SENSORY PROCESSING AND ITS RELATION TO ORAL-FACIAL PAIN

中枢神经系统中的感觉处理包括 和下行通路。 例如，上升的伤害性冲动， 中度口面部疼痛，受到下行控制系统的影响 主要来源于脑干 在视觉系统中， 视网膜的脉冲受到下行控制系统的影响 起源于大脑皮层 拟议的研究审查了 下行调节通路和上行感觉通路。 一阶段 下降到上级丘的纤维来自一个宽的 纹状体前颞叶和顶叶皮层的扩张 电生理 对猴子的行为研究表明， 在视觉运动整合中起着重要的调节作用。 个人 这个系统的组成部分来自每个已知的细分， 视觉皮层 皮质顶盖细胞的每一个组成部分可以形成一个独特的 细胞亚群的视区，从他们 起源。 我们在第一阶段的目标是审查其中一个组成部分，即， 来自纹外区MT的皮质-顶盖通路。 视觉反应 MT中单个皮质顶盖细胞的特性将用 微电极记录在麻醉的猴子，并比较了一个 不投射到丘的MT细胞的对照群体。 第二阶段。 来自口腔的上行伤害性信息是 由浅层的长投射神经元传递到丘脑 脊髓背角的第五层和第五层。 第二阶段的目标是 以确定无髓鞘初级传入神经是否与 第五层三叉神经丘脑细胞，鉴别出三叉神经丘脑神经元 通过对侧丘脑的逆向激活， 辣根过氧化物酶（HRP），和无髓鞘的初级 传入纤维将用注射的正向转运HRP标记 进入背根神经节 充满细胞的形态特征 将描述这些细胞之间的突触相互作用， 将分析标记的终端。

Sensory processing in the central nervous system involves both ascending and descending pathways. For example, ascending nociceptive impulses which mediate oral-facial pain, are influenced by descending control systems originating mainly in the brain stem. In the visual system, ascending impulses from the retina are influenced by descending control systems originating in the cortex. The proposed research examines both a descending modulatory pathway and an ascending sensory pathway. Phase I. Fibers descending to the superior colliculus arise from a wide expanse of prestriate, temporal and parietal cortex. Electrophysiological and behavioral studies in monkeys indicate that this corticotectal system plays an important modulatory role in visuomotor integration. Individual components of this system descend from each of the known subdivisions of visual cortex. Corticotectal cells of each component may form a unique subpopulation of cells within the visuotopic area from which they originate. Our goal in Phase I is to examine one such component namely, the corticotectal pathway from extrastriate area MT. The visual response properties of individual corticotectal cells in MT will be examined with microelectrode recordings in the anesthetized monkey, and compared to a control population of MT cells which do not project to the colliculus. Phase II. Ascending nociceptive information from the oral cavity is relayed to the thalamus by long projection neurons in the superficial layers and lamina V of the medullary dorsal horn. Our goal in Phase II is to determine whether unmyelinated primary afferents synapse on trigeminothalamic cells of lamina V. Trigeminothalamic neurons, identified by antidromic activation from the contralateral thalamus, will be filled with horseradish peroxidase (HRP), and terminals of unmyelinated primary afferent fibers will be labeled with orthogradely transported HRP injected into the dorsal root ganglion. The morphological features of filled cells will be described and the synaptic interaction between these cells and labeled terminals will be analyzed.