caa a22 4500 467940487 CHVBK 20180406153011.0 cr unu---uuuuu 170328e20060901xx s 000 0 eng 10.1007/s00421-006-0265-y doi (NATIONALLICENCE)springer-10.1007/s00421-006-0265-y Motor cortex excitability changes preceding voluntary muscle activity in simple reaction time task [Elektronische Daten] [M. Nikolova, N. Pondev, L. Christova, W. Wolf, A. Kossev] The effect of transcranial magnetic stimulation (TMS) on reaction time (RT) and motor cortex excitability in the premovement period was investigated. Single and paired-pulse TMS with 3 and 13ms interstimulus intervals (ISI) were applied to the left motor cortex at different delays after a visual command for isometric right hand index finger abduction. Motor evoked potentials (MEPs) recorded from the right first dorsal interosseous (FDI) were analysed to assess cortex excitability. The MEPs in response to single pulse TMS were gradually increased in the premovement period in general, but strongly augmented in a period of 90-100ms before the voluntary myoelectrical activity (EMG) onset. In paired-pulse TMS (13ms ISI), the MEP augmentation was smaller but started earlier before the EMG burst, and a gradual increase of MEP amplitudes was not evident. In case of 3ms ISI, the expected intracortical inhibition (ICI) was evident only when TMS preceded the voluntary EMG by an interval of more than 60ms, but at shorter intervals, rather some MEP augmentation was observed. Generally, the augmentation of MEPs in the premovement period was more pronounced in single pulse TMS. Most strikingly, a dead band period without MEP occurrences was observed within an interval of 30-50ms before the voluntary EMG. In conclusion, parallel action of intracortical facilitation (ICF) and ICI as well as different dynamic behaviour of ICF and pre movement facilitation may explain the earlier mentioned effects. Moreover, this leads to an extended description of the rather subtle TMS influence on RT. Springer-Verlag, 2006 Transcranial magnetic stimulation nationallicence Motor cortex nationallicence Reaction time nationallicence Voluntary movement nationallicence Human nationallicence Nikolova M. Institute of Biophysics, Bulgarian Academy of Sciences, Acad. G. Bontchev Str., Bldg. 21, 1113, Sofia, Bulgaria aut Pondev N. Institute of Biophysics, Bulgarian Academy of Sciences, Acad. G. Bontchev Str., Bldg. 21, 1113, Sofia, Bulgaria aut Christova L. Institute of Biophysics, Bulgarian Academy of Sciences, Acad. G. Bontchev Str., Bldg. 21, 1113, Sofia, Bulgaria aut Wolf W. Department of Electrical Engineering and Information Technology, University AF, Munich, Germany aut Kossev A. Institute of Biophysics, Bulgarian Academy of Sciences, Acad. G. Bontchev Str., Bldg. 21, 1113, Sofia, Bulgaria aut European Journal of Applied Physiology Springer-Verlag 98/2(2006-09-01), 212-219 1439-6319 98:2<212 2006 98 421 https://doi.org/10.1007/s00421-006-0265-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00421-006-0265-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Nikolova M. Institute of Biophysics, Bulgarian Academy of Sciences, Acad. G. Bontchev Str., Bldg. 21, 1113, Sofia, Bulgaria aut NATIONALLICENCE 700 1- Pondev N. Institute of Biophysics, Bulgarian Academy of Sciences, Acad. G. Bontchev Str., Bldg. 21, 1113, Sofia, Bulgaria aut NATIONALLICENCE 700 1- Christova L. Institute of Biophysics, Bulgarian Academy of Sciences, Acad. G. Bontchev Str., Bldg. 21, 1113, Sofia, Bulgaria aut NATIONALLICENCE 700 1- Wolf W. Department of Electrical Engineering and Information Technology, University AF, Munich, Germany aut NATIONALLICENCE 700 1- Kossev A. Institute of Biophysics, Bulgarian Academy of Sciences, Acad. G. Bontchev Str., Bldg. 21, 1113, Sofia, Bulgaria aut NATIONALLICENCE 773 0- European Journal of Applied Physiology Springer-Verlag 98/2(2006-09-01), 212-219 1439-6319 98:2<212 2006 98 421 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer