Abstract

To date there exists no reliable method to non-invasively upregulate or downregulate the state of the resting human motor system over a large dynamic range. Here we show that an operant conditioning paradigm which provides neurofeedback of the size of motor evoked potentials (MEPs) in response to transcranial magnetic stimulation (TMS), enables participants to self-modulate their own brain state. Following training, participants were able to robustly increase (by 83.8%) and decrease (by 30.6%) their MEP amplitudes. This volitional up-versus downegulation of corticomotor excitability caused an increase of late-cortical disinhibition (LCD), a TMS derived read-out of presynaptic GABAB disinhibition, which was accompanied by an increase of gamma and a decrease of alpha oscillations in the trained hemisphere. This approach paves the way for future investigations into how altered brain state influences motor neurophysiology and recovery of function in a neurorehabilitation context.

Data availability

Data are openly available on the ETH Library Research Collection with the DOI: https://doi.org/10.3929/ethz-b-000300799.This contains processed EEG data for all subjects (Figure 5), EMG data and MEPs from the main experiment (Figure 2) and follow-up experiments (Figures 3 and 4).

The following data sets were generated

Article and author information

Author details

  1. Kathy Ruddy

    Neural Control of Movement Lab, ETH, Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5501-0423
  2. Joshua Balsters

    Neural Control of Movement Lab, ETH, Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9856-6990
  3. Dante Mantini

    Neural Control of Movement Lab, ETH, Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6485-5559
  4. Quanying Liu

    Neural Control of Movement Lab, ETH, Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2501-7656
  5. Pegah Kassraian-Fard

    Neural Control of Movement Lab, ETH, Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6562-7918
  6. Nadja Enz

    Neural Control of Movement Lab, ETH, Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2476-4710
  7. Ernest Mihelj

    Neural Control of Movement Lab, ETH, Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6080-2553
  8. Bankim Subhash Chander

    Applied Neurotechnology Laboratory, University of Tübingen, Tübingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3206-8822
  9. Surjo R Soekadar

    Applied Neurotechnology Laboratory, University of Tübingen, Tübingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1280-5538
  10. Nicole Wenderoth

    Neural Control of Movement Lab, ETH, Zürich, Zürich, Switzerland
    For correspondence
    nicole.wenderoth@hest.ethz.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3246-9386

Funding

Swiss National Science Foundation (320030_175616)

  • Nicole Wenderoth

Irish Research Council (GOIPD/2017/798)

  • Kathy Ruddy

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Human subjects: All participants gave written informed consent to procedures. The experiments were approved by the Kantonale Ethikkommission Zürich, and were conducted in accordance with the Declaration of Helsinki (1964).

Copyright

© 2018, Ruddy 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. Kathy Ruddy
  2. Joshua Balsters
  3. Dante Mantini
  4. Quanying Liu
  5. Pegah Kassraian-Fard
  6. Nadja Enz
  7. Ernest Mihelj
  8. Bankim Subhash Chander
  9. Surjo R Soekadar
  10. Nicole Wenderoth
(2018)
Neural activity related to volitional regulation of cortical excitability
eLife 7:e40843.
https://doi.org/10.7554/eLife.40843

Share this article

https://doi.org/10.7554/eLife.40843

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