INFORMATION CHANNELS IN THE VESTIBULAR NERVE

描述：拟议中的研究涉及头部运动的控制 通过前庭系统。这样的动作在姿势上起着至关重要的作用 反射和头颅感觉器官的方向，但我们不知道是如何 这些运动是在中枢神经系统内组织起来的。 男性前庭结肠功能异常与 姿势调节缺陷是衰老的常见后遗症， 导致依赖、社会孤立和抑郁。 为了了解前庭对头部运动的控制，我们需要知道 前庭神经的功能成分及其作用 在控制姿势和凝视方面发挥作用。已经完成的实验中 我正在刻画前庭的形态分类 斯氏大鼠的传入神经元及其突触前毛细胞。建议数 研究将扩展对前庭机制的这种分析。我会(1) 重建和量化前庭传入神经的结构 完全被细胞内注射的生物细胞素和 具有生理特征的；(2)使用连续的截面光和电子 用细胞外填充的传入纤维显微镜观察中枢 每种传入类型之间的突触接触；(3)使用双重标记 电子显微镜观察它们之间突触接触的特征 传入类型和前庭脊髓神经元的各种群。这个 本实验的目的是了解其结构机制。 来自每种传入类型的信号在其第一个中枢被转换 Synapse。 这项研究，结合正在进行的工作，将有助于我们的 从三个方面了解前庭机制。首先，它将 极大地扩展了我们对前庭信息通道的理解 很有胆量。其次，它将对我们的理解提供重要的补充 前庭控制系统的下降。第三，它将帮助我们理解如何 头部和颈部的反射是协调的，以实现姿势和视觉 在不断运动的世界中保持稳定。

DESCRIPTION: The proposed research deals with the control of head movements by the vestibular system. Such movements play an essential role in postural reflexes and the orientation of cranial sense organs, but we do not know how these movements are organized within the central nervous system. Abnormalities in vestibulocollic function in man are associated with deficits in postural regulation and are common sequelae of aging, contributing to dependence, social isolation, and depression. To understand vestibular control of head movements we need to know the functional components of the vestibular nerve and the role each component plays in the control of posture and gaze. In experiments already completed or underway I am characterizing the morphological classes of vestibular afferents in P. scripta and their presynaptic hair cells. The proposed research will extend this analysis of vestibular mechanisms. I Will (1) reconstruct and quantify the architecture of vestibular afferents that have been completely filled by intracellular injections of biocytin and characterized physiologically; (2) use serial section light and electron microscopy of extracellularly filled afferents to identify the central synaptic contacts between each afferent type; (3) use double labeling electron microscopy to characterize the synaptic contacts between each afferent type and the various populations of vestibulospinal neurons. The object of the experiments is to learn the structural mechanisms by which signals from each afferent type are transformed at their first central synapse. This research, combined with work in progress, will contribute to our understanding of vestibular mechanisms in three ways. First, it will greatly expand our understanding of information channels in the vestibular nerve. Second, it will provide an important addition to our understanding of descending vestibular control. Third, it will help us understand how head and neck reflexes are coordinated to achieve postural and visual stability in the world of constant motion.