Origins of Binaural Processing in Vertebrates

描述（由申请人提供）：陆生动物使用双耳处理来帮助它们检测、区分、定位和隔离声源。中枢听觉系统的所有区域都参与用于这些一般听觉任务的计算，但哺乳动物和鸟类脑干的几个核在双耳处理方面得到了最深入的研究。最近对鱼类的观察，包括行为、中枢听觉系统形态学、外周和中枢神经生理学，都表明不仅信息从外周到表脑的流动在所有种类的有颚脊椎动物中遵循相同的一般模式，而且听觉本身在这些分类群中可能是同源的，最早是在早期鱼类中发展起来的。这反过来表明，双耳处理可能也首先在早期鱼类中发展起来。在本论文中，我们首次系统地研究了一种鱼（牡蛎蟾蜍鱼- Opsanus tau）双耳听力的策略和机制。这些研究结合了自然声学和双侧机械耳石操作，在体内，将提供鱼类双耳加工的第一个系统描述和分析，并将有助于确定在陆生动物中观察到的双耳机制是原始的，还是脊椎动物共有的，以及哪些机制可能是最近导出的。我们假设双耳加工的几个基本结构和功能方面是原始脊椎动物的特征，我们期望它们在鱼类的听觉脑干中得到原始的揭示。这项工作将有助于我们理解听觉系统和听觉的进化，从而有助于建立一个生物学和进化的背景，在这个背景下，人类听觉和人类听觉的动物模型可以更好地理解和应用。

DESCRIPTION (provided by applicant): Terrestrial animals use binaural processing to help them detect, discriminate, locate, and segregate sounds sources. All regions of the central auditory system participate in the computations used for these general tasks of hearing, but several nuclei of the mammalian and avian brainstem have been most intensively studied with respect to binaural processing. Recent observations on fishes, including behavior, central auditory system morphology and peripheral and central neurophysiology converge in suggesting not only that the flow of information from the periphery to the epencephalon follows the same general pattern in all classes of jawed vertebrates, but that the sense of hearing itself may be homologous within these taxa, having first developed among early fishes. This, in turn, suggests that binaural processing may have first developed in early fishes, too. In this proposal, we aim to systematically investigate, for the first time, the strategies and mechanisms of binaural hearing in a fish (oyster toadfish - Opsanus tau). These studies using combinations of natural acoustic and bilateral mechanical otolith manipulation, in vivo, will provide the first systematic description and analysis of binaural processing in a fish, and will help determine what binaural mechanisms observed in terrestrial animals are primitive, or shared among vertebrates, and what mechanisms are likely to have been more recently derived. We hypothesize that several fundamental structural and functional aspects of binaural processing are primitive vertebrate characters and we expect them to be primitively revealed in the auditory brainstem of fishes. This work will contribute to our understanding of the evolution of auditory systems and the sense of hearing, and thereby help establish a biological and evolutionary context within which human hearing and animal models for human hearing can be better understood and applied.