Repetitive Transcranial Magnetic Stimulation of Contralesional Primary Motor Cortex Improves Hand Function After Stroke

N. Takeuchi, T. Chuma, Y. Matsuo, I. Watanabe, K. Ikoma
2005 Stroke  
and Purpose-A recent report has demonstrated that the contralesional primary motor cortex (M1) inhibited the ipsilesional M1 via an abnormal transcallosal inhibition (TCI) in stroke patients. We studied whether a decreased excitability of the contralesional M1 induced by 1 Hz repetitive transcranial magnetic stimulation (rTMS) caused an improved motor performance of the affected hand in stroke patients by releasing the TCI. Methods-We conducted a double-blind study of real versus sham rTMS in
more » ... rsus sham rTMS in stroke patients. After patients had wellperformed motor training to minimize the possibility of motor training during the motor measurement, they were randomly assigned to receive a subthreshold rTMS at the contralesional M1 (1 Hz, 25 minutes) or sham stimulation. Results-When compared with sham stimulation, rTMS reduced the amplitude of motor-evoked potentials in contralesional M1 and the TCI duration, and rTMS immediately induced an improvement in pinch acceleration of the affected hand, although a plateau in motor performance had been reached by the previous motor training. This improvement in motor function after rTMS was significantly correlated with a reduced TCI duration. Conclusions-We have demonstrated that a disruption of the TCI by the contralesional M1 virtual lesion caused a paradoxical functional facilitation of the affected hand in stroke patients; this suggests a new neurorehabilitative strategy for stroke patients. (Stroke. 2005;36:2681-2686.)
doi:10.1161/01.str.0000189658.51972.34 pmid:16254224 fatcat:4gvjtkki35cdlltosvg4z6b6ti