Abnormal structure and function of white matter in obsessive-compulsive disorder

Area of Science:

• Neuroimaging
• Neuroscience
• Psychiatry

Background:

• Gray matter (GM) abnormalities are known in the cortico-striatal-thalamic-cortical (CSTC) circuit in obsessive-compulsive disorder (OCD).
• White matter (WM) integrity is crucial for GM function, necessitating investigation in OCD.

Purpose of the Study:

• To explore WM structure and function in patients with OCD.
• To investigate the relationship between WM alterations and clinical symptoms.
• To assess the diagnostic potential of WM changes in OCD.

Main Methods:

• Diffusion tensor imaging (DTI) and resting-state functional magnetic resonance imaging (rs-fMRI) were used.
• Tract-based spatial statistics (TBSS) and amplitude of low-frequency fluctuations (ALFF) analyzed WM structure and function.
• Structural-functional coupling and support vector machine (SVM) evaluated relationships and diagnostic capability.

Main Results:

• OCD patients exhibited lower fractional anisotropy (FA) in several WM tracts and reduced ALFF/FA ratio in the left anterior thalamic radiation (ATR).
• Decreased functional connectivity between the left ATR and left dorsal lateral prefrontal cortex was observed.
• Reduced ALFF/FA ratio in the left ATR correlated with OCD and anxiety symptom severity. SVM achieved 0.80 accuracy in distinguishing OCD from HCs.

Conclusions:

• This study reveals significant alterations in WM structure and function in OCD.
• Abnormal WM structural-functional coupling may contribute to aberrant GM connectivity within the CSTC circuit.
• WM changes show potential as biomarkers for OCD diagnosis.