A Myoelectric Computer Interface for Reducing Abnormal Muscle Activations after Spinal Cord Injury

Area of Science:

• Neuroscience
• Rehabilitation Engineering
• Biomedical Engineering

Background:

• Spinal cord injury (SCI) and other neurological disorders often lead to impaired motor function and abnormal muscle activation patterns.
• Compensatory strategies and undesired co-contraction can hinder motor recovery after neurological damage.
• Myoelectric Computer Interfaces (MCIs) offer a potential avenue for restoring movement and improving muscle control.

Purpose of the Study:

• To develop and test an MCI designed to reduce abnormal muscular activations, specifically co-contraction and compensatory strategies, in individuals with SCI.
• To investigate the efficacy of mapping surface electromyographic (sEMG) signals to cursor movement for motor control.
• To assess the impact of modulated visual feedback on reducing undesired muscle activation.

Main Methods:

• Development of an MCI system that translates sEMG signals into cursor movements on a computer monitor.
• Implementation of strategies to reduce muscle pair co-activation and modulate visual feedback based on third muscle activation.
• Testing the MCI with six unimpaired participants and two participants with SCI.

Main Results:

• Participants demonstrated an ability to decrease targeted muscle activity when linked to visual cursor feedback, though activity increased again after training.
• One SCI participant successfully reduced arm muscle co-activation.
• Another SCI participant improved selective leg muscle activation.
• This study serves as a proof of concept for MCIs enhancing muscle awareness and reducing simultaneous muscle activations in SCI individuals.

Conclusions:

• The developed MCI system shows potential for improving motor control and reducing abnormal muscle activation in individuals with SCI.
• MCIs can enhance proprioceptive feedback, leading to greater awareness of muscular activity.
• This technology represents a promising tool for rehabilitation after SCI, facilitating better selective muscle control.