Effect of Task Error on Implicit Motor Adaptation

Abstract

Motor adaptation is essential for maintaining coordination in daily activities. Implicit motor adaptation, operating unconsciously, is primarily considered to be driven by sensory prediction errors. This study aims to investigate how another error signal, task error, affects implicit adaptation across varying perturbation sizes using a visuomotor reaching paradigm. Employing a Single Trial Learning (STL) approach, we compare initial adaptation responses to different target types: a small dot target reinforcing strict spatial accuracy, and a large arc target permitting greater movement endpoint variability. By manipulating target size, we systematically alter task error presence or absence, isolating its influence on implicit motor adaptation, while holding sensory prediction error constant. These findings will advance our understanding of task error and sensory prediction error interactions in the early stages of implicit motor learning. Ultimately, this work aims to refine current motor learning models and inform targeted error type utilization in rehabilitation and training strategies.