A Wearable Multichannel EEG/EMG Sensor System for Corticomuscular Coupling Analysis

Corticomuscular coupling (CMC) refers to the interaction between neural activity in the cerebral cortex (especially the motor cortex) and muscle activity, is an effective method for investigating the neural mechanisms of motor control. Achieving robust CMC analysis depends significantly on the fidelity of electroencephalogram (EEG) and electromyogram (EMG) signals, as well as their precise synchronization. There is a lack of integrated EEG EMG acquisition systems with high synchronization accuracy dedicated to CMC. This article proposes a sensor system integrating a 16-channel EEG module with a 16-channel EMG module. The system provides EMG/EEG signals of comparable quality to commercially available systems, with a synchronization error within nanosecond range. An isokinetic rotation experiment of the shoulder joint was implemented with EEG and EMG signals collected simultaneously. Subsequently, CMC analysis was performed using wavelet coherence. The results indicate that the CMC between the triceps brachii (TB) and the contralateral cortex is significantly higher than the CMC between the TB and the ipsilateral cortex. The CMC between the TB and the contralateral cortex exhibits notable differences across various frequency bands during both contraction and relaxation phases. These findings are consistent with the current CMC research. The proposed system facilitate CMC related research and applications in human-machine interaction such as motor assessment in post-stroke.