Targeted cortical reorganization using optogenetics in non-human primates

  1. Azadeh Yazdan-Shahmorad  Is a corresponding author
  2. Daniel B Silversmith  Is a corresponding author
  3. Viktor Kharazia
  4. Philip N Sabes
  1. University of California, San Francisco, United States

Abstract

Brain stimulation modulates the excitability of neural circuits and drives neuroplasticity. While the local effects of stimulation have been an active area of investigation, the effects on large-scale networks remain largely unexplored. We studied stimulation-induced changes in network dynamics in two macaques. A large-scale optogenetic interface enabled simultaneous stimulation of excitatory neurons and electrocorticographic recording across primary somatosensory (S1) and motor (M1) cortex (Yazdan-Shahmorad et al., 2016). We tracked two measures of network connectivity, the network response to focal stimulation and the baseline coherence between pairs of electrodes; these were strongly correlated before stimulation. Within minutes, stimulation in S1 or M1 significantly strengthened the gross functional connectivity between these areas. At a finer scale, stimulation led to heterogeneous connectivity changes across the network. These changes reflected the correlations introduced by stimulation-evoked activity, consistent with Hebbian plasticity models. This work extends Hebbian plasticity models to large-scale circuits, with significant implications for stimulation-based neurorehabilitation.

Data availability

We have provided the numerical data (.mat format) for all of the graphs in all of the figures except where images or raw data were presented. For each figure we are providing ReadMe files that include descriptions of the parameters used as well as the Matlab code for generating the figures. In addition, we have made the full dataset available via UCSF data share program: https://dash.berkeley.edu/stash/dataset/doi:10.7272/Q61834NF

The following data sets were generated

Article and author information

Author details

  1. Azadeh Yazdan-Shahmorad

    Department of Physiology, University of California, San Francisco, San Francisco, United States
    For correspondence
    azadehy@uw.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5212-509X
  2. Daniel B Silversmith

    Center for Integrative Neuroscience, University of California, San Francisco, San Francisco, United States
    For correspondence
    dsilversmith@berkeley.edu
    Competing interests
    No competing interests declared.
  3. Viktor Kharazia

    Center for Integrative Neuroscience, University of California, San Francisco, San Francisco, United States
    Competing interests
    No competing interests declared.
  4. Philip N Sabes

    Department of Physiology, University of California, San Francisco, San Francisco, United States
    Competing interests
    Philip N Sabes, has financial interest in Neuralink Corp., a company that is developing clinical therapies using brain stimulation.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8397-6225

Funding

Defense Advanced Research Projects Agency (W911NF-14-2-0043)

  • Azadeh Yazdan-Shahmorad
  • Daniel B Silversmith
  • Viktor Kharazia
  • Philip N Sabes

American Heart Association (Post-doctoral fellowship)

  • Azadeh Yazdan-Shahmorad

National Science Foundation (Graduate student fellowship)

  • Daniel B Silversmith

This research was partially funded by the Defense Advanced Research Projects Agency (DARPA) under Cooperative Agreement Number W911NF-14-2-0043, issued by the Army Research Office contracting office in support of DARPA'S SUBNETS program. The views, opinions, and/or findings expressed are those of the author(s) and should not be interpreted as representing the official views or policies of the Department of Defense or the U.S. Government. The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: All procedures were performed under the approval of the University of California, San Francisco Institutional Animal Care and Use Committee (AN108552-03) and were compliant with the Guide for the Care and Use of Laboratory Animals.

Reviewing Editor

  1. Charles E Schroeder, Columbia University College of Physicians and Surgeons, United States

Publication history

  1. Received: August 6, 2017
  2. Accepted: May 5, 2018
  3. Accepted Manuscript published: May 29, 2018 (version 1)
  4. Version of Record published: June 4, 2018 (version 2)

Copyright

© 2018, Yazdan-Shahmorad et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Azadeh Yazdan-Shahmorad
  2. Daniel B Silversmith
  3. Viktor Kharazia
  4. Philip N Sabes
(2018)
Targeted cortical reorganization using optogenetics in non-human primates
eLife 7:e31034.
https://doi.org/10.7554/eLife.31034
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