Related Experiment Video
Updated: May 31, 2026
05:21
Characterization of the Sense of Agency over the Actions of Neural-machine Interface-operated Prostheses
Published on: January 7, 2019
A novel command signal for motor neuroprosthetic control
Christa W Moss1, Kevin L Kilgore, P Hunter Peckham
1Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA. caw30@case.edu
Neurorehabilitation and Neural Repair
|June 23, 2011
Summary
Voluntary muscle activity is detectable below the injury level in individuals with spinal cord injury (SCI). This finding supports using these muscles as command signals for neuroprostheses, potentially restoring function.
Area of Science:
- Neuroscience
- Biomedical Engineering
- Rehabilitation Medicine
Background:
- Neuroprostheses use electrical stimulation to restore function in spinal cord injury (SCI) patients.
- Current systems rely on electromyographic (EMG) signals from muscles above the lesion.
- Advanced neuroprostheses require additional command signals, especially for high-level SCI.
Purpose of the Study:
- Investigate the feasibility of using muscles below the SCI as command sources for neuroprostheses.
- Explore EMG activity in muscles with intact, yet non-functional, axons across the lesion.
Main Methods:
- Recorded surface EMG from 8 lower leg muscles in 12 participants with motor complete SCI.
- Analyzed EMG activity during attempted foot and lower limb movements.
Main Results:
- Significant EMG activity was found in 89% of studied muscles.
- At least two muscles per participant were identified as potential neuroprosthesis command signals.
Conclusions:
- Voluntary activity is present and recordable in muscles below the lesion, even in clinically complete SCI.
- This demonstrates the potential for novel neuroprosthetic control strategies.
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