SVM results showed that brain areas with abnormal fALFF and dFC values were not well differentiated between OCD patients and healthy controls. Conclusion The left superior temporal gyrus and the right middle frontal gyrus showed abnormal local spontaneous neural activities and whole-brain dFC at rest in patients with OCD.

Obsessive-compulsive disorder; Fractional amplitude of low-frequency fluctuations; Dynamic functional connectivity; Support vector machines