Analysis of EEG Microstates During Execution of a Nine Hole Peg Test

Abstract

Abstract—EEG microstates are brief periods of time during which the brain’s electrical activity remains stable. The analysis of EEG microstates can help to identify the background neuronal activity at the millisecond level. The main objective of this study is to observe changes in brain microstates by varying demand during different experiment phases, involving a fatiguing exercise. The hypothesis explored in this paper is that resting state and fine motor states involve different neural assemblies and that physical fatigue induced using a wrist dumbbell flexion/extension exercise impacts these microstates. An experiment is conducted with 5 healthy participants, exploring this. Three distinct microstates are observed during the resting state and a separate set of 3 states are observed during the Nine Hole Peg Test. Changes are assessed by utilising microstate parameters such as occurrence, coverage, duration, and global explained variance. It is found that the coverage of microstate C for resting states decreases for all the participants after the dumbbell exercise. During the fine-motor task, the coverage of microstate MS3 decreases for all participants except one. These results support the involvement of different neural assemblies, but also highlight the potential that physical fatigue can be observed and identified by assessing changes in microstate features, in this case, a parameter such as coverage.