Competition between parallel sensorimotor learning systems
- Johns Hopkins School of Medicine, United States
- York University, Canada
- University of Buenos Aires, Argentina
- Johns Hopkins University School of Medicine, United States
Abstract
Sensorimotor learning is supported by at least two parallel systems: a strategic process that benefits from explicit knowledge, and an implicit process that adapts subconsciously. How do these systems interact? Does one system's contributions suppress the other, or do they operate independently? Here we illustrate that during reaching, implicit and explicit systems both learn from visual target errors. This shared error leads to competition such that an increase in the explicit system's response siphons away resources that are needed for implicit adaptation, thus reducing its learning. As a result, steady-state implicit learning can vary across experimental conditions, due to changes in strategy. Furthermore, strategies can mask changes in implicit learning properties, such as its error sensitivity. These ideas, however, become more complex in conditions where subjects adapt using multiple visual landmarks, a situation which introduces learning from sensory prediction errors in addition to target errors. These two types of implicit errors can oppose each other, leading to another type of competition. Thus, during sensorimotor adaptation, implicit and explicit learning systems compete for a common resource: error.
Data availability
Source data files generated or analyzed during this study, as well as the associated analysis code, are included as supplements to Figures 1-10, as well as their associated Figure Supplements, and have also been deposited in OSF under accession code MZS6A
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Competition between parallel sensorimotor learning systemsOSF, Doi 10.17605/OSF.IO/MZS6A.
Article and author information
Author details
Funding
National Institute of Neurological Disorders and Stroke (F32NS095706)
- Scott T Albert
National Science Foundation (CNS-1714623)
- Reza Shadmehr
National Institute of Neurological Disorders and Stroke (R01NS078311)
- Reza Shadmehr
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 was obtained from all study participants. All human subjects work was approved by the Johns Hopkins School of Medicine Institutional Review Board (protocol number NA_00037510) or the York Human Participants Review Sub-committee.
Copyright
© 2022, 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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Competition between parallel sensorimotor learning systems
eLife 11:e65361.
https://doi.org/10.7554/eLife.65361
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