An fNIRS-Based Dynamic Functional Connectivity Analysis Method to Signify Functional Neurodegeneration of Parkinson’s Disease

Abstract

Parkinson's disease (PD) is a prevalent brain disorder, and PD diagnosis is crucial for treatment. Existing methods for PD diagnosis are mainly focused on behavior analysis, while the functional neurodegeneration of PD has not been well investigated. This paper proposes a method to signify functional neurodegeneration of PD with dynamic functional connectivity analysis. A functional near-infrared spectroscopy (fNIRS)-based experimental paradigm was designed to capture brain activation from 50 PD patients and 41 age-matched healthy controls in clinical walking tests. Dynamic functional connectivity was constructed with sliding-window correlation analysis, and k-means clustering was applied to generate the key brain connectivity states. Dynamic state features including state occurrence probability, state transition percentage and state Manuscript

Transcutaneous auricular vagus nerve stimulation enhanced emotional inhibitory control via increasing intrinsic prefrontal couplings

“…Notably, dynamic functional connectivity analyses also suggested that functional couplings (FCs) within prefrontal cortex including IFG, OFC, dlPFC and mPFC during the whole emotional inhibition task were significantly modulated by taVNS. This approach helps us quantify the experimental paradigm-based variations of brain functional networks affected by taVNS regardless of conditions ( Lu et al, 2023 ; Tang, Chong, Kiguchi, Funane & Lu, 2021 ). Among these couplings, taVNS significantly strengthened dlPFC- mPFC/ IFG/OFC/ dlPFC and OFC-IFG links in States 1, 3 and 4, suggesting that such dlPFC- and OFC- related functional couplings played a primary role in taVNS effects on emotional inhibitory processes.…”

“…Dynamic functional connectivity was constructed using a sliding-window correlation analysis, and k-means clustering was applied to generate the key brain connectivity states under taVNS and sham conditions, respectively ( Lu et al, 2023 ) , for more details see in SI. Then, treatment groups were compared on FCs within each state using independent t tests with permutations for multiple comparisons ( Camargo, Azuaje, Wang & Zheng, 2008 ; Nichols & Holmes, 2002 ) .…”

Transcutaneous auricular vagus nerve stimulation enhanced inhibitory control via increasing intrinsic prefrontal couplings

“…Notably, dynamic functional connectivity analyses also suggested that functional couplings (FCs) within prefrontal cortex including IFG, OFC, dlPFC and mPFC during the whole emotional inhibition task were significantly modulated by taVNS. This approach helps us quantify the experimental paradigm-based variations of brain functional networks affected by taVNS regardless of conditions (Tang et al ., 2021; Lu et al ., 2023). Among these couplings, taVNS significantly strengthened dlPFC-mPFC/ IFG/OFC/ dlPFC and OFC-IFG links in States1, 3 and 4, suggesting that such dlPFC- and OFC-related functional couplings played primary role in taVNS effects on emotional inhibitory processes.…”

“…This approach helps us quantify the experimental paradigm-based variations of brain functional networks affected by taVNS regardless of conditions (Tang et al, 2021;Lu et al, 2023). Among these couplings, taVNS significantly strengthened dlPFC-mPFC/ IFG/OFC/ dlPFC and OFC-IFG links in States1, 3 and 4, suggesting that such dlPFC-and OFC-related functional couplings played primary role in taVNS effects on emotional inhibitory processes.…”

“…Dynamic functional connectivity was constructed using a sliding-window correlation analysis, and k-means clustering was applied to generate the key brain connectivity states under taVNS and sham conditions, respectively (Tang et al ., 2021; Lu et al ., 2023). Firstly, dynamic functional connectivity analysis using the sliding window method (window length: 252 data points, ∼37.1s) was conducted based on time series of HbO data from a total of 30 channels per participant to investigate the transient functional coupling (FC) within prefrontal regions during the whole emotional Go/No-Go task.…”