Centrifugal regulation of human cortical responses to a task-relevant somatosensory signal triggering voluntary movement
Centrifugal regulation of human cortical responses to a task-relevant somatosensory signal triggering voluntary movement
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DOI：
10.1016/j.neuroimage.2006.05.015
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发表时间：
2006-09-01
期刊：
影响因子：
5.7
通讯作者：
Kakigi, Ryusuke
中科院分区：
文献类型：
--
作者：
Kida, Tetsuo;Wasaka, Toshiaki;Kakigi, Ryusuke
许多研究报道了灵长类动物初级和次级躯体感觉皮层(SI和SIT)对任务无关刺激的反应与运动相关的调制。在本研究中，脑磁图(MEG)被用来检测人类SI和SIT对触发自主运动的任务相关的体感信号的神经反应的自上而下的离心式调节。九名健康的成年人参与了这项研究。在视觉警告信号之后，2 S随后将躯体感觉命令信号传递到手腕的右侧正中神经。三种警告信号告知参与者在呈现命令信号时应执行的反应(休息或伸展右手食指，伸展左手食指)。体感刺激既被用来产生神经反应，也被用来触发随意运动，因此被认为是与任务相关的信号。这些反应是使用全头脑磁图系统记录的。与对照条件相比，当信号触发自主运动时，SI周围的P35m反应的幅度降低，而初级SI反应N20m没有改变，而在70-100ms达到峰值的双侧SII反应增强，峰潜伏期缩短。在每个受试者中，SI和SIT反应的峰值潜伏期早于最早的自主肌肉激活开始。随后，随着运动的进行，双侧的坐骨神经反应也增强了。综上所述，由任务相关体感信号诱发的SI和SIT中的神经活动在传入输入之前受到运动相关神经活动的不同调节。目前的发现表明，SI和SIT在躯体感觉-运动调节中的功能存在差异。(C)2006 Elsevier Inc.保留所有权利。
Many studies have reported a movement-related modulation of response in the primary and secondary somatosensory cortices (SI and Sit) to a task-irrelevant stimulation in primates. In the present study, magnetoencephalography (MEG) was used to examine the top-down centrifugal regulation of neural responses in the human SI and Sit to a task-relevant somatosensory signal triggering a voluntary movement. Nine healthy adults participated in the study. A visual warning signal was followed 2 s later by a somatosensory imperative signal delivered to the right median nerve at the wrist. Three kinds of warning signal informed the participants of the reaction which should be executed on presentation of the imperative signal (rest or extension of the right index finger, extension of the left index ringer). The somatosensory stimulation was used to both generate neural responses and trigger voluntary movement and therefore was regarded as a task-relevant signal. The responses were recorded using a whole-head MEG system. The P35m response around the SI was reduced in magnitude without alteration of the primary SI response, N20m, when the signal triggered a voluntary movement compared to the control condition, whereas bilateral SII responses peaking at 70-100 ms were enhanced and the peak latency was shortened. The peak latency of the responses in the SI and Sit preceded the onset of the earliest voluntary muscle activation in each subject. Later bilateral perisylvian responses were also enhanced with movement. In conclusion, neural activities in the SI and Sit evoked by task-relevant somatosensory signals are regulated differently by motor-related neural activities before the afferent inputs. The present findings indicate a difference in function between the SI and Sit in somatosensory-motor regulation. (c) 2006 Elsevier Inc. All rights reserved.