Reorganization of Undirected and Directed Cortico-Muscular Connectivity After Exoneuromusculoskeleton-Assisted Telerehabilitation

The effect of motor-level neuromuscular electrical stimulation synchronized with dynamic robot-assisted movement, combined with multimodal feedback on cortico-muscular interaction remains only partially understood. This study aimed to investigate undirected and directed cortico-muscular coherence (CMC and dCMC) altered by a telerehabilitation program assisted by a developed exoneuromusculoskeleton (ENMS) in individuals after stroke. Electroencephalography from the sensorimotor area and electromyography from five lower limb muscles were concurrently measured during isometric ankle dorsiflexion (DF) before and after the program. After the training, a decrease in CMC value was observed in the biceps femoris (BF) muscle, while an increase in CMC value was observed in the vastus medialis oblique (VMO) muscle; ascending dCMC values increased in the tibialis anterior (TA) muscle at both 20% and 40% DF. These findings suggested that the ENMS-assisted training program could modulate the interaction between the cortex and VMO and BF muscles and enhance the TA muscle's ascending pathway.