Quantification of motoneurone pool responses to transcranial magnetic stimulation with surface electromygraphy

• Autorzy: Awiszus F.
• Języki publikacji: EN

Abstrakty

EN

Transcranial magnetic stimulation (TMS) is a noninvasive technique to investigate human motoneurone pools (spinal and cortical). Despite the fact that the number of publications dealing with TMS is growing rapidly, there is currently no clear standard how TMS responses should be quantified. Many current studies cite the guidelines that were published in 1994. These guidelines, however, mention (more or less implicitly) at least three ways to quantify the motor evoked potential (MEP) amplitude for a given stimulus strength. In order to clarify to what an extent these different quantification concepts provide different results, MEP measurements were performed on 12 hand muscles of 4 normal volunteers. The input/output curve derived from the threshold concept of the guidelines was found to differ significantly from the most popular concepts of input/ output curve quantification (averaged MEP amplitudes or amplitudes of averaged MEPs). On the other hand, using the median of MEP amplitudes provided an output measure that was consistent with the input/output curve derived from the threshold concept. These results indicate, that the differences in the output quantification concepts need to be taken into account when interpreting results of MEP measurements. In particular, using consistent concepts like threshold and median MEP amplitude should alleviate the problem of interpreting changes observed in MEP parameters obtained by TMS.

Słowa kluczowe

EN

transcranial magnetic stimulation; response quantification; methodology; motor evoked potential amplitude

PL

przezczaszkowa stymulacja magnetyczna; kwantyfikacja odpowiedzi; potencjał wywołany

• Wydawca: Nałęcz Institute of Biocybernetics and Biomedical Engineering of the Polish Academy of Sciences ; Elsevier
• Czasopismo: Biocybernetics and Biomedical Engineering
• Rocznik: 2005
• Tom: Vol. 25, no. 3
• Strony: 3--10
• Opis fizyczny: Bibliogr. 16 poz., rys.

Twórcy

autor

Awiszus F.

• Neuromuscular Research Group at the Department of Orthopedics, Otto-von-Guericke University, Magdeburg, Germany,

Bibliografia

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