SYNAPTIC ORGANIZATION OF THE AUDITORY SYSTEM

听觉系统的突触组织

• 批准号: 2125024
• 负责人: DOUGLAS L OLIVER
• 金额: $ 26.56万
• 依托单位: UNIVERSITY OF CONNECTICUT SCH OF MED/DNT
• 依托单位国家: 美国
• 财政年份: 1982
• 资助国家: 美国
• 起止时间: 1982-04-01 至 1998-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2125024
• 关键词: afferent nerve; auditory pathways; auditory stimulus; binaural hearing; cats; guinea pigs; immunocytochemistry; inferior colliculus; innervation; laboratory rat; neural information processing; neuroanatomy; neuronal transport; olivary body; psychoacoustics; synapses; transmission electron microscopy

This research will identify the innervation patterns and synaptic organization that underlie binaural and monaural processing in the auditory brainstem. The present proposal will focus specifically on the pathways that underlie binaural hearing, those from the cochlear nucleus (CN) to the inferior colliculus (IC) via the superior olivary complex (SOC). Each experiment will use intracellular-like anterograde filling and/or intracellular injections of identified neurons in a brain slice. Each experiment will identify structure/function relationships in the medial superior olive (MSO), in the IC, or in the covering ascending pathways to the IC. Aim 1. To determine how the innervation and synaptic organization of MSO create binaural time sensitivity. The neural circuity from the anteroventral CN (AVCN) to the MSO will be visualized. The experiments will: (A) Completely fill the axons from the AVCN with dextran and completely reconstruct their projections to the SOC. (B) Use a brain slice to fill neurons in MSO whose axons project to the IC and study their innervation by AVCN axons labeled with dextran. There may be rostra-caudal differences in axon branching, length, diameter, myelination, and topography that may underlie the delay-line mechanism. Aim 2. To determine how the MSO transfer intermural time differences (ITD) information to the IC. A topographical projection from MSO to the IC is hypothesized. Within this target zone, the synaptic organization of the IC may play an important role in maintaining ITD sensitivity. To test this: (A) Injections of anterograde markers in the MSO will determine the topography of the projection to the IC. Recordings of IC neurons in vivo will relate the responses to the terminal fields of MSO axons. (B) Intracellular filling will identify specific neuron types in the IC and their innervation by MSO afferent will be determined in a brain slice preparation. The projection from MSO may provide anatomical evidence for a spatial map of azimuth in the IC. This projection may be segregated into only part of the low-frequency IC, and it may not innervate each cell type similarly. Aim 3. To establish how the innervation and synaptic organization of IC integrates the MSO inputs with the binaural and monaural inputs from other sources. Injections of two anterograde markers will be made: one in MSO and a second in another brainstem nucleus. MSO inputs may remain separate from other inputs from contralateral LSO, contralateral AVCN, and contralateral DNLL. These experiments will demonstrate which afferent systems coverage and which remain segregated in the IC.

这项研究将确定神经支配模式和突触 组织的组织是双耳和单文处理的基础 听觉脑干。 本提案将专门针对 双耳听力的途径，来自人工耳蜗核的途径 （CN）通过上橄榄络合物到下丘（IC） （SOC）。 每个实验都将使用细胞内的顺序填充 和/或细胞内注射脑切片中已鉴定的神经元。 每个实验将确定在 内侧上橄榄（MSO），在IC中或覆盖率上升 通往IC的途径。 目标1。确定MSO的神经支配和突触组织如何 创造双耳时间灵敏度。 来自 将可视化到MSO的前腹CN（AVCN）。 实验 威尔：（a）完全填充AVCN的轴突，并用葡聚糖和 完全重建对SOC的预测。 （b）使用大脑 切片以填充MSO的神经元，其轴突向IC进行了项目和研究 它们由用葡聚糖标记的AVCN轴突支配。 可能有 轴突分支，长度，直径，直径的Rostra-caudal差异， 髓鞘形成和地形可能是延迟线机制的基础。 目的2。确定MSO如何传递层间时间差异 （ITD）信息到IC。 从MSO到的地形投影 IC是假设的。 在此目标区域内，突触组织 IC的中断可能在维持ITD敏感性中起重要作用。 到 测试以下测试：（a）在MSO中注射顺行标记 确定投影对IC的地形。 IC的录音 体内神经元将与MSO的末端场的响应联系起来 轴突。 （b）细胞内填充将确定特定的神经元类型 MSO传入的IC及其神经支配将在A中确定 大脑切片准备。 MSO的投影可能会提供解剖学 IC中方位角空间图的证据。 这个投影可能是 仅隔离为低频IC的一部分，并且可能不会 类似地支配每种单元格类型。 目标3。建立IC的神经支配和突触组织如何 将MSO输入与来自双耳和单膜输入的输入 其他来源。 将制作两种顺行标记的注射：一个 在MSO中，另一个在另一个脑干核中。 MSO输入可能仍然存在 与其他输入与对侧LSO对侧AVCN分开 和对侧DNLL。 这些实验将证明哪个 传入的系统覆盖范围并在IC中保持隔离。