Kothari Mohit, Svensson Peter, Nielsen Jørgen Feldbæk, Baad-Hansen Lene
Section of Clinical Oral Physiology, Department of Dentistry, Aarhus University, Aarhus C, Denmark; Hammel Neurorehabilitation and Research Centre, Research Unit, Hammel, Denmark.
Section of Clinical Oral Physiology, Department of Dentistry, Aarhus University, Aarhus C, Denmark; MINDLab, Center for Functionally Integrative Neuroscience, Aarhus University Hospital, Aarhus C, Denmark.
Brain Res. 2014 Apr 4;1557:83-9. doi: 10.1016/j.brainres.2014.02.017. Epub 2014 Feb 15.
Paired-pulse transcranial magnetic stimulation (ppTMS) can be used to assess short-interval intracortical inhibitory (SICI) and facilitatory (ICF) networks. Many methodological parameters may however influence the outcome. The aim of the study was to examine the influence of body positions (recline and supine), inter-stimulus intervals (ISI) between the test stimulus (TS) and conditioning stimulus (CS) and intensities of the TS and CS on the degree of SICI and ICF. In studies 1 and 2, fourteen and seventeen healthy volunteers participated respectively. ppTMS was applied over the "hot-spot" of the tongue motor cortex and motor evoked potentials (MEPs) were recorded from contralateral tongue muscles. In study 1, single pulse and three ppTMS ISIs, 2, 10, and 15ms, were applied 8 times each in three blocks (TS: 120%, 140% and 160% of resting motor threshold (rMT); CS: 80% of rMT) in two different body positions (recline and supine) randomly. In study 2, single pulse and four ppTMS ISIs, 2, 2.5, 3, and 3.5ms, were applied 8 times each in randomized order in two blocks (CS: 70% and 80% of rMT; TS: 120% of rMT). There was a significant effect of body position (P=0.049), TS intensities (P<0.001) and ISIs (P<0.001) and interaction between intensity and ISIs (P=0.042) in study 1. In study 2, there was a significant effect of ISI (P<0.001) but not CS intensity (P=0.984) on MEP amplitude. These results may be applied in future studies on the mechanisms of cortical plasticity in the tongue motor pathways using ppTMS and SICI and ICF.
配对脉冲经颅磁刺激（ppTMS）可用于评估短间隔皮质内抑制（SICI）和易化（ICF）网络。然而，许多方法学参数可能会影响结果。本研究的目的是探讨身体姿势（斜躺和仰卧）、测试刺激（TS）与条件刺激（CS）之间的刺激间隔（ISI）以及TS和CS的强度对SICI和ICF程度的影响。在研究1和研究2中，分别有14名和17名健康志愿者参与。ppTMS施加于舌运动皮质的“热点”，并从对侧舌肌记录运动诱发电位（MEP）。在研究1中，单脉冲和三种ppTMS的ISI（2、10和15毫秒）在两个不同身体姿势（斜躺和仰卧）下，以随机顺序在三个组块中各施加8次（TS：静息运动阈值（rMT）的120%、140%和160%；CS：rMT的80%）。在研究2中，单脉冲和四种ppTMS的ISI（2、2.5、3和3.5毫秒）在两个组块中以随机顺序各施加8次（CS：rMT的70%和80%；TS：rMT的120%）。在研究1中，身体姿势（P = 0.049）、TS强度（P < 0.001）和ISI（P < 0.001）以及强度与ISI之间的交互作用（P = 0.042）均有显著影响。在研究2中，ISI对MEP波幅有显著影响（P < 0.001），但CS强度无显著影响（P = 0.984）。这些结果可能应用于未来使用ppTMS以及SICI和ICF对舌运动通路皮质可塑性机制的研究。
