Analysis of Brain Functional Network Based on EEG Signals for Early-Stage Parkinson’s Disease Detection

Wei Zhang,Xiao Shen,Liufang Wang,Zhen Li,Rui Zhang,Zhuo Li,Chen Liu,Lipeng Bai,Teng Li,Zhen Zhang,Manyi Yang,Jiang Wang,Xiaodong Zhu,Yanlin Wang,Ruixian Wang,Shujuan Qiu,Chunguang Chu,Xiaoxuan Han

doi:10.1109/access.2022.3150561

Abstract

The early diagnosis of Parkinson’s disease (PD) has always been a difficult problem to be solved clinically. At present, there is no clinical auxiliary diagnostic index for reference. We attempted to extract potential biomarkers for early PD from the currently used scalp EEG detection methods in clinical practice. We calculated the phase synchronization index to quantify the synchrony of EEG channels in various frequency bands (delta, theta, alpha and beta bands) of early PD. The results showed that the synchronization of early PD in the delta band was significantly lower than the healthy level, and the brain region reflecting the lower synchronization was located in the temporal lobe, the posterior temporal lobe, the parietal lobe (the posterior center) and the occipital lobe. Moreover, this lower synchronicity is consistent with weaker brain functional connections. Besides, by constructing functional brain network, the graph theoretic topological features of each frequency band of early PD are presented. We have found that early PD has characteristics of small world network in the delta and beta bands, and functional integration and separation characteristics of brain network in early PD are significantly abnormal in the delta, theta, alpha and beta bands. These results indicate that early PD has significant pathological changes from the perspective of brain function network analysis, and its characteristics can be described by multiple features, which may provide auxiliary guidance for the clinical diagnosis of early PD, and also provide theoretical support for the brain function changes of early PD.

Highlights

P ARKINSON’S disease (PD) is a chronic neurodegenerative disorder without pathologic treatment, characterized by motor symptoms and non-motor symptoms [1]– [3]
In order to study whether the synchronization level of brain activity in patients with early PD has a state that is typically different from the healthy level, we calculated the average parameters of phase lag index (PLI)-based synchronization matrix of 29 patients with early PD and 22 healthy subjects respectively
It is evident that the synchronization level of early PD in the delta band is lower than healthy level, indicating that there is abnormal synchronization of brain activity in early PD

Summary

Introduction

P ARKINSON’S disease (PD) is a chronic neurodegenerative disorder without pathologic treatment, characterized by motor symptoms (resting tremor, bradykinesia, rigidity and abnormal gait) and non-motor symptoms (depression, anxiety, cognitive decline, etc.) [1]– [3]. Patients usually need to seek treatment after 50 to 80% of the Substantia Nigra pars compacta (SNc) has been destroyed [4]. This suggests that the destructive process of SNc begins several years before the diagnosis of the early stage of PD, and with the progressive development of the disease course, the PD patient will gradually lose the corresponding function, and reach the stage of disability. Early-stage clinical diagnosis plays a key role in the control of the progression of PD and the delay of its disabling stage. It is an urgent problem to find out the significant biomarker of early PD, and the reliable biomarker will be an excellent auxiliary index to reduce the clinical misdiagnosis rate.

Methods

Results

Discussion

Conclusion