Enhanced human sensorimotor integration via self-modulation of the somatosensory activity

Kinesthetic motor imagery, the mental rehearsal of movement and its associated sensations1,2, activates somatosensory and motor cortices3,4. Motor imagery improves performance in neurorehabilitation5, sports6, and instrument play7. However, the mechanism that enhances performance through repetitive motor imagery remains unclear. Here, we combined individually tailored motor imagery training combined with closed-loop neurofeedback training, neurophysiology, and behavioral assessment to characterize how the training can modulate the somatosensory system and improve performance. The closed-loop training using real-time feedback of human electroencephalogram (EEG) signals enhanced participants self-modulation ability of intrinsic neural oscillations in the primary somatosensory cortex (S1) within 30 minutes. Further, the short-term reorganization in S1 was corroborated by the post-training reactivity enhancement revealed by changes in somatosensory evoked potential (SEP) amplitude of early component originating from S18. Meanwhile those derived from peripheral sensory fibers were maintained, suggesting that the closed-loop training manipulated cortical activities. Behavioral evaluation demonstrated improved performance during keyboard touch-typing indexed by resolved the speed-accuracy trade-off9. Collectively, our results provide evidence that mentally rehearsed movement during kinesthetic motor imagery induces functional reorganization of S1 activities that can contribute to performance improvement.