Motor memories of object dynamics are categorically organized

  1. Evan Cesanek  Is a corresponding author
  2. Zhaoran Zhang
  3. James N Ingram
  4. Daniel M Wolpert
  5. J Randall Flanagan
  1. Columbia University, United States
  2. Queen's University, Canada

Abstract

The ability to predict the dynamics of objects, linking applied force to motion, underlies our capacity to perform many of the tasks we carry out on a daily basis. Thus, a fundamental question is how the dynamics of the myriad objects we interact with are organized in memory. Using a custom-built three-dimensional robotic interface that allowed us to simulate objects of varying appearance and weight, we examined how participants learned the weights of sets of objects that they repeatedly lifted. We find strong support for the novel hypothesis that motor memories of object dynamics are organized categorically, in terms of families, based on covariation in their visual and mechanical properties. A striking prediction of this hypothesis, supported by our findings and not predicted by standard associative map models, is that outlier objects with weights that deviate from the family-predicted weight will never be learned despite causing repeated lifting errors.

Data availability

All source data, analysis code, and figure generation code is available in the supplementary files.

Article and author information

Author details

  1. Evan Cesanek

    Department of Neuroscience, Columbia University, New York, United States
    For correspondence
    evan.cesanek@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5335-6604
  2. Zhaoran Zhang

    Department of Neuroscience, Columbia University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. James N Ingram

    Department of Neuroscience, Columbia University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Daniel M Wolpert

    Department of Neuroscience, Columbia University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2011-2790
  5. J Randall Flanagan

    Centre for Neuroscience Studies, Queen's University, Kingston, Canada
    Competing interests
    The authors declare that no competing interests exist.

Funding

No external funding was received for this work.

Ethics

Human subjects: All experiments were conducted in accordance with the 1964 Declaration of Helsinki, following protocol approved by the Columbia University Institutional Review Board (IRB-AAAR9148). Written informed consent was obtained from all participants prior to their participation.

Copyright

© 2021, Cesanek 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. Evan Cesanek
  2. Zhaoran Zhang
  3. James N Ingram
  4. Daniel M Wolpert
  5. J Randall Flanagan
(2021)
Motor memories of object dynamics are categorically organized
eLife 10:e71627.
https://doi.org/10.7554/eLife.71627

Share this article

https://doi.org/10.7554/eLife.71627

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