Integration of Inputs in the Inferior Colliculus

下丘输入的整合

• 批准号: 6881264
• 负责人: KEVIN A DAVIS
• 金额: $ 27.81万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-05-01 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6881264
• 关键词: auditory nuclei; auditory pathways; auditory stimulus; biological signal transduction; brain stem; cats; cell component structure /function; computer simulation; cues; decerebration; electrophysiology; histology; inferior colliculus; mesencephalon; neural information processing; neural inhibition; neuroanatomy; olivary body; pharmacology; single cell analysis; sound perception; statistics /biometry; stimulus /response; synapses

DESCRIPTION: (Adapted from the Investigator's Abstract) The inferior colliculus occupies a pivotal position in the central auditory system; it receives direct inputs from all of the major auditory brainstem nuclei and, in turn, it provides nearly all of the input to the auditory forebrain. Anatomical evidence suggests that the brainstem projections to the central nucleus of the inferior colliculus (ICC) form highly organized synaptic domains with both segregated and shared sources of input. The long-term objective of this research is to determine how these convergence patterns create discrete pathways for the optimal processing of biologically relevant acoustic information. In support of this parallel processing model, our recent electrophysiological studies have discovered three principal ICC response types that appear to be uniquely specialized for the neural encoding of spectral cues for sound localization, narrowband signals in noise, and binaural level and timing information. Based on correlations with response properties in lower-order nuclei, it has been hypothesized that each ICC unit type reflects a dominant excitatory input from either the medial superior olive, the lateral superior olive or the dorsal cochlear nucleus. Experiments of Aims 1-3 in this application are designed to provide direct evidence for theses functional connections. Our proposed multidisciplinary approach combines single-unit recording techniques, cross-correlation analyses, and pharmacological manipulations to determine the relative strength and topographic distribution of the putative inputs to the different ICC response types. After these initial investigations describe the anatomical pathways that link the auditory midbrain to the brainstem, experiments of Aim 4 will explore the functional consequences of this synaptic organization by comparing the quantity of acoustic representations in ICC target neurons and their sources of input. A question of particular interest in these later experiments is how the ascening inputs to the ICC interact with each other and a rich intrinsic inhibitory circuitry to enhance the processing of sound localization information. This research will provide currently unknown details regarding auditory processing within the inferior colliculus, and will establish a basic theoretical foundation for future electrophysiological studies of information streaming within the central nervous system.

描述：（改编自调查员的摘要） 在中央听觉系统中占据关键位置；它直接收到 来自所有主要听觉脑干核的输入，然后 提供了几乎所有输入的听觉前脑。解剖学证据 表明脑干向下核的脑部投影 Colliculus（ICC）形成高度有组织的突触域，两者都分离 和共享的输入来源。这项研究的长期目标是 确定这些收敛模式如何创建离散途径 生物学相关的声学信息的最佳处理。支持 这种并行处理模型，我们最近的电生理研究具有 发现了三种主要的ICC响应类型，它们似乎是独特的 专门用于频谱提示的神经编码，以进行声音定位， 噪声，双耳级别和定时信息中的窄带信号。基于 关于与低阶核中响应特性的相关性，它已经 假设每种ICC单位类型都反映了来自 内侧上橄榄，横向上橄榄或背侧 耳蜗核。本应用程序中的目标1-3实验旨在 为这些功能连接提供直接证据。我们提出的 多学科方法结合了单单元记录技术， 互相关分析和药理操作以确定 推定输入的相对强度和地形分布 不同的ICC响应类型。这些初步调查描述了 将听觉中脑与脑干联系起来的解剖途径， AIM 4的实验将探索该突触的功能后果 通过比较ICC中的声学表示数量 靶向神经元及其输入来源。一个特别感兴趣的问题 这些后来的实验是ICC的升级输入如何与 彼此和丰富的内在抑制作用以增强处理 声音本地化信息。这项研究将提供当前未知的 有关下丘中听觉处理的详细信息，并将 建立未来电生理学的基本理论基础 中枢神经系统中信息流的研究。