TY - JOUR
T1 - Interhemispheric asymmetry of corticomotor excitability after chronic cerebellar infarcts
AU - Farias Da Guarda, Suzete Nascimento
AU - Cohen, Leonardo G.
AU - Da Cunha Pinho, Marco
AU - Yamamoto, Fábio Iuji
AU - Marchiori, Paulo Eurípedes
AU - Scaff, Milberto
AU - Conforto, Adriana Bastos
N1 - Funding Information:
Acknowledgments Dr. Suzete N. Farias received a research scholarship from Fundação Faculdade de Medicina, Clinics Hospital/São Paulo University. We thank Michael Dimyan for helpful comments and suggestions.
PY - 2010/9
Y1 - 2010/9
N2 - Early after stroke, there is loss of intracortical facilitation (ICF) and increase in short-interval intracortical inhibition (SICI) in the primary motor cortex (M1) contralateral to a cerebellar infarct. Our goal was to investigate intracortical M1 function in the chronic stage following cerebellar infarcts (>4 months). We measured resting motor threshold (rMT), SICI, ICF, and ratios between motor-evoked potential amplitudes (MEP) and supramaximal M response amplitudes (MEP/M; %), after transcranial magnetic stimulation was applied to the M1 contralateral (M1contralesional) and ipsilateral (M1 ipsilesional) to the cerebellar infarct in patients and to both M1s of healthy age-matched volunteers. SICI was decreased in M1 contralesional compared to M1ipsilesional in the patient group in the absence of side-to-side differences in controls. There were no significant interhemispheric or between-group differences in rMT, ICF, or MEP/M (%). Our results document disinhibition of M1contralesional in the chronic phase after cerebellar stroke.
AB - Early after stroke, there is loss of intracortical facilitation (ICF) and increase in short-interval intracortical inhibition (SICI) in the primary motor cortex (M1) contralateral to a cerebellar infarct. Our goal was to investigate intracortical M1 function in the chronic stage following cerebellar infarcts (>4 months). We measured resting motor threshold (rMT), SICI, ICF, and ratios between motor-evoked potential amplitudes (MEP) and supramaximal M response amplitudes (MEP/M; %), after transcranial magnetic stimulation was applied to the M1 contralateral (M1contralesional) and ipsilateral (M1 ipsilesional) to the cerebellar infarct in patients and to both M1s of healthy age-matched volunteers. SICI was decreased in M1 contralesional compared to M1ipsilesional in the patient group in the absence of side-to-side differences in controls. There were no significant interhemispheric or between-group differences in rMT, ICF, or MEP/M (%). Our results document disinhibition of M1contralesional in the chronic phase after cerebellar stroke.
KW - Cerebellar disease
KW - Paired pulse
KW - Stroke
KW - Transcranial magnetic stimulation
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U2 - 10.1007/s12311-010-0176-7
DO - 10.1007/s12311-010-0176-7
M3 - Article
C2 - 20461489
AN - SCOPUS:78049231341
SN - 1473-4222
VL - 9
SP - 398
EP - 404
JO - Cerebellum
JF - Cerebellum
IS - 3
ER -