Magnetoencephalography detects phase-amplitude coupling in Parkinson's disease

Area of Science:

• Neuroscience
• Biophysics
• Medical Imaging

Background:

• Abnormal phase-amplitude coupling (PAC) in the cortico-basal ganglia circuit is a known characteristic of Parkinson's disease (PD).
• The presence and distribution of PAC in other brain regions in PD remain largely uncharacterized.

Purpose of the Study:

• To investigate whether whole-brain phase-amplitude coupling (PAC) can characterize Parkinson's disease (PD).
• To compare PAC patterns between PD patients and healthy controls using magnetoencephalography (MEG).

Main Methods:

• Resting-state MEG signals were recorded from PD patients and age/sex-matched healthy controls.
• Whole-brain signals were analyzed for power spectra in alpha, beta, and gamma bands.
• Phase-amplitude coupling between gamma amplitude and alpha or beta phases was evaluated.

Main Results:

• Patients with PD exhibited widespread beta-gamma PAC in sensorimotor, occipital, and temporal cortices, unlike healthy controls.
• Significant differences in beta and gamma band power were observed between the groups.
• Beta-gamma PAC in sensorimotor cortices significantly correlated with PD motor symptoms.

Conclusions:

• Resting-state beta-gamma phase-amplitude coupling is a potential biomarker for characterizing Parkinson's disease.
• This widespread PAC pattern offers a novel approach to understanding PD pathophysiology beyond the cortico-basal ganglia circuit.