Handedness and Asymmetry of Motor Skill Learning in Right-handers

BACKGROUND AND PURPOSE: The most remarkable behavioral asymmetry is handedness. The preferred hand often has better performance, motor strength, nonpreferred hand. However, whether these components are associated with skill learning is not clear. METHODS: We evaluated healthy right-handers by setting a series of motor-performance tasks including skill learning, grip strength, and speed. RESULTS: The preferred hand showed better skill performance and learning rate. However, the degree of the right-left difference in grip strength or speed difference did not correlate with the asymmetry in skill-learning rate. Therefore, although the preferred hand exhibits a better skill-learning capacity than the nonpreferred hand, asymmetry in skill learning cannot be explained by motor strength or speed. CONCLUSIONS: Our findings suggest that better skill performance of the right hand in right-handers cannot be attributed to the degree of hand preference score, strength, or motor speed.