Effects of Mapping Uncertainty on Visuomotor Adaptation to Trial-By-Trial Perturbations with Proportional Myoelectric Control

Myoelectric control based on classification of distinct gestures discretizes the output space available to the user, which can make it difficult to react appropriately to novel scenarios such as changing limb position. While proportional myoelectric control is noisy in comparison to pattern recognition control, this noise may be an important component of skill acquisition. Here we implemented a two-dimensional proportional myoelectric controller to investigate the effects of movement direction and mapping uncertainty on adaptation to trial-by-trial perturbations. We found that subjects who practiced hitting targets despite trial-by-trial random modifications of the control mapping adapted to perturbations faster than a control group with low mapping variability. Our findings suggest that exposure to a variable mapping encourages exploratory behavior and underlies a change in adaption rate, which could potentially be used to train myoelectric control users to achieve more robust control.