Inhibition of the unaffected motor cortex by 1 Hz repetitive transcranial magnetic stimulation enhances motor performance and training effect of the paretic hand in patients with chronic stroke

Objective: Recent reports demonstrated that low-frequency repetitive transcranial magnetic stimulation (rTMS) over the unaffected hemisphere improved the affected hand function in chronic stroke patients. We investigated whether 1 Hz rTMS improved the motor learning of the affected hand in patients after stroke. Design: A double-blind study. Patients: Twenty patients with chronic subcortical stroke. Methods: The patients were randomly assigned to receive either a sub-threshold rTMS over the unaffected hemisphere (1 Hz, 25 minutes) or sham stimulation, and all patients performed a pinching task after stimulation. We evaluated the motor function of the affected hand and the excitatory and inhibitory function of the affected motor cortex by transcranial magnetic stimulation. Results: Compared with sham stimulation, rTMS induced an increase in the excitability of the affected motor cortex (p<0.001) and an improvement in acceleration of the affected hand (p=0.006). Moreover, the effect of motor training on pinch force was enhanced by rTMS (p<0.001). These improvement in the motor function lasted for one week after rTMS and motor training (p < 0.001). Conclusion: rTMS improved the motor learning of the affected hand in patients after stroke; thus, it can apply as a new rehabilitation strategy for patients after stroke.