Direction-dependent arm kinematics reveal optimal integration of gravity cues

  1. Jeremie Gaveau  Is a corresponding author
  2. Bastien Berret
  3. Dora E Angelaki
  4. Charalambos Papaxanthis
  1. Université Bourgogne Franche-Comté, INSERM CAPS UMR 1093, France
  2. CIAMS, Université Paris-Sud, Université Paris Saclay, France
  3. Baylor College of Medicine, United States

Abstract

The brain has evolved an internal model of gravity to cope with life in the Earth's gravitational environment. How this internal model benefits the implementation of skilled movement has remained unsolved. One prevailing theory has assumed that this internal model is used to compensate for gravity's mechanical effects on the body, such as to maintain invariant motor trajectories. Alternatively, gravity force could be used purposely and efficiently for the planning and execution of voluntary movements, thereby resulting in direction-depending kinematics. Here we experimentally interrogate these two hypotheses by measuring arm kinematics while varying movement direction in normal and zero-G gravity conditions. By comparing experimental results with model predictions, we show that the brain uses the internal model to implement control policies that take advantage of gravity to minimize movement effort.

Article and author information

Author details

  1. Jeremie Gaveau

    Université Bourgogne Franche-Comté, INSERM CAPS UMR 1093, Dijon, France
    For correspondence
    jeremie.gaveau@u-bourgogne.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8827-1486
  2. Bastien Berret

    CIAMS, Université Paris-Sud, Université Paris Saclay, Orsay, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Dora E Angelaki

    Department of Neuroscience, Baylor College of Medicine, Houston, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9650-8962
  4. Charalambos Papaxanthis

    Université Bourgogne Franche-Comté, INSERM CAPS UMR 1093, Dijon, France
    Competing interests
    The authors declare that no competing interests exist.

Funding

Institut National de la Santé et de la Recherche Médicale

  • Jeremie Gaveau
  • Charalambos Papaxanthis

Agence Nationale de la Recherche (projet MOTION, 14-CE30-007-01)

  • Charalambos Papaxanthis

National Institute of Neurological Disorders and Stroke (R21-NS-075944-02)

  • Jeremie Gaveau
  • Dora E Angelaki
  • Charalambos Papaxanthis

Centre National d'Etudes Spatiales

  • Jeremie Gaveau
  • Bastien Berret
  • Charalambos Papaxanthis

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, and consent to publish, was obtained from all participants. The regional ethics committee of Burgundy (C.E.R) and the ethics committee of INSERM (Institut National de la Santé et de la Recherche Médicale) approved experimental protocols. All procedures were carried out in agreement with local requirements and international norms (Declaration of Helsinki, 1964).

Copyright

© 2016, Gaveau 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. Jeremie Gaveau
  2. Bastien Berret
  3. Dora E Angelaki
  4. Charalambos Papaxanthis
(2016)
Direction-dependent arm kinematics reveal optimal integration of gravity cues
eLife 5:e16394.
https://doi.org/10.7554/eLife.16394

Share this article

https://doi.org/10.7554/eLife.16394

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