Generalization in learning of virtual upper limb movements is influenced by motor exploration.

The acquisition of new motor skills from scratch, also known as learning, is an essential aspect of motor development. In learning, the ability to generalize skills acquired under one condition to others is crucial because of the inherently limited range of motor experiences available for learning. However, the presence of generalization in learning and its influencing factors remain unclear. This study aimed to elucidate the generalization of motor learning by examining the motor exploration process, which is the accumulation of motor experiences. To this end, we manipulated the exploration process during practice by changing the target shape using either a small circular target or a bar-shaped target. Our findings demonstrated that the amount of learning during practice was generalized across different conditions. Furthermore, the extent of generalization is influenced by movement variability in the control space, which is irrelevant to the task, rather than the target shapes themselves. These results confirmed the occurrence of generalization in learning and suggest that the exploration process within the control space plays a significant role in facilitating this generalization.