Studies of the Central Auditory System

中枢听觉系统的研究

• 批准号: 6766932
• 负责人: JOHN R DOUCET
• 金额: $ 24.53万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6766932
• 关键词: acoustic nerve; auditory nuclei; auditory pathways; cell morphology; cell type; guinea pigs; hearing; immunocytochemistry; laboratory rat; neural information processing; olivary body

DESCRIPTION (provided by applicant): Our long-range goal is to understand the neural mechanisms of hearing. All information about sound is encoded by patterns of activity in the auditory nerve. By virtue of its position as the obligatory recipient of auditory nerve input, the cochlear nucleus is a key site to study how acoustic stimuli are translated into neural codes that are then sent to the brain. Cochlear nucleus neurons are organized into definable groups that share common inputs, cellular mechanisms, and axonal targets. By linking structure and function for different cell types, we seek to understand their roles in hearing. Ultimately, this kind of knowledge should allow us to interpret structural anomalies resulting from deafness or noise-induced damage in terms of their effect on acoustic processing. In this application, we propose to study multipolar cells in the ventral division of the cochlear nucleus. The axons of these cells target other neurons in the cochlear nucleus. They also project to nearly every brain stem and midbrain structure in the auditory pathway. Multipolar neurons are comprised of several distinct subclasses of cells. We will use pathway tracing and immunocytochemical techniques to study the structure and neurochemistry of different classes with respect to their axonal targets. We will employ an in vitro preparation of the isolated whole brain to study how the activity within a subclass influences its axonal targets. Information obtained from both types of experiments will result in links between structural and functional data for different cell types. This combined anatomic and physiologic approach to the study of multipolar cells will allow us to determine how their encoded messages are distributed in the brain, will impact models of binaural hearing, and may suggest new designs for human brain stem implants.

描述（由申请人提供）：我们的长期目标是了解听力的神经机制。所有关于声音的信息都是由听觉神经的活动模式编码的。由于其作为听觉神经输入的强制性接受者的地位，耳蜗核是研究声学刺激如何被翻译成神经代码然后发送到大脑的关键部位。尾核神经元被组织成可定义的组，这些组共享共同的输入、细胞机制和轴突靶点。通过将不同类型细胞的结构和功能联系起来，我们试图了解它们在听力中的作用。最终，这种知识应该使我们能够解释耳聋或噪声引起的损伤对声学处理的影响方面的结构异常。在这个应用程序中，我们建议研究多极细胞的腹侧分裂的耳蜗核。这些细胞的轴突以耳蜗核中的其他神经元为目标。它们还投射到听觉通路中的几乎每一个脑干和中脑结构。多极神经元由几个不同的细胞亚类组成。我们将使用路径追踪和免疫细胞化学技术来研究不同类别的轴突靶点的结构和神经化学。我们将采用离体全脑的体外制备来研究亚类内的活动如何影响其轴突靶点。从这两种类型的实验中获得的信息将导致不同细胞类型的结构和功能数据之间的联系。这种结合解剖学和生理学的多极细胞研究方法将使我们能够确定它们的编码信息如何在大脑中分布，将影响双耳听力模型，并可能为人类脑干植入物提出新的设计。