Investigation of neural substrates related to visuomotor interaction during de novo motor skill learning

Abstract

Although the sensorimotor cortices play a crucial role in motor control and learning, which specific regions are responsible for motor control and learning, and how they interact with each other are less understood, especially in de novo motor learning, or learning a motor skill from scratch. Participants learned arbitrary visuomotor mapping with a continuous visuomotor task in fMRI. Visual feedback of a cursor was altered to dissociate the functions of motor and somatosensory cortices. Hence, they controlled a cursor under two alternating conditions: online cursor feedback is available or unavailable. Double dissociation of fMRI activity in subregions of the sensorimotor and visual cortices and their interaction, mediated by the visual feedback, were found. A significant decrease in functional connectivity between somatosensory cortices and early visual cortices was also found, which was highly correlated with performance improvement. These findings support the distinct interaction between subregions of sensorimotor cortices and visual cortices while highlighting the more dominant role of somatosensory cortices over motor cortices during de novo motor learning.