Consolidation alters motor sequence-specific distributed representations
Abstract
FMRI studies investigating the acquisition of sequential motor skills in humans have revealed learning-related functional reorganizations of the cortico-striatal and cortico-cerebellar motor systems accompanied with an initial hippocampal contribution. Yet, the functional significance of these activity level changes remains ambiguous as they convey the evolution of both sequence-specific knowledge and unspecific task ability. Moreover, these changes do not specifically assess the occurrence of learning-related plasticity. To address these issues, we investigated local circuits tuning to sequence-specific information using multivariate distances between patterns evoked by consolidated or newly acquired motor sequences production. The results reveal that representations in dorsolateral striatum, prefrontal and secondary motor cortices are greater when executing consolidated sequences than untrained ones. By contrast, sequence representations in the hippocampus and dorsomedial striatum becomes less engaged. Our findings show, for the first time in humans, that complementary sequence-specific motor representations evolve distinctively during critical phases of skill acquisition and consolidation.
Data availability
Behavioral data analyzed and presented in the article as well as statistical maps of brain representational measure have been deposited on the Open Science Framework with the DOI 10.17605/OSF.IO/EPJ2V
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Consolidation alters motor sequence-specific distributed representationsOpen Science Framework, DOI 10.17605/OSF.IO/EPJ2V.
Article and author information
Author details
Funding
Canadian Institutes of Health Research (MOP 97830)
- Basile Pinsard
- Arnaud Boutin
- Ella Gabitov
- Julien Doyon
Ministère de l'Education Nationale, de l'Enseignement Superieur et de la Recherche (PhD scholarship)
- Basile Pinsard
Sorbonne Université (PhD study abroad grant)
- Basile Pinsard
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: All participants provided written informed consent and received financial compensationfor their participation. This study protocol was approved by the Research Ethics Board of the ""Comité mixte d'éthique de la recherche - Regroupement en Neuroimagerie duQuébec"" (CMER-RNQ 13-14-011).
Copyright
© 2019, Pinsard 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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