Ipsilateral representation of oral structures in human anterior parietal somatosensory cortex and integration of inputs across the midline
Ipsilateral representation of oral structures in human anterior parietal somatosensory cortex and integration of inputs across the midline
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DOI：
10.1002/cne.10935
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发表时间：
2003-12-22
影响因子：
2.5
通讯作者：
Roberts, TPL
中科院分区：
文献类型：
--
作者：
Disbrow, EA;Hinkley, LBN;Roberts, TPL
顶叶前体感区域3a、3b、1和2通常含有对侧躯体上具有感受野的细胞。然而，来自中线结构(如嘴部)的输入必须跨中线唯一地整合。非人灵长类动物对这些区域的研究支持了这一假设，这些研究证明了口腔结构的同侧表征。我们使用脑磁图(MEG)来检查人类嘴唇和舌头的皮质表现，并检查来自这些结构的双边输入的相互作用的时间进程。69%的上唇、85%的下唇和88%的舌头受到触觉刺激，出现同侧激活。在对侧半球，口腔结构图与非人类灵长类动物的口腔结构图趋于一致，尽管差异很大，来源位置彼此之间没有统计学上的显著差异。在激活潜伏期方面，ipsi与对侧反应(约30毫秒)，以及来自IPSI和对侧刺激的皮质来源往往位于一起。双侧和单侧刺激的差异激活比S 1号的激活时间晚，约110ms，并局限于侧脑沟的上岸。我们的发现表明，与非人类灵长类动物不同，人类在3b/1中有同侧的嘴唇表示，可能与语音清晰度所需的精确操作有关。单细胞和单细胞的不同激活模式。双侧刺激暗示了一种独特的神经机制，即通过中线整合来自口腔的输入。(C)2003年Wiley-Liss，Inc.
Anterior parietal somatosensory areas 3a, 3b, 1, and 2 generally contain cells with receptive fields that are on the contralateral body. However, inputs from midline structures such as the mouth must be uniquely integrated across the midline. This hypothesis is supported by studies of these fields from nonhuman primates that demonstrate ipsilateral representations of oral structures. We used magnetoencephalography (MEG) to examine the cortical representations of the lips and tongue in humans and to examine the time course of interaction of bilateral inputs from these structures. Ipsilateral activation was observed in response to tactile stimulation of the upper lip in 69% of cases, the lower lip in 85% of cases, and the tongue in 88% of cases. In the contralateral hemisphere, the map of oral structures tended to be in agreement with that from nonhuman primates, although variation was large and source locations were not statistically significantly different from each other. There were no differences in latency of activation for ipsi-vs. contralateral responses (about 30 msec), and cortical sources from ipsi-and contralateral stimulation tended to be located together. Differential activation for bilateral vs. unilateral stimulation occurred later than activation in S 1, around 110 msec, and was localized to the upper bank of the Sylvian sulcus. Our findings indicate that, unlike nonhuman primates, humans have an ipsilateral representation of the lips in 3b/1, possibly related to the precise manipulation necessary for the articulation of speech. The distinct pattern of differential activation for uni-vs. bilateral stimulation suggests a unique neural mechanism of integration across the midline for inputs from the mouth. (C) 2003 Wiley-Liss, Inc.