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Invariant errors reveal limitations in motor correction rather than constraints on error sensitivity.

ABSTRACT: Implicit sensorimotor adaptation is traditionally described as a process of error reduction, whereby a fraction of the error is corrected for with each movement. Here, in our study of healthy human participants, we characterize two constraints on this learning process: the size of adaptive corrections is only related to error size when errors are smaller than 6°, and learning functions converge to a similar level of asymptotic learning over a wide range of error sizes. These findings are problematic for current models of sensorimotor adaptation, and point to a new theoretical perspective in which learning is constrained by the size of the error correction, rather than sensitivity to error.

SUBMITTER: Kim HE

PROVIDER: S-EPMC6123629 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Invariant errors reveal limitations in motor correction rather than constraints on error sensitivity.

Kim Hyosub E HE Morehead J Ryan JR Parvin Darius E DE Moazzezi Reza R Ivry Richard B RB

Communications biology 20180322

Implicit sensorimotor adaptation is traditionally described as a process of error reduction, whereby a fraction of the error is corrected for with each movement. Here, in our study of healthy human participants, we characterize two constraints on this learning process: the size of adaptive corrections is only related to error size when errors are smaller than 6°, and learning functions converge to a similar level of asymptotic learning over a wide range of error sizes. These findings are problem ...[more]

PMID: 30271906

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