VESTIBULOSPINAL CONTROL OF CERVICAL MOTORNEURONS

这项拟议的研究涉及颈部的神经元控制。 前庭脊髓系统的运动。这样的动作在玩 在姿势反射和定向力中起重要作用 头颅感觉器官，但我们不知道这些运动 是在颈髓内组织的。中的异常现象 人的前庭收缩功能与前庭功能缺陷有关 体位调节是临床常见的后遗症 梅尼埃病等病症。 为了了解前庭对颈部运动的控制，我们需要 知道：(1)组成大脑的神经元群 前庭脊髓系统；(2)各系统的突触关系。 有颈部运动神经元的人群。已经在实验中了 我描述的是已经完成或正在进行的颈部运动神经元。 在我描述的已经完成或正在进行的实验中 颈椎运动池及其一级结构的超微结构 秀丽伪鱼颈部运动神经元的传入。 这项拟议的研究将扩展对颈部肌肉的分析。 控制力。(1)用辣根标记前庭脊髓轴突 过氧化物酶(HRP)及其四种结构的表征 已知具有功能意义的参数： 轴突直径、终茎形态、分枝模式和 突触周围超微结构。(2)突触关系 HRP标记的前庭脊髓轴突与颈椎运动的关系 神经元将在电子显微镜下进行评估。该对象 这些实验的目的是识别不同的形态 将前庭信号传递到颈部的神经元群 并进一步加深我们对运动神经元功能的理解 这些群体中的每一个在组织中扮演的角色 脖子的运动。这项研究，结合正在进行的工作， 将有助于我们在两个阶段中理解宫颈控制 方式。拟议的研究将提供第一个全面的 前庭颈椎的系统形态描述 脊椎动物中的轴突。第二，拟议的研究将 提供有关招聘机制的重要数据 颈部运动神经元。

The proposed research deals with the neuronal control of neck movements by the vestibulospinal system. Such movements play an important role in postural reflexes and the orientation of cranial sense organs, but we do not know how these movements are organized within the cervical spinal cord. Abnormalities in vestibulocollic function in man are associated with deficits in postural regulation and are common sequelae of clinical conditions such as Meniere's disease. To understand vestibular control of neck movements we need to know: (1) the neuronal populations which make up the vestibulospinal system; and (2) the synaptic relations of each population with cervical motor neurons. In experiments already completed or underway I am describing cervical motor neurons. In experiments already completed or underway I am describing cervical motor pools and the ultrastructure of first order afferents to cervical motor neurons in Pseudemys scripta elegans. The proposed research will extend this analysis of cervical muscle control. (1) Vestibulospinal axons will be labelled with horseradish peroxidase (HRP) and characterized in terms of four structural parameters which are known to have functional significance: axon diameter, terminal arbor morphology, branching pattern, and synaptic bouton ultrastructure. (2) The synaptic relations between HRP labelled vestibulospinal axons and cervical motor neurons will be assessed under the electromicroscope. The object of these experiments is to identify the various morphological populations of neurons which relay vestibular signals to cervical motor neurons and to further our understanding of the functional role which each of these populations plays in the organization of neck movements. This research, combined with work in progress, will contribute to our understanding of cervical control in two ways. The proposed research will provide the first comprehensive and systematic morphological description of vestibulo-cervical axons in any vertebrate. Second, the proposed research will provide important data on the mechanisms underlying recruitment of cervical motor neurons.