Increased cerebellar-default-mode network connectivity at rest in obsessive-compulsive disorder

Area of Science:

• Neuroscience
• Psychiatry
• Medical Imaging

Background:

• Abnormalities in the cerebellum and default-mode network (DMN) are frequently observed in individuals with obsessive-compulsive disorder (OCD).
• However, the precise nature of functional connections between the cerebellum and the DMN during a resting state in OCD patients remains largely uncharacterized.

Purpose of the Study:

• To investigate the alterations in resting-state functional connectivity (FC) between the cerebellum and the DMN in patients with OCD.
• To explore the potential of these connectivity patterns as biomarkers for discriminating OCD patients from healthy controls.

Main Methods:

• Resting-state functional magnetic resonance imaging (fMRI) was conducted on 40 OCD patients and 38 healthy controls (HCs).
• Seed-based functional connectivity (FC) analysis and support vector machine (SVM) classification were employed to analyze the fMRI data.
• The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) was used to assess symptom severity.

Main Results:

• OCD patients showed increased FC between the left Crus I and the left superior medial prefrontal cortex (MPFC), and between the right Crus I and the left superior MPFC, left middle MPFC, and left middle temporal gyrus (MTG).
• A significant negative correlation was found between right Crus I-left MTG connectivity and the compulsion subscale scores of the Y-BOCS in the OCD group.
• SVM analysis, using connectivity between the left Crus I-left superior MPFC and right Crus I-left middle MPFC, achieved 76.92% accuracy in distinguishing OCD patients from HCs.

Conclusions:

• The findings underscore the significant role of cerebellar-DMN connectivity in the pathophysiology of OCD.
• Altered functional connections between the cerebellum and DMN regions represent a potential neuroimaging marker for OCD.
• This research offers novel insights into the neural underpinnings of OCD and suggests avenues for diagnostic development.