Reliability of Motor Evoked Potentials Induced by Transcranial Magnetic Stimulation: The Effects of Initial Motor Evoked Potentials Removal

Introduction: Transcranial magnetic stimulation (TMS) is a useful tool for assessment of corticospinal excitability (CSE) changes in both healthy individuals and patients with brain disorders. The usefulness of TMS-elicited motor evoked potentials (MEPs) for the assessment of CSE in a clinical conte...

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Main Authors: Fahimeh Hashemirad, Maryam Zoghi, Paul B Fitzgerald, Shapour Jaberzadeh
Format: Article
Language:English
Published: Iran University of Medical Sciences 2017-01-01
Series:Basic and Clinical Neuroscience
Subjects:
Online Access:http://bcn.iums.ac.ir/browse.php?a_code=A-10-847-1&slc_lang=en&sid=1
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author Fahimeh Hashemirad
Maryam Zoghi
Paul B Fitzgerald
Shapour Jaberzadeh
author_facet Fahimeh Hashemirad
Maryam Zoghi
Paul B Fitzgerald
Shapour Jaberzadeh
author_sort Fahimeh Hashemirad
collection DOAJ
description Introduction: Transcranial magnetic stimulation (TMS) is a useful tool for assessment of corticospinal excitability (CSE) changes in both healthy individuals and patients with brain disorders. The usefulness of TMS-elicited motor evoked potentials (MEPs) for the assessment of CSE in a clinical context depends on their intra-and inter-session reliability. This study aimed to evaluate if removal of initial MEPs elicited by using two types of TMS techniques influences the reliability scores and whether this effect is different in blocks with variable number of MEPs. Methods: Twenty-three healthy participants were recruited in this study. The stimulus intensity was set at 120% of resting motor threshold (RMT) for one group while the stimulus intensity was adjusted to record MEPs up to 1 mV for the other group. Twenty MEPs were recorded at 3 time points on 2 separate days. An intra-class correlation coefficient (ICC) reliability with absolute agreement and analysis of variance model were used to assess reliability of the MEP amplitudes for blocks with variable number of MEPs. Results: A decrease in ICC values was observed with removal of 3 or 5 MEPs in both techniques when compared to all MEP responses in any given block. Therefore, removal of the first 3 or 5 MEPs failed to further increase the reliability of MEP responses. Conclusion: Our findings revealed that a greater number of trials involving averaged MEPs can influence TMS reliability more than removal of the first trials.
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spelling doaj.art-8c6afc2286134b36903e157d4864c34f2024-03-02T19:16:39ZengIran University of Medical SciencesBasic and Clinical Neuroscience2008-126X2228-74422017-01-01814350Reliability of Motor Evoked Potentials Induced by Transcranial Magnetic Stimulation: The Effects of Initial Motor Evoked Potentials RemovalFahimeh Hashemirad0Maryam Zoghi1Paul B Fitzgerald2Shapour Jaberzadeh3 Department of Physiotherapy, School of Primary Health Care, Medicine, Nursing and Health Sciences, Monash University, Melbourne, Australia. Department of Medicine at Royal Melbourne Hospital, University of Melbourne, Melbourne, Australia. Monash Alfred Psychiatry Research Centre, Alfred and Monash University Central Clinical School, Melbourne, Australia. Department of Physiotherapy, School of Primary Health Care, Medicine, Nursing and Health Sciences, Monash University, Melbourne, Australia. Introduction: Transcranial magnetic stimulation (TMS) is a useful tool for assessment of corticospinal excitability (CSE) changes in both healthy individuals and patients with brain disorders. The usefulness of TMS-elicited motor evoked potentials (MEPs) for the assessment of CSE in a clinical context depends on their intra-and inter-session reliability. This study aimed to evaluate if removal of initial MEPs elicited by using two types of TMS techniques influences the reliability scores and whether this effect is different in blocks with variable number of MEPs. Methods: Twenty-three healthy participants were recruited in this study. The stimulus intensity was set at 120% of resting motor threshold (RMT) for one group while the stimulus intensity was adjusted to record MEPs up to 1 mV for the other group. Twenty MEPs were recorded at 3 time points on 2 separate days. An intra-class correlation coefficient (ICC) reliability with absolute agreement and analysis of variance model were used to assess reliability of the MEP amplitudes for blocks with variable number of MEPs. Results: A decrease in ICC values was observed with removal of 3 or 5 MEPs in both techniques when compared to all MEP responses in any given block. Therefore, removal of the first 3 or 5 MEPs failed to further increase the reliability of MEP responses. Conclusion: Our findings revealed that a greater number of trials involving averaged MEPs can influence TMS reliability more than removal of the first trials.http://bcn.iums.ac.ir/browse.php?a_code=A-10-847-1&slc_lang=en&sid=1Transcranial magnetic stimulation Reliability Evoked response variability First dorsal interosseous muscles
spellingShingle Fahimeh Hashemirad
Maryam Zoghi
Paul B Fitzgerald
Shapour Jaberzadeh
Reliability of Motor Evoked Potentials Induced by Transcranial Magnetic Stimulation: The Effects of Initial Motor Evoked Potentials Removal
Basic and Clinical Neuroscience
Transcranial magnetic stimulation
Reliability
Evoked response variability
First dorsal interosseous muscles
title Reliability of Motor Evoked Potentials Induced by Transcranial Magnetic Stimulation: The Effects of Initial Motor Evoked Potentials Removal
title_full Reliability of Motor Evoked Potentials Induced by Transcranial Magnetic Stimulation: The Effects of Initial Motor Evoked Potentials Removal
title_fullStr Reliability of Motor Evoked Potentials Induced by Transcranial Magnetic Stimulation: The Effects of Initial Motor Evoked Potentials Removal
title_full_unstemmed Reliability of Motor Evoked Potentials Induced by Transcranial Magnetic Stimulation: The Effects of Initial Motor Evoked Potentials Removal
title_short Reliability of Motor Evoked Potentials Induced by Transcranial Magnetic Stimulation: The Effects of Initial Motor Evoked Potentials Removal
title_sort reliability of motor evoked potentials induced by transcranial magnetic stimulation the effects of initial motor evoked potentials removal
topic Transcranial magnetic stimulation
Reliability
Evoked response variability
First dorsal interosseous muscles
url http://bcn.iums.ac.ir/browse.php?a_code=A-10-847-1&slc_lang=en&sid=1
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