Neural population dynamics in motor cortex are different for reach and grasp
- University of Chicago, United States
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
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Neural population dynamics in motor cortex are different for reach and graspDryad Digital Repository, doi:10.5061/dryad.xsj3tx9cm.
Article and author information
Author details
Elizaveta V Okorokova
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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Neural population dynamics in motor cortex are different for reach and grasp
eLife 9:e58848.
https://doi.org/10.7554/eLife.58848
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