Interaction of tactile input in the human primary and secondary somatosensory cortex -: A magnetoencephalographic study
Interaction of tactile input in the human primary and secondary somatosensory cortex -: A magnetoencephalographic study
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DOI：
10.1006/nimg.2001.0855
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发表时间：
2001-09-01
期刊：
影响因子：
5.7
通讯作者：
Scherg, M
中科院分区：
文献类型：
--
作者：
Hoechstetter, K;Rupp, A;Scherg, M
本文用全脑磁图研究了在初级（SI）和次级躯体感觉皮层（SII）两个手指部位同时进行触觉输入的相互作用。以1.6 s的刺激间隔向右手和左手的手指递送短压力脉冲。分别或同时刺激左1指第一节指骨和其他四个部位。我们比较了四个地点与增加的距离：第二节指骨的左手第1，左手第5，第1和第5的右手手指。使用时空源分析计算对侧SI和双侧SII源活动的时间演变。通过比较同时刺激期间的源活动与由单独刺激引起的源活动的总和来评估相互作用。在对侧SI中只观察到同一只手的刺激，随着距离的增加而减少。在SII中，同手和对手的所有手指都与左手第1指有显著的交互作用。当刺激双边，SII源波形非常相似的时间过程中的反应，以单独的刺激的另一只手。因此，在双边同时刺激，对侧输入到达第一次在SII出现抑制后来的同侧输入。同样，单独的响应输入在两个单侧手指网站，稍早到达SII占主导地位的同时响应。我们的研究结果证实了以前的研究结果相当大的重叠在皮质的手表示在SII和说明半球专业化对侧输入时，同时发生的刺激双边。(C)北京：科学出版社.
Interaction of simultaneous tactile input at two finger sites in primary (SI) and secondary somatosensory cortex (SII) was studied by whole-head magnetoencephalography. Short pressure pulses were delivered to fingers of the right and left hand at an interstimulus interval of 1.6 s. The first phalanx of the left digit 1 and four other sites were stimulated either separately or simultaneously. We compared four sites with increasing distance: the second phalanx of left digit 1, left digit 5, and digits 1 and 5 of the right hand. The temporal evolution of source activity in the contralateral SI and bilateral SII was calculated using spatiotemporal source analysis. Interaction was assessed by comparing the source activity during simultaneous stimulation with the sum of the source activities elicited by separate stimulation. Significant suppressive interaction was observed in contralateral SI only for stimuli at the same hand, decreasing with distance. In SII, all digits of the same and the opposite hand interacted significantly with left digit 1. When stimulating bilaterally, SII source waveforms closely resembled the time course of the response to separate stimulation of the opposite hand. Thus, in bilateral simultaneous stimulation, the contralateral input arriving first in SII appeared to inhibit the later ipsilateral input. Similarly, the separate response to input at two unilateral finger sites which arrived slightly earlier in SII dominated the simultaneous response. Our results confirm previous findings of considerable overlap in the cortical hand representation in SII and illustrate hemispheric specialization to contralateral input when simultaneous stimuli occur bilaterally. (C) 2001 Academic Press.