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High-fidelity musculoskeletal modeling reveals that motor planning variability contributes to the speed-accuracy tradeoff
A long-standing challenge in motor neuroscience is to understand the relationship between movement speed and accuracy, known as the speed-accuracy tradeoff. Here, we introduce a biomechanically realistic computational model of three-dimensional upper extremity movements that reproduces well-known fe...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
eLife Sciences Publications, Ltd
2020
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7787661/ https://www.ncbi.nlm.nih.gov/pubmed/33325369 http://dx.doi.org/10.7554/eLife.57021 |
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author | Al Borno, Mazen Vyas, Saurabh Shenoy, Krishna V Delp, Scott L |
author_facet | Al Borno, Mazen Vyas, Saurabh Shenoy, Krishna V Delp, Scott L |
author_sort | Al Borno, Mazen |
collection | PubMed |
description | A long-standing challenge in motor neuroscience is to understand the relationship between movement speed and accuracy, known as the speed-accuracy tradeoff. Here, we introduce a biomechanically realistic computational model of three-dimensional upper extremity movements that reproduces well-known features of reaching movements. This model revealed that the speed-accuracy tradeoff, as described by Fitts’ law, emerges even without the presence of motor noise, which is commonly believed to underlie the speed-accuracy tradeoff. Next, we analyzed motor cortical neural activity from monkeys reaching to targets of different sizes. We found that the contribution of preparatory neural activity to movement duration (MD) variability is greater for smaller targets than larger targets, and that movements to smaller targets exhibit less variability in population-level preparatory activity, but greater MD variability. These results propose a new theory underlying the speed-accuracy tradeoff: Fitts’ law emerges from greater task demands constraining the optimization landscape in a fashion that reduces the number of ‘good’ control solutions (i.e., faster reaches). Thus, contrary to current beliefs, the speed-accuracy tradeoff could be a consequence of motor planning variability and not exclusively signal-dependent noise. |
format | Online Article Text |
id | pubmed-7787661 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | eLife Sciences Publications, Ltd |
record_format | MEDLINE/PubMed |
spelling | pubmed-77876612021-01-11 High-fidelity musculoskeletal modeling reveals that motor planning variability contributes to the speed-accuracy tradeoff Al Borno, Mazen Vyas, Saurabh Shenoy, Krishna V Delp, Scott L eLife Neuroscience A long-standing challenge in motor neuroscience is to understand the relationship between movement speed and accuracy, known as the speed-accuracy tradeoff. Here, we introduce a biomechanically realistic computational model of three-dimensional upper extremity movements that reproduces well-known features of reaching movements. This model revealed that the speed-accuracy tradeoff, as described by Fitts’ law, emerges even without the presence of motor noise, which is commonly believed to underlie the speed-accuracy tradeoff. Next, we analyzed motor cortical neural activity from monkeys reaching to targets of different sizes. We found that the contribution of preparatory neural activity to movement duration (MD) variability is greater for smaller targets than larger targets, and that movements to smaller targets exhibit less variability in population-level preparatory activity, but greater MD variability. These results propose a new theory underlying the speed-accuracy tradeoff: Fitts’ law emerges from greater task demands constraining the optimization landscape in a fashion that reduces the number of ‘good’ control solutions (i.e., faster reaches). Thus, contrary to current beliefs, the speed-accuracy tradeoff could be a consequence of motor planning variability and not exclusively signal-dependent noise. eLife Sciences Publications, Ltd 2020-12-16 /pmc/articles/PMC7787661/ /pubmed/33325369 http://dx.doi.org/10.7554/eLife.57021 Text en © 2020, Al Borno et al http://creativecommons.org/licenses/by/4.0/ http://creativecommons.org/licenses/by/4.0/This article is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use and redistribution provided that the original author and source are credited. |
spellingShingle | Neuroscience Al Borno, Mazen Vyas, Saurabh Shenoy, Krishna V Delp, Scott L High-fidelity musculoskeletal modeling reveals that motor planning variability contributes to the speed-accuracy tradeoff |
title | High-fidelity musculoskeletal modeling reveals that motor planning variability contributes to the speed-accuracy tradeoff |
title_full | High-fidelity musculoskeletal modeling reveals that motor planning variability contributes to the speed-accuracy tradeoff |
title_fullStr | High-fidelity musculoskeletal modeling reveals that motor planning variability contributes to the speed-accuracy tradeoff |
title_full_unstemmed | High-fidelity musculoskeletal modeling reveals that motor planning variability contributes to the speed-accuracy tradeoff |
title_short | High-fidelity musculoskeletal modeling reveals that motor planning variability contributes to the speed-accuracy tradeoff |
title_sort | high-fidelity musculoskeletal modeling reveals that motor planning variability contributes to the speed-accuracy tradeoff |
topic | Neuroscience |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7787661/ https://www.ncbi.nlm.nih.gov/pubmed/33325369 http://dx.doi.org/10.7554/eLife.57021 |
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