Sensory Coding Among Semicircular Canal Afferent Neurons

描述：(申请人提供)本次调查致力于阐明头部运动是如何 编码于初级传入神经元的放电特征 支配前庭迷路的半规管脊。它的 另一个目标是显示这个神经代码是如何分布在 小脑皮层。这些实验旨在确定动态程度如何 反映在宽带系统传递函数中的响应特性 在一种描述前庭传入感受野的新方法中， 是相对于整个传入合奏分布的。一个 形态生理学策略将显示这些系统如何响应特征 被映射到外周脊神经上皮细胞上。实验也是 旨在确定传入的空间和时间编码在 前庭苔藓传入纤维投射至腹侧悬垂和前庭 小脑皮质的结节。这些研究的结果将阐明 半规管传入系统的感觉编码基础，以及 解释传入生理多样性对生物多样性的贡献的依据 在小脑内进行处理。随后的地图也将提供这座桥 在外周受体的研究和功能编码的基础上 传入神经元，它将提供一个功能上下文，用来 解读毛细胞生理学和病理生理学研究 前庭周围病变。 在这次调查中要进行的实验利用 哺乳动物的电生理记录和细胞内标记方法 模型来识别与以下各项相关的感觉编码特征 传入神经元的特殊形态和生理特征。 将进行广泛的电生理记录以阐明 传入群体中传入反应动力学的连续体。这些是 在这些神经元的感受野模型的背景下进行分析，在 该个体传入头部运动状态空间区域的编码。 传入性反应动力学的研究是关于 脊内的神经支配，以及它们在 小脑悬垂和小结。这些实验将揭示新的洞察力 关于刺激编码在感官中的基本组织 系统。

DESCRIPTION:(provided by applicant) The present investigation is dedicated to elucidating how head movements are encoded in the discharge characteristics of primary afferent neurons innervating the semicircular canal cristae of the vestibular labyrinth. Its additional objective is to show how this neural code is distributed within the cerebellar cortex. The experiments are designed to determine how dynamic response characteristics, as reflected in broad-band systems transfer functions and in a novel approach to characterizing vestibular afferent receptive fields, are distributed with respect to the entire afferent ensemble. A morphophysiology strategy will show how these systems response characteristics are mapped onto the peripheral crista neuroepithelium. Experiments are also designed to determine how afferent spatial and temporal coding is reflected in the projections of vestibular afferent mossy fibers to the ventral uvula and nodulus of the cerebellar cortex. The results from these studies will elucidate the foundation of sensory coding in the semicircular canal afferent system, and the bases to interpret the contribution of afferent physiologic diversity to processing within the cerebellum. The ensuing maps will also provide the bridge between investigations of the peripheral receptor and the functional coding in the afferent neurons, which will provide a functional context with which to interpret studies of hair cell physiology and pathophysiologic investigations of peripheral vestibular lesions. The experiments to be conducted in this investigation utilize electrophysiologic recording and intracellular labeling methods in a mammalian model to identify the features of sensory coding that are associated with specific morphologic and physiologic characteristics of the afferent neuron. Extensive electrophysiologic recordings will be conducted to elucidate the continuum of afferent response dynamics among the afferent ensemble. These are analyzed in the context of a model of receptive fields for these neurons, in which individual afferents code for a region of head-movement state space. Afferent response dynamics are investigated with respect to the locus of innervation within the crista, and with respect to their terminations within the cerebellar uvula and nodulus. These experiments will reveal new insight regarding the fundamental organization of stimulus coding in this sensory system.