A critical re-evaluation of fMRI signatures of motor sequence learning
Abstract
Despite numerous studies, there is little agreement about what brain changes accompany motor sequence learning, partly because of a general publication bias that favors novel results. We therefore decided to systematically reinvestigate proposed functional magnetic resonance imaging correlates of motor learning in a preregistered longitudinal study with four scanning sessions over 5 weeks of training. Activation decreased more for trained than untrained sequences in premotor and parietal areas, without any evidence of learning-related activation increases. Premotor and parietal regions also exhibited changes in the fine-grained, sequence-specific activation patterns early in learning, which stabilized later. No changes were observed in the primary motor cortex (M1). Overall, our study provides evidence that human motor sequence learning occurs outside of M1. Furthermore, it shows that we cannot expect to find activity increases as an indicator for learning, making subtle changes in activity patterns across weeks the most promising fMRI correlate of training-induced plasticity.
Data availability
fMRI data and analysis pipelines have been deposted to OpenNeuro, under the accession number ds002776. Analysis code is available on GitHub at https://github.com/eberlot/motor_sequence_learning.git
Article and author information
Author details
Funding
Natural Sciences and Engineering Research Council of Canada (NSERC Discovery Grant (RGPIN-2016-04890))
- Jörn Diedrichsen
Canada First Research Excellence Fund (BrainsCAN)
- Jörn Diedrichsen
Ontario Trillium Foundation (Graduate Student Scholarship (to EB))
- Jörn Diedrichsen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Informed consent and data usage agreement was obtained from participants prior to the onset of the study. It was emphasized that participants could withdraw from the study at any timepoint. The experimental procedures were approved by the Ethics Committee at Western University (HSREB File Number: 107061).
Copyright
© 2020, Berlot 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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