Increased excitability and reduced intracortical inhibition in the ipsilateral primary motor cortex during a fine-motor manipulation task
Increased excitability and reduced intracortical inhibition in the ipsilateral primary motor cortex during a fine-motor manipulation task
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DOI：
10.1016/j.brainres.2010.11.049
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发表时间：
2011-01-31
期刊：
影响因子：
2.9
通讯作者：
Funase, Kozo
中科院分区：
文献类型：
--
作者：
Morishita, Takuya;Ninomiya, Masato;Funase, Kozo
在10名右撇子受试者中，研究了感觉运动任务对经胼胝体通路介导的同侧初级运动皮层（ipsi-M1）兴奋性的影响，包括短间隔皮质内抑制（SIC!）和皮质内促进（ICF）的变化。经颅磁刺激（TMS）可引起第一背骨间（FDI）的运动诱发电位（MEP）。测试- tms强度调整到静息运动阈值（rMT）的120%左右。配对脉冲TMS模式中，调节-TMS强度设定为rMT的80%，SICI和ICF的刺激间隔分别为3 ms和12 ms。作为感觉运动任务，采用精细运动操作任务（用筷子夹起、搬运和释放玻璃球）。此外，伪调频（pFM）任务也作为控制任务。这些任务是分别用两只手完成的。与pFM任务相比，FM任务中诱发的mep显著增加，且这种效应不依赖于执行这些任务的FDI的肌电活动。在调频任务中，SICI显著降低，表明ipsi-M1抑制解除，当受试者使用非优势手时也注意到这些影响。本研究结果表明，FM和pFM任务对ipsi-M1兴奋性的影响差异是由它们的性质引起的。(C) 2010 Elsevier B.V.版权所有
The effects of a sensorimotor task on ipsilateral primary motor cortex (ipsi-M1) excitability mediated via the transcallosal pathway, including the changes in short-interval intracortical inhibition (SIC!) and intracortical facilitation (ICF), were examined in ten right-handed subjects. Transcranial magnetic stimulation (TMS) was delivered to evoke a motor evoked potential (MEP) from the first dorsal interosseous (FDI). The test-TMS intensity was adjusted to around 120% of the resting motor threshold (rMT). For the paired-pulse TMS paradigm, the conditioning-TMS intensity was set to 80% of the rMT, and the interstimulus interval was fixed at 3 ms for SICI and 12 ms for ICF. As a sensorimotor task, a fine-motor manipulation (FM) task (using chopsticks to pick up, transport, and release glass balls) was adopted. In addition, a pseudo-FM (pFM) task was also performed as a control task. These tasks were carried out using each hand separately. The MEPs evoked during the FM task were markedly increased compared with those evoked during the pFM task, and these effects were not dependent on the electromyographic activity of the FDI performing these tasks. SICI was significantly decreased during the FM task, indicating disinhibition of the ipsi-M1, and these effects were also noted when the subjects used their non-dominant hand. The present findings suggest that the differences between the effects of the FM and pFM tasks on ipsi-M1 excitability were caused by their property. (C) 2010 Elsevier B.V. All rights reserved.