Measuring Kolmogorov entropy of EEG for studying the state of mental fatigue

Abstract

Kolmogorov entropy reflects the chaotic degree of the system. In this paper, the chaotic degree of EEG under different mental fatigue states was measured. Analyzing the relationship between different mental fatigue states and the corresponding Kolmogorov entropy (KE) of EEG, it was shown: (1) the value of KE was strongly correlative with the mental fatigue state; the corresponding value of mean Kolmogorov entropy (KE) for a special mental state fluctuated within the special range; (2) the values of KE decreased with working times prolonged; (3) it is available to differentiate different mental fatigue level objectively according to the value of KE. The method proposed in this paper is expected to provide a new tool for the efforts of evaluating mental fatigue level objectively and the study of effects of mental fatigue on central neural system.