Sensorimotor integration within the primary motor cortex by selective nerve fascicle stimulation
Federico Ranieri1, Giovanni Pellegrino2, Anna Lisa Ciancio3
1Unit of Neurology, Department of Neuroscience Biomedicine and Movement Sciences, University of Verona, Verona, Italy.
The Journal of Physiology
|December 18, 2021
Summary
Selective sensory nerve stimulation in amputees activates sensory cortex and inhibits motor cortex output, mimicking natural sensorimotor integration for better prosthesis control.
Area of Science:
- Neuroscience
- Biomedical Engineering
- Rehabilitation Medicine
Background:
- Cortical integration of sensory input is essential for precise motor control and dexterous movements.
- Previous research showed intraneural sensory feedback improved prosthesis manipulation and embodiment in an amputee.
- Understanding the cortical impact of selective sensory stimulation is key for advanced neuroprosthetics.
Purpose of the Study:
- To determine if selective intraneural sensory stimulation elicits measurable cortical activation in humans.
- To investigate the effects of selective intraneural sensory stimulation on sensorimotor cortical circuits.
- To compare the sensorimotor effects of intraneural sensory stimulation versus whole-nerve stimulation.
Main Methods:
- Assessed primary somatosensory cortex (S1) activation using scalp somatosensory evoked potentials after intraneural stimulation.
- Investigated sensorimotor integration by measuring the inhibition of primary motor cortex (M1) output via transcranial magnetic stimulation.
- Stimulated median and ulnar nerves using intraneural multichannel electrodes in an upper limb amputee.
Main Results:
- Selective intraneural sensory stimulation evoked a low-amplitude, 16 ms-latency response in the parietal cortex (S1).
- Intraneural sensory stimulation decreased M1 output, demonstrating short-latency afferent inhibition similar to whole-nerve stimulation.
- Stimulation of sensory-only fibers produced stronger M1 inhibition than stimulation of mixed-fiber channels.
Conclusions:
- Selective intraneural sensory stimulation in humans activates the primary somatosensory cortex.
- This stimulation effectively inhibits motor cortex output, indicating preserved sensorimotor integration.
- Findings support the use of selective intraneural stimulation for more naturalistic sensory feedback in prosthetic devices.
Keywords:
evoked potentialsintraneural double-sided filament electrodes (ds-FILE)short-latency afferent inhibitionsomatosensory peripheral stimulationtranscranial magnetic stimulation (TMS)More Related Videos
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