Motor Learning and Transfer Are Symmetric Across Hands

Functional asymmetry between the cerebral hemispheres is a defining feature of the sensorimotor system, with the dominant hemisphere playing a central role in motor control. Whether motor learning is similarly lateralized, however, remains unresolved. To tackle this question, we combined a comprehensive meta-analysis (114 datasets) with a series of well-powered, preregistered experiments (N = 526) to test two core behavioral predictions of hemispheric lateralization in sensorimotor adaptation, a canonical form of motor learning: (1) adaptation is preferentially expressed in the dominant hand and (2) transfers asymmetrically between limbs. Across both approaches, we found that adaptation and interlimb transfer were strikingly symmetric. Together, these findings support a fundamental dissociation in the neural organization of skilled behavior: whereas motor control is lateralized to the dominant hemisphere, motor learning is supported by a neural architecture that functions symmetrically.