Altered intrinsic brain functional network dynamics in drug-naïve Parkinson's disease patients with excessive daytime sleepiness

Motivation: Excessive daytime sleepiness (EDS) is a frequent nonmotor symptoms in Parkinson's disease (PD) patients. Previous studies on EDS used static analyses that ignored the temporal evolution of resting-state functional magnetic resonance imaging signals. Goal(s): This study aimed to identify dynamic functional network connectivity (dFNC) characteristics in PD with EDS (PD-EDS) patients. Approach: The sliding window approach, k-means clustering and independent component analysis were applied to estimate dFNC parameters. Results: The PD-EDS patients showed increased fractional time and mean dwell time in state IV. The strong connectivity within and between the sensorimotor and visual network was related to EDS in PD patients. Impact: Our research provided new insights into the neural mechanisms underlying PD patients with EDS. The alterations of dynamic functional connectivity may serve as biomarkers of the pathophysiological features of PD with EDS patients.