PROCESSING OF BILATERAL INPUTS TO VESTIBULAR NUCLEUS

描述：（改编自研究者摘要）这是一份修订版 申请（R 01 03894- 01 A），描述了使用体外 附连颞骨的脑标本，用于研究最初的前庭 脊椎动物脑干的加工过程。首席研究员最初 开发了这些创新的技术来研究视觉输入的反射路径 来稳定视网膜图像。在这个拨款申请中，只有头部旋转 将在前庭核中研究反应。全细胞斑片记录 这些反应将被检查之前和之后，单向可逆 利多卡因使第八神经失活。 同侧单突触兴奋性管传入纤维会聚于神经元 前庭神经核多突触输入也被认为是达到相同的 来自对侧神经管的神经元具有相应的旋转轴。 前庭核神经元也显示几种反应类型在自然过程中， 头部水平旋转。细胞会对运动做出反应， 记录及其尖峰放电可以编码头部的速度或 加速度为了阐明前庭神经系统的神经回路， 核，从第八神经传入和两个核之间， 将对单个突触事件进行高分辨率贴片记录， 头部旋转和电神经刺激引起兴奋性和/或 抑制途径突触药物应用的影响将有助于识别 参与单突触和多突触回路的神经递质。 将分析前庭核细胞的膜特性， 它们是如何修改这些突触输入， 前庭反应类型 来自两个丘脑的冗余感觉输入对于改善前庭功能是有用的。 敏感性和补偿单方面损失。该项目分析 这些双边投入，以了解它们在自然资源中的作用， 导致正常平衡感或产生 在病理状态下眩晕。

DESCRIPTION: (Adapted from the Investigator's Abstract) This is a revised application (R01 03894-01A) that describes novel experiments using an in vitro brain preparation with attached temporal bones to study the initial vestibular processing of the vertebrate brainstem. The Principal Investigator initially developed these innovating techniques to study visual inputs to reflex paths that stabilize the retinal image. In this grant application, only head rotation responses will be studied in the vestibular nuclei. Whole-cell patch recordings of these responses will be examined before and after unilateral reversible lidocaine inactivation of the eighth nerve. Ipsilateral monosynaptic excitatory canal afferents converge onto neurons in the vestibular nucleus. A polysynaptic input is also thought to reach the same neurons from a contralateral canal with the corresponding axis of rotation. Vestibular nucleus neurons also display several response types during natural horizontal head rotation. Cells respond to motion to or away from the side of the recording, and their spike discharges can encode the head's velocity or acceleration. To elucidate the underlying neural circuitry of the vestibular nuclei, from the eighth nerve afferents and between the two nuclei, high-resolution patch recordings of individual synaptic events will be made as head rotation and electrical nerve stimulation evoke the excitatory and/or inhibitory pathways. Effects of synaptic drug applications will help identify the neurotransmitters involved in the monosynaptic and polysynaptic circuits. The membrane properties of the vestibular nucleus cells will be analyzed to see how they modify those synaptic inputs to yield the spike output of different vestibular response types. Redundant sensory input from both labyrinths is useful to improve vestibular sensitivity and to compensate for a unilateral loss. This project analyzes these bilateral inputs to gain an understanding of their role in the natural processing that results in a normal sense of balance or produces the feeling of vertigo during a pathological condition.