Perception of microstimulation frequency in human somatosensory cortex
- University of Pittsburgh, United States
- Stanford University, United States
Abstract
Microstimulation in the somatosensory cortex can evoke artificial tactile percepts and can be incorporated into bidirectional brain-computer interfaces (BCIs) to restore function after injury or disease. However, little is known about how stimulation parameters themselves affect perception. Here, we stimulated through microelectrode arrays implanted in the somatosensory cortex of two human participants with cervical spinal cord injury and varied the stimulus amplitude, frequency and train duration. Increasing the amplitude and train duration increased the perceived intensity on all tested electrodes. Surprisingly, we found that increasing the frequency evoked more intense percepts on some electrodes but evoked less intense percepts on other electrodes. These different frequency-intensity relationships were divided into three groups which also evoked distinct percept qualities at different stimulus frequencies. Neighboring electrode sites were more likely to belong to the same group. These results support the idea that stimulation frequency directly controls tactile perception and that these different percepts may be related to the organization of somatosensory cortex, which will facilitate principled development of stimulation strategies for bidirectional BCIs.
Data availability
Data and code for this paper are available at GitHub (https://github.com/chughes003r/FrequencyPaper)
Article and author information
Author details
Christopher L Hughes
Michael L Boninger
Jennifer Collinger
Funding
Defense Advanced Research Projects Agency (N66001-16-C4051)
- Michael L Boninger
- Jennifer Collinger
- Robert Gaunt
National Institutes of Health (UH3NS107714)
- Michael L Boninger
- Jennifer Collinger
- Robert Gaunt
National Institutes of Health (U01NS108922)
- Michael L Boninger
- Jennifer Collinger
- Robert Gaunt
National Science Foundation (DGE-1247842)
- Sharlene N Flesher
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: This study was conducted under an Investigational Device Exemption from the U.S. Food and Drug administration, approved by the Institutional Review Boards at the University of Pittsburgh (Pittsburgh, PA) and the Space and Naval Warfare Systems Center Pacific (San Diego, CA), and registered at ClinicalTrials.gov (NCT0189-4802). Informed consent was obtained before any study procedures were conducted.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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Perception of microstimulation frequency in human somatosensory cortex
eLife 10:e65128.
https://doi.org/10.7554/eLife.65128
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