INFORMATION PROCESSING IN THE COCHLEAR NUCLEUS

本项目将研究耳蜗核的复杂信号处理 一系列平行和层次的听觉的第一步 发生信号处理事件。 不同的解剖细胞类型， 与不同的目标一起，形成平行路径和沿着的基底 丰富的核内电路网络塑造了 投射细胞 目前的目标是：使结构/功能 允许解剖细胞生理识别的相关性 类型，并探索这些类型如何处理复杂的声音，包括 振幅调制、N-谐波分量和语音刺激。 细胞外和细胞内记录将与 神经生物素标记，以建立五个结构-功能关系 目前尚不清楚的细胞群：（1） PVCN：哪些细胞组负责O/I和O/L模式， 它们与O/C细胞有什么关系？(2)类主反应PL， AVCN的PL/N和O/L均来自于丛状细胞，但它们之间存在差异。 它们之间的区别往往很难仅仅基于对音调的反应。 做 这些图案完全来自丛状细胞？(3)建立 AVCN中持续和瞬态斩波的形态学基础。（四） 确定发作分级应答模式、II型单位 DCN中的感受野和结核腹侧细胞是一个， 同一个小组(5)确定DCN中的侧手翻单元是否响应 到音调咔嗒声、AM、噪声、带凹口的噪声和/或对侧 声刺激 一项新的倡议将调查 神经生理反应的一组不同的语音，包括 在以前的神经生理学研究中没有使用过的声音。 检查大量的速度声音将有可能 将结果外推到言语感知。 心理物理 能力将被研究在龙猫作为一种行为辅助， 使用相同语音的神经反应研究 将在神经生理学研究中呈现。 在许多情况下， 对刺激对的神经反应，从一系列语音刺激中提取 从一个音素到另一个音素， 行为衍生的阈值将得到最深入的研究。 神经反应的信息理论计算分析将是 用于实现从神经编码到感觉能力的直接推理。

This project will study complex signal processing in the cochlear nucleus where the first steps of a cascade of parallel and hierarchical auditory signal processing events take place. Distinct anatomical cell types, each with different targets, form the substrate for parallel pathways and along with a rich network of intranuclear circuits shape the outputs of projecting cells. The present aims are: to make structure/function correlations that allow physiological identification of anatomical cell types and to explore how these types process complex sounds including amplitude modulation, N-harmonic component, and speech stimuli. Extracellular-and intracellular-recording will be combined with neurobiotin labeling to establish structure- function relations for five groups of cells that are not well understood: (1) Onset cells in the PVCN: What cells group(s) are responsible for O/I and O/L patterns and what is their relation to O/C cells? (2) The primary-like responses, PL, PL/N, and O/L, in the AVCN arise from bushy cells but distinguishing between them is often difficult based on responses to tones alone. Do these patterns arise from bushy-cells exclusively? (3) Establish the morphological basis for sustained and transient choppers in the AVCN. (4) Establish whether onset-graded response patterns, units with type II receptive fields and tuberculoventral cells in the DCN are one and the same cell group? (5) Establish whether cartwheel cells in the DCN respond to tones clicks, AM, noise, noise with notches, and/or contra-lateral acoustic stimulation. A new initiative will investigate neurophysiological responses to a diverse set of speech sounds including sounds that have not been used in previous neurophysiological studies. Examining a large array of speed sounds will make possible the extrapolation of results to speech perception. Psychophysical capabilities will be studied in the chinchilla as a behavioral adjunct to investigations of neural responses to speech using the same speech sounds that will be presented in the neurophysiological studies. In many cases, neural responses to stimulus pairs, drawn from series of speech stimuli varying from one phoneme to another, that bracket the animal's behaviorally derived thresholds will be most intensely studied. Information-theoretic computational analyses of neural responses will be used to enable direct inference from neural encoding to sensory capacity.