Homogeneous grey matter patterns in patients with obsessive-compulsive disorder

Area of Science:

• Neuroimaging
• Neuroscience
• Psychiatry

Background:

• Obsessive-compulsive disorder (OCD) is associated with changes in grey matter volume.
• Previous studies focused on whole-brain or region-of-interest analyses.
• Investigating grey matter volume within structural covariance networks in OCD is underexplored.

Purpose of the Study:

• To investigate grey matter volume within structural covariance networks in OCD patients compared to healthy controls.
• To determine if network-related grey matter volume can differentiate OCD patients.
• To explore associations between grey matter organization and clinical characteristics.

Main Methods:

• Independent Component Analysis (ICA) to derive morphometric networks from T1 images.
• Extraction and comparison of grey matter volume within ICA-derived networks.
• Logistic regression and ROC analyses for diagnostic discrimination.
• Assessment of grey matter pattern organization and correlation with clinical data.

Main Results:

• Subtle group differences in network-related grey matter volume were observed.
• Network-related grey matter volume showed poor discrimination performance.
• Significant differences in grey matter pattern organization were found: higher homogeneity and lower heterogeneity in OCD patients.
• No association between grey matter metrics and clinical characteristics.

Conclusions:

• Pathological mechanisms in OCD appear to reduce interindividual grey matter variability.
• Common characteristics of OCD may lead to more uniform, disorder-specific morphometry.
• Grey matter pattern organization, rather than volume, may be a key neurobiological feature of OCD.