Down regulation of vestibular balance stabilizing mechanisms to enable transition between motor states

  1. Romain Tisserand
  2. Christopher J Dakin  Is a corresponding author
  3. Machiel HF Van der Loos
  4. Elizabeth A Croft
  5. Timothy J Inglis
  6. Jean-Sebastien Blouin
  1. University of British Columbia, Canada
  2. Utah State University, United States
  3. Monash University, Australia

Abstract

The neural control of transition between posture and movement encompasses the regulation of reflex-stabilizing mechanisms to enable motion. Optimal feedback theory suggests that such transitions require the disengagement of one motor control policy before the implementation of another. To test this possibility, we investigated the continuity of the vestibular control of balance during transitions between quiet standing and locomotion and between two standing postures. Healthy subjects initiated and terminated locomotion or shifted the distribution of their weight between their feet, while exposed to electrical vestibular stimuli (EVS). The relationship between EVS and ground reactions forces was quantified using time-frequency analyses. Discontinuities corresponding to null coherence periods were observed preceding the onset of movement initiation and during the step preceding locomotion termination. These results show humans interrupt the vestibular balance stabilizing mechanisms to transition between motor states, suggesting a discrete change between motor control policies, as predicted by optimal feedback theory.

Data availability

The time-frequency coherence analysis codes (Matlab) and the statistical analysis code (R) are provided and the anonymized human data are maintained on a University of British Columbia file server. This data sharing interface requires that the link to the dataset be changed regularly for security reasons. As such, a current link to the data is available through a request to Jean-Sébastien Blouin at jsblouin@mail.ubc.ca

Article and author information

Author details

  1. Romain Tisserand

    School of Kinesiology, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6857-9886
  2. Christopher J Dakin

    Department of Kinesiology and Health Science, Utah State University, Logan, United States
    For correspondence
    chris.dakin@usu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6781-0281
  3. Machiel HF Van der Loos

    Department of Mechanical Engineering, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  4. Elizabeth A Croft

    Department of Engineering, Monash University, Victoria, Australia
    Competing interests
    The authors declare that no competing interests exist.
  5. Timothy J Inglis

    School of Kinesiology, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  6. Jean-Sebastien Blouin

    School of Kinesiology, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.

Funding

Natural Sciences and Engineering Research Council of Canada (356026)

  • Jean-Sebastien Blouin

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

Ethics

Human subjects: Informed consent of participating to this study and publishing the results in a scientific journal was obtained from all participants.Ethical approval was obtained from the University of British Columbia Clinical Research Ethics under the identifiant H09-00987. Application was approved by Suzanne Richardson.

Copyright

© 2018, Tisserand 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. Romain Tisserand
  2. Christopher J Dakin
  3. Machiel HF Van der Loos
  4. Elizabeth A Croft
  5. Timothy J Inglis
  6. Jean-Sebastien Blouin
(2018)
Down regulation of vestibular balance stabilizing mechanisms to enable transition between motor states
eLife 7:e36123.
https://doi.org/10.7554/eLife.36123

Share this article

https://doi.org/10.7554/eLife.36123

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