1. Neuroscience
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Unusual prism adaptation reveals how grasping is controlled

  1. Willemijn D Schot  Is a corresponding author
  2. Eli Brenner  Is a corresponding author
  3. Jeroen BJ Smeets  Is a corresponding author
  1. Vrije Universiteit Amsterdam, Netherlands
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Cite this article as: eLife 2017;6:e21440 doi: 10.7554/eLife.21440

Abstract

There are three main theories on how human grasping movements are controlled. Two of them state that grip aperture and the movement of the hand are controlled. They differ in whether the wrist or the thumb of the hand is controlled. We have proposed a third theory, which states that grasping is a combination of two goal-directed single-digit movements, each directed at a specific position on the object. In this study, we test predictions based on each of the theories by examining the transfer of prism adaptation during single-digit pointing movements to grasping movements. We show that adaptation acquired during single-digit movements transfers to the hand opening when subsequently grasping objects, leaving the movement of the hand unaffected. Our results provide strong evidence for our theory that grasping with the thumb and index finger is based on a combination of two goal-directed single-digit movements.

Article and author information

Author details

  1. Willemijn D Schot

    Department of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
    For correspondence
    W.D.Schot@uu.nl
    Competing interests
    The authors declare that no competing interests exist.
  2. Eli Brenner

    Department of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
    For correspondence
    E.Brenner@vu.nl
    Competing interests
    The authors declare that no competing interests exist.
  3. Jeroen BJ Smeets

    Department of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
    For correspondence
    J.B.J.Smeets@vu.nl
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3794-0579

Funding

Nederlandse Organisatie voor Wetenschappelijk Onderzoek (453-08-004)

  • Jeroen BJ Smeets

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

Ethics

Human subjects: This study was part of a research programme that has been approved by the Ethische Commissie Bewegingswetenschappen (ECB 2006-02). All participants gave their informed consent before participating in this study.

Reviewing Editor

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

Publication history

  1. Received: September 11, 2016
  2. Accepted: September 9, 2017
  3. Accepted Manuscript published: September 11, 2017 (version 1)
  4. Version of Record published: September 28, 2017 (version 2)

Copyright

© 2017, Schot 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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