Brain network alterations in cervical dystonia: Evidence based on graph theory analysis

Area of Science:

• Neuroscience
• Clinical Neurology
• Brain Network Analysis

Background:

• Cervical dystonia (CD) is the most common focal dystonia, understood as a brain network disorder.
• Specific brain regions implicated in CD pathophysiology require further elucidation.
• This study employs a data-driven approach to pinpoint aberrant brain regions in CD.

Purpose of the Study:

• To identify abnormal brain regions associated with cervical dystonia (CD).
• To investigate functional connectivity (FC) and network topology in CD patients compared to healthy controls (HC).
• To explore the relationship between brain network alterations and clinical severity in CD.

Main Methods:

• Electroencephalography (EEG) data acquired from 16 CD patients and 15 HC.
• Source localization applied to map EEG signals to the cerebral cortex.
• Functional connectivity (FC) quantified using weighted phase lag index (wPLI) across five frequency bands.
• Network-Based Statistics (NBS) and graph theory analyzed network topology.
• Correlations assessed between network metrics and clinical severity scores.

Main Results:

• CD patients exhibited widespread brain network alterations across multiple frequency bands compared to HC.
• Decreased FC in the alpha band suggests impaired motor control.
• Increased FC in beta and low gamma bands indicates sensory processing and cortical inhibition abnormalities.
• Caudate nucleus node strength emerged as a potential biomarker for CD severity.
• A distinct modular structure involving the thalamus and sensorimotor cortex was observed in the beta band, indicating aberrant sensory-motor integration.

Conclusions:

• The study reveals novel insights into the pathophysiological mechanisms of cervical dystonia.
• Findings highlight specific brain network alterations in CD, particularly in sensory-motor integration.
• These results are crucial for advancing diagnostic and therapeutic strategies for CD.