Paper Title
New Method to Visualize Mental Fatigue- Electroencephalogram
Abstract
Objective physiological methods for monitoring/evaluating mental fatigue (MF) are a prerequisite to
understanding and alleviating MF. A physiological measurement and a subjective questionnaire (respectively an
electroencephalogram (EEG) and a NASA-TLX rating scale) evaluate mental fatigue induced by mental arithmetic
performed on a computer for 120 minutes. Three fatigue measurement sessions are performed: one immediately before (BT),
one immediately after (AT), and one 60 minutes after (60-min AT) the mental arithmetic task. NASA-TLX test data is
captured before each EEG test. Each EEG data collection session lasts 20 minutes, with 5 minutes at rest for EEG power
indices and 15 minutes for event-related potential (ERP) collection using a modified flanker task. Subjects appear
significantly mentally fatigued two hours after the arithmetic task. After 60 minutes of rest, the EEG power index at the
occipital recording site fails to diminish participant fatigue to the original state, except in the visual area. The EEG results
show 60-min rest post-MF-task allows full recovery only in the visual area; while ERP results reveal that MF is
characterized by temporal prolongation of cognitive information processing as well as decreased attention levels. This
method is potentially applicable to the evaluation and management of worker mental fatigue as regards occupational risk and
productivity.
Keywords - Mental fatigue, Visual cognition task, Electroencephalogram, Event-related potential.