Burton H, Mitchell G, Brent D
J Comp Neurol. 1982 Sep 10;210(2):109-35. doi: 10.1002/cne.902100203.
The cortex of the anterior ectosylvian gyrus and adjoining ectosylvian and suprasylvian sulci was explored with tungsten microelectrodes to determine the distribution of responses to light cutaneous stimulation in barbiturate-anesthetized cats. Recordings were spaced between 125 and 250 micrometers and, in several cases, nearly all of the somatic areas in this cortex were explored in the same brain. Four somatic sensory areas were identified on the basis of responses properties, sequences of receptive fields, and cytoarchitecture. The largest area, which occupied the rostral and medial two-thirds to three-fourths of the exposed, relatively flat portion of the anterior ectosylvian gyrus, was called the second somatic sensory area (SII). Receptive fields in SII were primarily from the contralateral side of the body; they were well defined and somatotopically organized into an erect representation of the body. The top of the head was located next to a similar representation of the periphery in a portion of the first somatic sensory area (SI). Individual distal digits and toes occupied discrete components of the SII map. Another representation for the distal forelimb and hindlimb was noted medially along the lateral bank of the anterior suprasylvian sulcus. Receptive fields and response properties in this region were equivalent to those seen in SII proper. However, only a crude anteroposterior, fore- to hindlimb topographical organization was noted, but with more distal parts of the limbs generally located closer to the fundus of the sulcus in this medial representation. As the cytoarchitecture in this medial region was similar to the rest of SII it was considered a medial subdivision of SII. A third, topographically organized zone was located lateral to SII largely within the upper bank of the anterior ectosylvian sulcus and adjoining lateral crest of the anterior ectosylvian gyrus. Large, stockinglike, contralateral receptive fields were common; ipsilateral components to the receptive fields were present. Some individual digit receptive fields were located in the rostral part of the forelimb zone within the anterior ectosylvian sulcus. This lateral somatic area is probably equivalent to a fourth somatic sensory area (SIV) recently identified by Clemo and Stein ('82). Posterior to the hindlimb zones of SII and medial to SIV was another region that responded to cutaneous plus auditory stimulation. There was no detectable topography in this area; nearly all of the receptive fields were large, frequently bilateral, and often involved the whole body or all four extremities. This area's cytoarchitecture was comparable to previous descriptions of the suprasylvian fringe (Rose, '49). The location and physiology of these four areas were discussed in reference to previous controversies regarding the topography of the body representation in SII and the location of an acallosal zone in this region of cortex.
用钨微电极探查前外侧薛氏回皮质及其相邻的外侧薛氏沟和薛氏上沟，以确定在巴比妥麻醉猫中对皮肤轻刺激反应的分布。记录间隔为125至250微米，在几个案例中，同一大脑中几乎所有该皮质的躯体区域都被探查过。根据反应特性、感受野序列和细胞结构，确定了四个躯体感觉区。最大的区域占据了前外侧薛氏回暴露的、相对平坦部分的嘴侧和内侧三分之二至四分之三，被称为第二躯体感觉区（SII）。SII中的感受野主要来自身体的对侧；它们界限清晰，按躯体定位组织成身体的直立表征。头顶位于第一躯体感觉区（SI）一部分中类似周边表征的旁边。单个远端手指和脚趾占据SII图谱的离散部分。在前薛氏上沟外侧壁内侧还发现了远端前肢和后肢的另一种表征。该区域的感受野和反应特性与SII本身所见的相当。然而，仅观察到粗略的前后、前肢到后肢的地形组织，但在这种内侧表征中，肢体的更远端部分通常更靠近沟底。由于该内侧区域的细胞结构与SII的其余部分相似，因此被认为是SII的内侧亚区。第三个按地形组织的区域位于SII外侧，主要在前外侧薛氏沟的上壁内以及相邻的前外侧薛氏回外侧嵴。大的、类似长袜的对侧感受野很常见；感受野中存在同侧成分。一些单个手指感受野位于前外侧薛氏沟内前肢区的嘴侧部分。这个外侧躯体区域可能相当于Clemo和Stein（1982年）最近确定的第四躯体感觉区（SIV）。在SII的后肢区后方和SIV内侧是另一个对皮肤加听觉刺激有反应的区域。该区域没有可检测到的地形；几乎所有感受野都很大，经常是双侧的，并且经常涉及整个身体或所有四肢。该区域的细胞结构与之前对薛氏上回边缘的描述相当（Rose，1949年）。参照先前关于SII中身体表征地形和该皮质区域无胼胝体区位置的争议，讨论了这四个区域的位置和生理学特性。
