FUNCTIONAL ANATOMY OF THE SOMATOSENSORY CORTEX OF MONKEYS

在一系列的解剖学实验中，我们确定了两条途径 躯体感觉信息到达边缘结构的重要途径 用于躯体记忆。一条路线从邮局中心背部开始 穿过后顶叶皮质，可以接触到边缘 系统通过扣带回皮质。这条途径可能在功能上 类似于枕顶路径的空间视觉。一个 第二条路线从后中央地带通过SII腹侧 到岛叶皮质，然后到杏仁核，然后间接到 海马体通过鼻皮质。我们现在有证据表明 第二径路类似于物体的枕颞径 幻象。我们的神经行为证据表明双侧岛状突起 损伤会导致严重的触觉识别缺陷，与 这表明岛叶皮质是一种 触觉识别的顶叶-胰岛素-边缘通路等 与枕颞缘TE区相似的位置 视觉识别的途径。通过记录神经元的活动 大脑半球中的SII，接受大脑半球选定部分的病变 后中央体表象，我们展示了 来自SII的对应表示，指示连续流 从中央后带到SII的信息。一个意想不到的发现 在这项研究中，在中央后部损害之后， 失活的SII区经历了重大的功能重组。在……里面 另一个实验我们记录了中枢后叶的神经元活动。 在4只猴子10-12年后剥离背根代表 上肢被切断。结果表明，整个 上肢的代表已经被一张扩大的脸所取代 表示法，大于数量级的展开 之前人们认为这是可能的。这两个实验都涉及到 中枢神经系统的紊乱，导致先前的 成年哺乳动物皮质可塑性的未知程度和 表明中央银行之后重组的可能性更大 而不是外周神经系统操作。

In a series of anatomical experiments, we have identified two routes by which somatosensory information reaches limbic structures important for somatic memory. One route courses dorsally from the postcentral strip through posterior parietal cortex and has access to the limbic system via cingulate cortex. This pathway may be functionally analogous to the occipitoparietal pathway for spatial vision. A second route courses ventrally from the postcentral strip through SII to the insular cortex and then to the amygdala and indirectly to the hippocampus through rhinal cortex. We now have evidence that this second pathway is analogous to the occipitotemporal pathway for object vision. Our neurobehavioral evidence indicates that bilateral insular lesions cause a severe tactile recognition deficit, consistent with the suggestion that insular cortex is a critical link in a parieto-insulo-limbic pathway for tactile recognition, and so occupies a position analogous to that of area TE in the occipito-temporo-limbic pathway for visual recognition. By recording neuronal activity from SII in hemispheres that received lesions of selected portions of the postcentral body representation, we demonstrated a loss of the corresponding representation from SII, indicating a serial flow of information from the postcentral strip to SII. An unexpected finding in this study was that, following a postcentral lesion, the deactivated SII region undergoes major functional reorganization. In another experiment we recorded neuronal activity from the postcentral strip in 4 monkeys 10-12 years after the dorsal roots representing the upper limb were severed. The results indicated that the entire representation of the upper limb had been replaced by an expanded face representation, an expansion an order of magnitude greater than previously thought possible. Both of these experiments, involving perturbations of the central nervous system, resulted in a previously unrecognized degree of cortical plasticity in adult mammals and suggest that the potential for reorganization is greater after central than peripheral nervous system manipulations.