NEUROANATOMY OF THE AUDITORY SYSTEM

听觉系统的神经解剖学

• 批准号: 3395704
• 负责人: Nell B. Cant
• 金额: $ 15.03万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1978
• 资助国家: 美国
• 起止时间: 1978-07-01 至 1993-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3395704
• 关键词: acoustic nerve; auditory feedback; auditory nuclei; auditory pathways; axon; binaural hearing; cats; cochlea; electron microscopy; gerbil /jird; histochemistry /cytochemistry; inferior colliculus; microscopy; neural information processing; neural inhibition; neural initiation; neuroanatomy; neuronal transport; olivocochlear bundle; sonar; stimulus /response; synapses

The long-term objective of this project is to understand the anatomical basis for sound localization. Two important cues for the localization of sounds are differences at the two ears in the time of arrival and in the intensity of acoustic stimuli. The goal of this proposal is to study the synaptic connections between the spherical and globular cells of the cochlear nucleus and the neurons in the superior olivary complex that appear to be involved in analyzing these binaural cues. The spherical and globular cells receive monaural inputs, but their axons converge onto single neurons in the lateral and medial superior olivary nuclei, where information from the two sides can be compared. Neurons in the lateral superior olivary nucleus (LSO) respond best to interaural differences in the intensity of a stimulus, whereas neurons in the medial superior olivary nucleus (MSO) respond best to specific interaural differences in the time of arrival of a stimulus. These response properties of the neurons in the LSO and MSO depend on the integration of excitatory and inhibitory synaptic inputs. The thesis of this application is that, although the response properties of the neurons in the LSO and MSO to binaural stimuli are different, both get their excitatory and inhibitory inputs from essentially the same sources in the cochlear nucleus. The differences, then, must depend in large part on differences in the synaptic organization of the inputs. Studies of these differences in the MSO and LSO will contribute to an understanding of the mechanism of integration of excitatory and inhibitory synaptic inputs in the mammalian central nervous system. The specific aims of this application can be summarized as follows: (1) To analyze the synaptic organization of the lateral nucleus of the trapezoid body, a nucleus that may project to the MSO and represent a source of inhibitory input; (2) To characterize the putative inhibitory projections from the lateral nucleus of the trapezoid body into the medial superior olivary nucleus; and 3) To compare the excitatory and inhibitory projections to the MSO and LSO in order to identify differences in the synaptic organization that could lead to the different response properties characteristic of these two nuclei. Methodology used to achieve these aims will include electron microscopy of both normal and experimental material and neuroanatomical tracing techniques based on axonal transport.

该项目的长期目标是了解 声音定位的解剖基础。 两个重要的提示 声音的本地化是两只耳朵的差异 到达的时间和声学刺激的强度。 目标 该建议的是研究 耳蜗核的球形和球状细胞和球形细胞 上橄榄络合物中似乎涉及的神经元 在分析这些双耳线索时。 球形和球状细胞 接收单声道输入，但它们的轴突汇聚到单个 外侧和内侧上橄榄核中的神经元，其中 可以比较来自双方的信息。 神经元中的神经元 侧向上橄榄核（LSO）对室内的反应最佳 刺激强度的差异，而神经元中的神经元 内侧上橄榄核（MSO）对特定的反应最佳 刺激到达时间的差异差异。 这些 LSO和MSO中神经元的响应特性取决于 兴奋性和抑制性突触输入的整合。 这 该应用程序的论点是，尽管响应 LSO和MSO中神经元的特性到双耳刺激 不同，都从 在耳蜗核中基本相同的来源。 这 因此，差异必须在很大程度上取决于 输入的突触组织。 这些差异的研究 在MSO和LSO中，将有助于理解 兴奋性和抑制性突触的整合机理 哺乳动物中枢神经系统的输入。 本申请的具体目的可以总结如下： （1）分析的突触组织 梯形体，一种可能向MSO投射的核 代表抑制输入的来源； （2）表征 从侧向核的推定抑制投影 梯形体进入内侧橄榄核；和3）到 将兴奋性和抑制性预测与MSO进行比较 LSO为了确定突触组织的差异 这可能导致不同的响应属性特征 在这两个核中。 用于实现这些目标的方法将 包括正常和实验的电子显微镜 基于轴突的材料和神经解剖示踪技术 运输。