Electroencephalographic Functional Connectivity With the Tacit Learning System Prosthetic Hand: A Case Series Using...

Area of Science:

• Neuroscience
• Biomedical Engineering
• Rehabilitation Medicine

Background:

• A novel prosthetic hand incorporates a tacit learning system (TLS) for automated forearm pronosupination control.
• This myoelectric prosthesis offers sensory feedback and adaptable motor output, aiming to reduce user burden and enhance movement efficiency.

Purpose of the Study:

• To investigate the influence of the TLS's auxiliary function on brain activity using electroencephalography (EEG).
• To analyze differences in cortical activity during motor imagery with and without TLS activation in below-elbow amputees.

Main Methods:

• Three male participants with below-elbow amputations and myoelectric prosthesis experience underwent EEG recording.
• Participants imagined performing physical movements while viewing videos of themselves with TLS inactivated and activated.
• Cortical current and amplitude envelope correlation (AEC) between supplementary motor areas (SMA) and vertex were analyzed.

Main Results:

• Significant differences in mean cortical current were observed between TLS inactivated and activated conditions during motor imagery.
• Amplitude envelope correlation (AEC) values were higher with TLS activation, indicating increased neural coupling.
• Increased AEC values were noted in somatosensory cortex (S1) and other brain regions when the TLS was active.

Conclusions:

• The tacit learning system (TLS) appears to modulate brain activity beyond basic motor control.
• Evidence suggests the TLS may also influence sensory stimulus recognition in users of myoelectric prostheses.
• This case series provides preliminary insights into the neurophysiological impact of advanced prosthetic control systems.