Impact of the number of conditioning pulses on motor cortex excitability: a transcranial magnetic stimulation study.
Exp Brain Res
; 239(2): 583-589, 2021 Feb.
Article
em En
| MEDLINE
| ID: mdl-33373012
ABSTRACT
Conditioning transcranial magnetic stimulation (TMS) with subthreshold conditioning stimulus followed by supra-threshold test stimulus at inter-stimulus intervals (ISI) of 1-5 ms results in inhibition (SICI), while ISI at 10-15 ms results in facilitation (ICF). One concerning issue, applying ICF/SICI protocols on patients is the substantial protocol variability. Here, we hypothesized that increasing the number of CS could result in more robust ICF/SICI protocols. Twenty healthy subjects participated in the study. Motor-evoked potentials (MEP) were obtained from conditioning TMS with a varying number of conditioning stimuli in 3, 4, 10, and 15 ms ISI over the primary motor cortex. MEP amplitudes were then compared to examine excitability. TMS with 3, 5, and 7 conditioning stimuli but not with one conditioning stimulus induced ICF. Moreover, 10 ms ISI produced stronger ICF than 15 ms ISI. Significant SICI was only induced with one conditioning stimulus. Besides, 3 ms ISI resulted in stronger SICI than 4 ms ISI. Only a train of conditioning stimuli induced stable ICF and may be more advantageous than the classical paired pulse ICF paradigm.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Transtornos Mentais
/
Córtex Motor
Tipo de estudo:
Diagnostic_studies
Limite:
Humans
Idioma:
En
Revista:
Exp Brain Res
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Alemanha