Attenuated brain white matter functional network interactions in Parkinson's disease

Area of Science:

• Neuroscience
• Medical Imaging
• Neurology

Background:

• Parkinson's disease (PD) involves structural brain abnormalities, but functional network changes in brain white matter (BWM) are not well understood.
• Resting-state functional magnetic resonance imaging (rs-fMRI) can reveal neuronal activity within BWM.

Purpose of the Study:

• To investigate alterations in BWM functional network interactions in Parkinson's disease patients compared to healthy controls.
• To explore the relationship between BWM functional network changes and clinical symptoms of PD.

Main Methods:

• Sixty-eight PD patients and sixty-three healthy controls (HC) underwent rs-fMRI scans.
• Twelve BWM functional networks were identified using K-means clustering and analyzed for interactions via Granger causality analysis.
• Functional interactions were examined across deep, middle, and superficial BWM layers.

Main Results:

• PD patients exhibited significantly weaker functional interaction strength within BWM networks compared to HC.
• Attenuated excitatory influences from superficial to deep networks and inhibitory influences from deep to superficial networks were observed in PD.
• Reduced overall functional interaction strength in tri-layered BWM networks was found in PD patients (p < .05).
• Functional interactions involving deep BWM networks negatively correlated with Unified Parkinson's Disease Rating Scale (UPDRS) Part III and Hamilton Depression Scale scores.

Conclusions:

• Parkinson's disease is associated with attenuated BWM functional network interactions.
• These BWM abnormalities correlate with both motor and non-motor symptoms in PD.
• Findings enhance understanding of PD neuropathology and nervous system progression from a BWM functional perspective.