Dataset Information

Complex Upper-Limb Movements Are Generated by Combining Motor Primitives that Scale with the Movement Size.

ABSTRACT: The hand trajectory of motion during the performance of one-dimensional point-to-point movements has been shown to be marked by motor primitives with a bell-shaped velocity profile. Researchers have investigated if motor primitives with the same shape mark also complex upper-limb movements. They have done so by analyzing the magnitude of the hand trajectory velocity vector. This approach has failed to identify motor primitives with a bell-shaped velocity profile as the basic elements underlying the generation of complex upper-limb movements. In this study, we examined upper-limb movements by analyzing instead the movement components defined according to a Cartesian coordinate system with axes oriented in the medio-lateral, antero-posterior, and vertical directions. To our surprise, we found out that a broad set of complex upper-limb movements can be modeled as a combination of motor primitives with a bell-shaped velocity profile defined according to the axes of the above-defined coordinate system. Most notably, we discovered that these motor primitives scale with the size of movement according to a power law. These results provide a novel key to the interpretation of brain and muscle synergy studies suggesting that human subjects use a scale-invariant encoding of movement patterns when performing upper-limb movements.

SUBMITTER: Miranda JGV

PROVIDER: S-EPMC6110807 | biostudies-other | 2018 Aug

REPOSITORIES: biostudies-other

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Complex Upper-Limb Movements Are Generated by Combining Motor Primitives that Scale with the Movement Size.

Miranda Jose Garcia Vivas JGV Daneault Jean-François JF Vergara-Diaz Gloria G Torres Ângelo Frederico Souza de Oliveira E ÂFSOE Quixadá Ana Paula AP Fonseca Marcus de Lemos ML Vieira João Paulo Bomfim Cruz JPBC Dos Santos Vitor Sotero VS da Figueiredo Thiago Cruz TC Pinto Elen Beatriz EB Peña Norberto N Bonato Paolo P

Scientific reports 20180827 1

The hand trajectory of motion during the performance of one-dimensional point-to-point movements has been shown to be marked by motor primitives with a bell-shaped velocity profile. Researchers have investigated if motor primitives with the same shape mark also complex upper-limb movements. They have done so by analyzing the magnitude of the hand trajectory velocity vector. This approach has failed to identify motor primitives with a bell-shaped velocity profile as the basic elements underlying ...[more]

PMID: 30150687

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Dataset Information

Complex Upper-Limb Movements Are Generated by Combining Motor Primitives that Scale with the Movement Size.

Publications

Complex Upper-Limb Movements Are Generated by Combining Motor Primitives that Scale with the Movement Size.

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