Adaptive Regulation of Motor Variability.


Dhawale AK, Miyamoto YR, Smith MA, Ölveczky BP. Adaptive Regulation of Motor Variability. Current Biology [Internet]. 2019;pii: S0960-9822 (19) :31102-9.


Trial-to-trial movement variability can both drive motor learning and interfere with expert performance, suggesting benefits of regulating it in context-specific ways. Here we address whether and how the brain regulates motor variability as a function of performance by training rats to execute ballistic forelimb movements for reward. Behavioral datasets comprising millions of trials revealed that motor variability is regulated by two distinct processes. A fast process modulates variability as a function of recent trial outcomes, increasing it when performance is poor and vice versa. A slower process tunes the gain of the fast process based on the uncertainty in the task's reward landscape. Simulations demonstrated that this regulation strategy optimizes reward accumulation over a wide range of time horizons, while also promoting learning. Our results uncover a sophisticated algorithm implemented by the brain to adaptively regulate motor variability to improve task performance. VIDEO ABSTRACT.


PMID:31630947  DOI:10.1016/j.cub.2019.08.052

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Last updated on 12/16/2019