1. Neuroscience
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Systematic examination of low-intensity ultrasound parameters on human motor cortex excitability and behaviour

  1. Anton Fomenko  Is a corresponding author
  2. Kai-Hsiang Stanley Chen
  3. Jean-François Nankoo
  4. James Saravanamuttu
  5. Yanqiu Wang
  6. Mazen El-Baba
  7. Xue Xia
  8. Shakthi Sanjana Seerala
  9. Kullervo Hynynen
  10. Andres M Lozano  Is a corresponding author
  11. Robert Chen  Is a corresponding author
  1. University of Toronto, Canada
  2. National Taiwan University, Taiwan
  3. Toronto Western Hospital, Canada
  4. Sunnybrook Research Institute, Canada
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Cite this article as: eLife 2020;9:e54497 doi: 10.7554/eLife.54497

Abstract

Low-intensity transcranial ultrasound (TUS) can non-invasively modulate human neural activity. We investigated how different fundamental sonication parameters influence the effects of TUS on the motor cortex (M1) of 16 healthy subjects by probing cortico-cortical excitability and behaviour. A low-intensity 500 kHz TUS transducer was coupled to a transcranial magnetic stimulation (TMS) coil. TMS was delivered 10 ms before the end of TUS to the left M1 hotspot of the first dorsal interosseous muscle. Varying acoustic parameters (pulse repetition frequency, duty cycle and sonication duration) on motor-evoked potential amplitude were examined. Paired-pulse measures of cortical inhibition and facilitation, and performance on a visuomotor task was also assessed. TUS safely suppressed TMS-elicited motor cortical activity, with longer sonication durations and shorter duty cycles when delivered in a blocked paradigm. TUS increased GABAA-mediated short-interval intracortical inhibition and decreased reaction time on visuomotor task but not when controlled with TUS at near-somatosensory threshold intensity.

Data availability

Data used for this study are included in the manuscript and supporting files.Files for 3D printing the stimulating devices and custom MATLAB scripts used for stimulation have been deposited into a cited GitHub repository.

Article and author information

Author details

  1. Anton Fomenko

    Krembil Research Institute, University of Toronto, Toronto, Canada
    For correspondence
    anton.fomenko@uhnresearch.ca
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4131-6784

  2. Kai-Hsiang Stanley Chen

    Neurology, National Taiwan University, Taiwan, Taiwan
    Competing interests
    The authors declare that no competing interests exist.

  3. Jean-François Nankoo

    Krembil Research Institute, University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.

  4. James Saravanamuttu

    Krembil Research Institute, University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.

  5. Yanqiu Wang

    Krembil Research Institute, University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.

  6. Mazen El-Baba

    Krembil Research Institute, University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.

  7. Xue Xia

    Toronto Western Hospital, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.

  8. Shakthi Sanjana Seerala

    Focused Ultrasound Group, Sunnybrook Research Institute, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.

  9. Kullervo Hynynen

    Focused Ultrasound Group, Sunnybrook Research Institute, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.

  10. Andres M Lozano

    Krembil Research Institute, University of Toronto, Toronto, Canada
    For correspondence
    lozano@uhnresearch.ca
    Competing interests
    The authors declare that no competing interests exist.

  11. Robert Chen

    Toronto Western Hospital, Toronto, Canada
    For correspondence
    robert.chen@uhn.ca
    Competing interests
    The authors declare that no competing interests exist.

Funding

Canadian Institutes of Health Research (Banting and Best Doctoral Award)

  • Anton Fomenko

Canadian Institutes of Health Research (Foundation Grant,FDN 154292)

  • Robert Chen

University of Manitoba (Clinician Investigator Program)

  • Anton Fomenko

Canada Research Chairs (Neuroscience)

  • Andres M Lozano

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 patients gave written informed consent and the protocol was approved by the UHN Research Ethics Board (Protocol #18-5082) in accordance with the Declaration of Helsinki on the use of human subjects in experiments.

Reviewing Editor

  1. Laura Dugué, Uni­ver­sité de Paris, France

Publication history

  1. Received: December 16, 2019
  2. Accepted: November 24, 2020
  3. Accepted Manuscript published: November 25, 2020 (version 1)
  4. Version of Record published: December 10, 2020 (version 2)

Copyright

© 2020, Fomenko 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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