SENSORIMOTOR CORTEX IN PROSIMIAN PRIMATE

所有哺乳动物物种似乎都有两个主要的躯体感觉投射。 大脑皮层感觉运动区、SMI和SmII区。 这两个投影区都接受来自 对侧身体表面，但最突出的是从手。单边 SMI或SMII手部区域的损害会导致严重的行为缺陷 纹理辨别能力。然而，细胞的响应特性 在这两个区域，非灵长类物种表明它们可能对 不同于区分时空特征的能力 纹理曲面。对感觉运动皮质和 灵长类的触觉功能，我们打算研究Galago以确定：1) SmII的生理组织和细胞构筑特征；2) 选择性去除SMI或SmII后的纹理辨别缺陷 手部无毛区域；3)Smi和SmII神经元对 正常情况下手持式点状刺激和鼓旋转纹理表面 动物。在这些多学科研究中，我们将研究 SMI和SMII对纹理识别能力的贡献，AS 由皮质损伤的行为后果和由 组成神经元的生理特性。我们提出了这些研究 在加拉戈，因为它是一种灵长类物种，Smi和SmII都比 组织简单，比Macaca和其他地方更容易访问 类人灵长类动物。然而，我们预计SI和SII的结果将在 Galago可以推广到更复杂和最近进化的灵长类动物。 这些关于触觉辨别的生理基础的研究是 期望在知觉中展示特定的神经机制 现象。对躯体感觉的神经基础的理解 感知异常在精神病学和精神病学中如此常见的意义 神经紊乱。

All mammalian species appear to have two major somatic sensory projection areas in the sensorimotor region of the cerebral cortex, SmI and SmII. Both projection areas receive low-threshold cutaneous input from the contralateral body surface, but most prominantly from the hand. Unilateral lesions of the SmI or SmII hand areas produce severe behavioral deficits in texture discrimination capacity. However the response properties of cells in these two areas in non-primate species suggest they may contribute differently to the ability to discriminate the spatiotemporal features of textured surfaces. With a continuing interest in sensorimotor cortex and tactile function in primates, we intend to study Galago to determine: 1) the physiological organization and cytoarchitectonic features of SmII; 2) texture discrimination deficits following selective removal of SmI or SmII glabrous hand areas; 3) the response properties of SmI and SmII neurons to hand-held punctate stimuli and to drum-rotated textured surfaces in normal animals. In these multidisciplinary studies we will examine the conributions of SmI and SmII to texture discrimination capacity, as suggested by behavioral consequences of cortical lesions and by the physiological properties of constituent neurons. We proposed these studies in Galago, as it is a primate species in which both SmI and SmII are more simply organized and more easily accessible than in Macaca and other anthropoid primates. However, we expect the findings of SI and SII in Galago to be generalizable to more complex and recently-evolved primates. These studies of the physiological basis of tactile discrimination are expected to demonstrate specific neural mechanism in perceptual phenomenon. An understanding of neural basis for somatic sensation has significance for perceptual abnormalities so common in psychiatric and neurological disorders.