FUNCTIONAL PATHWAYS OF THE COCHLEAR NUCLEUS

耳蜗核的功能通路

• 批准号: 6379558
• 负责人: JOHN R DOUCET
• 金额: $ 8.18万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-05-01 至 2003-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6379558
• 关键词: auditory nuclei; auditory pathways; brain mapping; cell type; electrophysiology; electrostimulus; histology; laboratory rat; neural information processing; neuronal transport; neurophysiology

Our long term goal is to understand the neural codes and computations that underlie hearing. All acoustic information is presented to the brain with the synapses formed by auditory nerve fibers in the cochlear nucleus. Here, the data contained in the nerve are distributed amongst a variety of cell types that each represent some feature of the acoustic environment. Cochlear nucleus neurons and their neural codes form the foundation of central auditory pathways that are ultimately responsible for our ability to locate and identify a sound: perceptions that collectively we refer to as hearing. How and where the neural computations that underlie these perceptions occur will depend on the axonal pathways engendered by distinct classes of cochlear nucleus neurons, and their synaptic organizations in the structures that they target. In this proposal, we plan to study the axonal pathways borne by one large group of cochlear nucleus neurons referred to as multipolar neurons. We propose that multipolar neurons in the ventral division of the cochlear nucleus play a key role in the initial stages of acoustic information processing. They are full participants in the intrinsic circuitry of the cochlear nucleus and their axons target every brain stem nucleus in the auditory pathway. Multipolar neurons are a heterogeneous population, suggesting that they are comprised of several distinct subclasses of cells. We propose to use retrograde pathway tracing methods to identify the targets of different populations of multipolar neurons, and electrophysiological recording techniques to match the axonal pathway of each type with its physiological response properties. These data will provide new knowledge with respect to the functional roles served by a large group of cochlear nucleus cells, as well as provide insights into the nature of the neural computations performed in central auditory nuclei.

我们的长期目标是了解听证会构成的神经法规和计算。 所有声学信息都以耳蜗核中听觉神经纤维形成的突触呈现给大脑。 在这里，神经中包含的数据分布在各种细胞类型之间，这些细胞类型代表声学环境的某些特征。 耳蜗核神经元及其神经代码构成了中央听觉途径的基础，这些途径最终负责我们定位和识别声音的能力：我们共同称为听力的感知。 这些感知发生的神经计算的方式和地点将取决于由不同类别的耳蜗神经元及其突触组织产生的轴突途径。 在此提案中，我们计划研究由称为多极神经元的一大批耳蜗神经元所承载的轴突途径。我们提出，在声学信息处理的初始阶段，耳蜗核的腹侧分裂中的多极神经元起关键作用。 他们是人工耳蜗核的内在电路中的全部参与者，其轴突靶向听觉途径中的每个脑干核。多极神经元是一个异质种群，表明它们由细胞的几个不同的亚类组成。我们建议使用逆行途径追踪方法来识别多极神经元不同种群的靶标和电生理记录技术，以使每种类型的轴突途径与其生理反应特性相匹配。这些数据将提供有关大量耳蜗核细胞发挥的功能作用的新知识，并提供对中央听觉核中神经计算本质的见解。