BACKGROUND 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 stroke patients. After patients had well- performed 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.
RCT Entities:
BACKGROUND 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 strokepatients. 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 strokepatients by releasing the TCI. METHODS: We conducted a double-blind study of real versus sham rTMS in strokepatients. After patients had well- performed 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 strokepatients; this suggests a new neurorehabilitative strategy for strokepatients.
Authors: Laura Bonzano; Andrea Tacchino; Luca Roccatagliata; Giovanni Luigi Mancardi; Giovanni Abbruzzese; Marco Bove Journal: Hum Brain Mapp Date: 2011-02 Impact factor: 5.038
Authors: Christian Grefkes; Dennis A Nowak; Ling E Wang; Manuel Dafotakis; Simon B Eickhoff; Gereon R Fink Journal: Neuroimage Date: 2009-12-18 Impact factor: 6.556