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Energy exchanges at contact events guide sensorimotor integration across intermodal delays

  1. Ali Farshchian  Is a corresponding author
  2. Alessandra Sciutti
  3. Assaf Pressman
  4. Ilana Nisky
  5. Ferdinando A Mussa-Ivaldi
  1. Northwestern University, United States
  2. Rehabilitation Institute of Chicago, United States
  3. Ben-Gurion University of the Negev, Israel
Research Article
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Cite this article as: eLife 2018;7:e32587 doi: 10.7554/eLife.32587

Abstract

The brain must consider the arm's inertia to predict the arm's movements elicited by commands impressed upon the muscles. Here, we present evidence suggesting that the integration of sensory information leading to the representation of the arm's inertia does not take place continuously in time but only at discrete transient events, in which kinetic energy is exchanged between the arm and the environment. We used a visuomotor delay to induce cross-modal variations in state feedback and uncovered that the difference between visual and proprioceptive velocity estimations at isolated collision events was compensated by a change in the representation of arm inertia. The compensation maintained an invariant estimate across modalities of the expected energy exchange with the environment. This invariance captures different types of dysmetria observed across individuals following prolonged exposure to a fixed intermodal temporal perturbation and provides a new interpretation for cerebellar ataxia.

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Author details

  1. Ali Farshchian

    Department of Biomedical Engineering, Northwestern University, Chicago, United States
    For correspondence
    a-farshchiansadegh@northwestern.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9321-0944

  2. Alessandra Sciutti

    Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1056-3398

  3. Assaf Pressman

    Department of Biomedical Engineering, Ben-Gurion University of the Negev, Be'er-Sheva, Israel
    Competing interests
    The authors declare that no competing interests exist.

  4. Ilana Nisky

    Department of Biomedical Engineering, Ben-Gurion University of the Negev, Be'er-Sheva, Israel
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4128-9771

  5. Ferdinando A Mussa-Ivaldi

    Department of Biomedical Engineering, Northwestern University, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5343-7052

Funding

National Science Foundation (1632259)

  • Ferdinando A Mussa-Ivaldi

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

Ethics

Human subjects: The study protocol was approved by Northwestern University's Institutional Review Board (STU00026226) and all the participants signed an informed consent form.

Reviewing Editor

  1. Richard Ivry, University of California, Berkeley, United States

Publication history

  1. Received: October 7, 2017
  2. Accepted: May 13, 2018
  3. Accepted Manuscript published: May 29, 2018 (version 1)
  4. Version of Record published: June 1, 2018 (version 2)

Copyright

© 2018, Farshchian 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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