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bioRxiv · 10.1101/189597

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

Kim, H.·Morehead, J. R.·Parvin, D.·Moazzezi, R.·Ivry, R.
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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{degrees}, 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.

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Kim, H., Morehead, J. R., Parvin, D., Moazzezi, R., Ivry, R.. 2017-09-15. Invariant errors reveal limitations in motor correction rather than constraints on error sensitivity. https://doi.org/10.1101/189597

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