Evaluating variability of frequency features of EEG signals during mental fatigue

The brain regions involved in variation of mind activity from attention to mental fatigue are considered to reduce the number of recording EEG channels for detecting brain activities. In this study, subjects performed a visual attentive task for about 45 minutes without rest and during task, EEG signals, subjective levels of fatigue and performance measures were recorded. Frequency features of EEG signals extracted by using spectrogram and discrete wavelet were transformed to distinguish different levels of mental fatigue and they were used to determine effective channels that represent fatigue in subjects.