Modulation of Myoelectric Activity by a Virtual Interface of a Prosthetic Hand

A virtual interface of a prosthetic hand was developed to serve as a training system for amputees. In the present study, the effectiveness of the interface in modulating myoelectric activity was evaluated by cross-correlation and phase difference between the sinusoid commands to the fingers of the virtual prosthesis and the high-density electromyogram (HD EMG) recorded from the forearm muscles of healthy participants. The results showed a strong correlation between the command and the RMS signals from the HD EMG, mainly when the command signal was at 0.50 Hz. The delay between command and EMG modulation did not exceed 700 ms, which is compatible with the expected delay caused by visuomotor processing and action. Therefore, the virtual interface demonstrated its capability to modulate the neuromuscular system across various tasks and could be helpful in training amputees to control the finger movements of a prosthetic device.