Related Experiment Videos
Testing peripheral somatosensory neuroprostheses by recording from raccoon cortex
C J Robinson1, R D Wurster, J S Walter
1Department of Rehabilitation Science and Technology, University of Pittsburgh, PA 15260, USA.
IEEE Transactions on Rehabilitation Engineering : a Publication of the IEEE Engineering in Medicine and Biology Society
|March 1, 1997
Summary
Researchers tested a new method for evaluating somatosensory neuroprosthetic electrode arrays using raccoons. Selective nerve stimulation demonstrated the array
Area of Science:
- Neuroscience
- Biomedical Engineering
- Somatosensory System Research
Background:
- Mammalian somatosensory cortex exhibits a topographically organized representation of the body surface.
- Stimulation of specific body areas elicits responses in localized regions of the contralateral cortex.
- This topography offers a potential method for testing the selectivity of peripheral neuroprosthetic devices.
Purpose of the Study:
- To propose and test a method for evaluating the selectivity of peripheral somatosensory neuroprosthetic electrode arrays.
- To investigate the feasibility of using the raccoon as an animal model for this testing method due to its unique somatosensory cortex organization.
- To demonstrate that selective stimulation of the median nerve can produce measurable and distinct cortical responses.
Main Methods:
- A pilot study was conducted on a raccoon under anesthesia.
- A four-electrode tripolar nerve cuff array was implanted around the median nerve.
- Selective quadrants of the cuff array were used to stimulate the median nerve.
- Evoked surface potentials in the somatosensory cortex and motor responses were recorded.
Main Results:
- Short-latency evoked surface potentials were observed in the digit areas of the first somatosensory cortex following median nerve stimulation.
- Demonstrated response selectivity, indicating the array could differentiate between stimulated nerve portions.
- Showed a discernible separation between thresholds for eliciting motor responses and cortical evoked potentials.
- Sensory and motor responses correlated with the nerve's orientation within the cuff, confirmed by postmortem analysis.
Conclusions:
- The proposed method is feasible for testing the selectivity of somatosensory neuroprosthetic electrode arrays.
- The raccoon serves as a suitable model for such investigations due to its specialized cortical representation.
- Selective nerve stimulation via electrode arrays can reliably evoke specific cortical and motor responses, validating the approach for neuroprosthetic development.