Exploring Brain Inhibition and Facilitation by Transcranial Magnetic Stimulation: Is there a role of repetitive spinal motor neuron discharges (repMND) in the conventional paired-pulsed paradigm of short intra-cortical inhibition (SICI) and intra-cortical facilitation (ICF)?

Details

Ressource 1Download: Mémoire no 3283 M. Miaz.pdf (1054.07 [Ko])
State: Public
Version: After imprimatur
Serval ID
serval:BIB_70E01D12A20E
Type
A Master's thesis.
Publication sub-type
Master (thesis) (master)
Collection
Publications
Institution
Title
Exploring Brain Inhibition and Facilitation by Transcranial Magnetic Stimulation: Is there a role of repetitive spinal motor neuron discharges (repMND) in the conventional paired-pulsed paradigm of short intra-cortical inhibition (SICI) and intra-cortical facilitation (ICF)?
Author(s)
MIAZ B.
Director(s)
BENNINGER D.
Institution details
Université de Lausanne, Faculté de biologie et médecine
Publication state
Accepted
Issued date
2016
Language
english
Number of pages
28
Abstract
Objective: To study the role of spinal repMND in the paired-pulsed (PP) paradigms of SICI and ICF by combining PP with TMS, TST, QuadS and QuintS techniques and to explore their variability.
Background: Transcranial magnetic stimulation (TMS) leads to repetitive spinal motor neuron discharges (repMNDs). The paired-pulse TMS (PP-TMS) paradigm allows the exploration of the motor cortex physiology. The triple stimulation technique (TST) and an extended TST-technique including a 4th and 5th stimulation, Quadruple (QuadS) and Quintuple (QuintS) stimulation, respectively, allow a more precise exploration of the central motor conduction and of repMND.
Design/Methods: We explored the PP TMS paradigms of short intracortical inhibition (SICI) with an inter-stimulus interval (ISI) of 2ms and intracortical facilitation (ICF) with an ISI of 10ms in the conventional way (TMS), combined with the TST, and with the QuadS and QuintS in a randomized design in 20 healthy volunteers
Results: About half of the subjects have repMND following a single pulse TMS in the QuadS and QuintS condition (60% and 40%, respectively) and generally more in the QuadS than in the QuintS condition. In both the QuadS and the QuintS, there appear more repMND in the PP-TMS paradigm of ICF than with a single pulse TMS and less than latter in SICI. The variability differs considerably between subjects, but combining the PP paradigms with the TST reduced variability of SICI by -27% but not for ICF or SP. There were subjects showing inhibition and facilitation when the opposite was expected.
Conclusions: These results suggest that there is a contribution of repMND in the conditioned responses of PP-TMS. The large variability precludes their utility in clinical practice. This needs to be further explored.

Keywords
TMS, TST, PP-paradigms, MEP, repMND, cortico-spinal excitability
Create date
05/09/2017 13:38
Last modification date
20/08/2019 14:29
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