EEG-EMG signal processing and analysis for the neuromuscular activity patterns with three motion modes under two time intervals

To address the issue that how the EEG-EMG signals change according to different motion modes, an experiment was conducted on ten subjects with three tasks performing the voluntary, stimulated and imaginary finger flexion activities. The experiment was set two programs including 10s and 2s time intervals. Electroencephalogram (EEG) from C3/C4 channels and electromyogram (EMG) from flexor digitorum superficialis were recorded simultaneously. Besides the threshold detection of wave peaks between two points, morlet wavlet-based time-frequency analysis was adopted to study the independent variation mechanisms between EEG and EMG under different motion modes. The results indicated that EMG signals of 2s intervals exhibited a similar trend with 10s intervals. The EMG energy increased over 50 Hz when actions occurred. On the contrary, there were no significant changes in imaginary task. In addition, EEG signals performed obviously different. No pronounced similar changes were found in 10s and 2s intervals. Finally, the results demonstrated that EEG-EMG causality was high during 2s intervals in stimulation task. © (2013) Trans Tech Publications, Switzerland.