Postural control of arm and fingers through integration of movement commands
- Johns Hopkins School of Medicine, United States
- Columbia University Medical Center, United States
- Newcastle University, United Kingdom
Abstract
Every movement ends in a period of stillness. Current models assume that commands that hold the limb at a target location do not depend on the commands that moved the limb to that location. Here, we report a surprising relationship between movement and posture in primates: on a within-trial basis, the commands that hold the arm and finger at a target location depend on the mathematical integration of the commands that moved the limb to that location. Following damage to the corticospinal tract, both the move and hold period commands become more variable. However, the hold period commands retain their dependence on the integral of the move period commands. Thus, our data suggest that the postural controller possesses a feedforward module that uses move commands to calculate a component of hold commands. This computation may arise within an unknown subcortical system that integrates cortical commands to stabilize limb posture.
Data availability
Source data files generated or analyzed during this study are included for Figures 1-7 and have also been deposited in OSF under accession code YC64A.
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Postural control of arm and fingers through integration of movement commands.Open Science Framework, doi:10.17605/OSF.IO/YC64A.
Article and author information
Author details
Funding
National Institute of Neurological Disorders and Stroke (R01NS078311)
- Reza Shadmehr
Sheikh Khalifa Stroke Institute
- John W Krakauer
Medical Research Council (MR/K023012/1)
- Demetris S Soteropoulos
National Institute of Neurological Disorders and Stroke (1DP2NS083037)
- Mark M Churchland
National Institute of Neurological Disorders and Stroke (R01NS100066)
- Mark M Churchland
National Institute of Neurological Disorders and Stroke (1U19NS104649)
- Mark M Churchland
National Institute of Neurological Disorders and Stroke (F31NS095706)
- Scott T Albert
National Institute of Neurological Disorders and Stroke (F32NS092350)
- Mark M Churchland
National Science Foundation (1723967)
- Reza Shadmehr
Simons Foundation (SCGB#542957)
- Mark M Churchland
Medical Research Council (MR/P023967)
- Stuart N Baker
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 animal procedures in the U.S. were conducted in accord with the US National Institutes of Health guidelines and were approved by the Columbia University Institutional Animal Care and Use Committee (AC-AAAQ7409). These data were originally published in Lara, Cunningham, & Churchland (2018) as well as Lara, Elsayed, Zimnik, Cunningham, & Churchland (2018). All procedures in the U.K. were carried out under appropriate UK Home Office licenses in accordance with the Animals (Scientific Procedures) Act 1986, and were approved by the Local Research Ethics Committee of Newcastle University. These data were originally published in Soteropoulos, Williams, & Baker (2012).
Human subjects: Informed consent was obtained from all participants. All human subjects work was approved by the Johns Hopkins School of Medicine Institutional Review Board, protocol number NA_00037510.
Copyright
© 2020, Albert 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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Postural control of arm and fingers through integration of movement commands
eLife 9:e52507.
https://doi.org/10.7554/eLife.52507
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