Target configuration determines how and what we learn during sensorimotor adaptation

Motor adaptation is essential for keeping our actions well-calibrated. However, the role of training context-specifically, the configuration of targets-in shaping motor adaptation remains poorly understood. We tested this by exposing participants to a visuomotor gain perturbation under two contexts: The Extent Group, which trained with targets at two amplitudes in a fixed angular direction, and the Angular Group, which trained with targets at equal amplitude in two angular directions. Strikingly, the groups differed in how they learned: the Angular Group relied predominantly on implicit adaptation, whereas the Extent Group relied more on explicit strategies. Additionally, the two groups differed in what they learned: the Angular Group acquired a translation rule, whereas the Extent Group captured the true gain rule. These findings underscore that training context determines both the processes engaged and the representations formed, underscoring its importance in shaping both how and what we learn.