Abstract

Low-dimensional linear dynamics are observed in neuronal population activity in primary motor cortex (M1) when monkeys make reaching movements. This population-level behavior is consistent with a role for M1 as an autonomous pattern generator that drives muscles to give rise to movement. In the present study, we examine whether similar dynamics are also observed during grasping movements, which involve fundamentally different patterns of kinematics and muscle activations. Using a variety of analytical approaches, we show that M1 does not exhibit such dynamics during grasping movements. Rather, the grasp-related neuronal dynamics in M1 are similar to their counterparts in somatosensory cortex, whose activity is driven primarily by afferent inputs rather than by intrinsic dynamics. The basic structure of the neuronal activity underlying hand control is thus fundamentally different from that underlying arm control.

Data availability

The data that support the findings of this study have been deposited in Dryad, accessible at https://doi.org/10.5061/dryad.xsj3tx9cm

The following data sets were generated

Article and author information

Author details

  1. Aneesha K Suresh

    Computational Neuroscience, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. James M Goodman

    Computational Neuroscience, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Elizaveta V Okorokova

    Computational Neuroscience, University 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:" 0000-0002-2719-2706
  4. Matthew Kaufman

    Department of Oganismal Biology and Anatomy, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Nicholas G Hatsopoulos

    Department of Organismal Biology and Anatomy, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Sliman J Bensmaia

    Organismal Biology and Anatomy, University of Chicago, Chicago, United States
    For correspondence
    sliman@uchicago.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4039-9135

Funding

National Institute of Neurological Disorders and Stroke (NS082865)

  • Nicholas G Hatsopoulos
  • Sliman J Bensmaia

National Institute of Neurological Disorders and Stroke (NS096952)

  • Aneesha K Suresh

National Institute of Neurological Disorders and Stroke (NS045853)

  • Nicholas G Hatsopoulos

National Institute of Neurological Disorders and Stroke (NS111982)

  • Nicholas G Hatsopoulos

National Institute of Neurological Disorders and Stroke (NS101325)

  • Sliman J Bensmaia

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

Ethics

Animal experimentation: All surgical, behavioral, and experimental procedures conformed to the guidelines of the National Institutes of Health and were approved by the University of Chicago Institutional Animal Care and Use Committee (#72042).

Copyright

© 2020, Suresh 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. Aneesha K Suresh
  2. James M Goodman
  3. Elizaveta V Okorokova
  4. Matthew Kaufman
  5. Nicholas G Hatsopoulos
  6. Sliman J Bensmaia
(2020)
Neural population dynamics in motor cortex are different for reach and grasp
eLife 9:e58848.
https://doi.org/10.7554/eLife.58848

Share this article

https://doi.org/10.7554/eLife.58848

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