The first 2 authors (M.G. and J.T.) contributed equally to this study.
Effect of different approaches to target force on transcranial magnetic stimulation responses
Article first published online: 15 JUL 2013
Copyright © 2013 Wiley Periodicals, Inc.
Muscle & Nerve
Volume 48, Issue 3, pages 430–432, September 2013
How to Cite
Gruet, M., Temesi, J., Rupp, T., Millet, G. Y. and Verges, S. (2013), Effect of different approaches to target force on transcranial magnetic stimulation responses. Muscle Nerve, 48: 430–432. doi: 10.1002/mus.23786
This study was supported by a grant for research on the brain during exercise from the Fonds de Dotation Recherche en Santé Respiratoire, appel d'offres 2011 (to M.G.) and a doctoral research grant from the Rhône-Alpes Region (to J.T.).
- Issue published online: 27 AUG 2013
- Article first published online: 15 JUL 2013
- Accepted manuscript online: 30 JAN 2013 10:40PM EST
- Manuscript Accepted: 8 JAN 2013
- motor-evoked potential;
- muscle contraction;
- silent period;
- transcranial magnetic stimulation
Introduction: The aim of this study was to determine whether the manner in which a target force is approached can influence the electromyographic (EMG) and mechanical parameters evoked by transcranial magnetic stimulation (TMS) during brief muscle contractions. Methods: The amplitude of motor-evoked potentials (MEP) and superimposed twitch and the duration of the silent period were recorded in 8 healthy participants in response to TMS delivered during brief isometric voluntary contractions of the quadriceps maintaining a target force (10% and 50% of maximal voluntary force) or gradually increasing or decreasing to reach this point. Results: MEP and superimposed twitch, unlike the silent period, are influenced by the manner of reaching a low force. Conclusions: Clear instructions must be provided to research participants and patients. Rapidly increasing to a target force without exceeding it and maintaining the force before the delivery of TMS results in stable, representative MEP amplitudes. Muscle Nerve 48: 430–432, 2013