SOUND SOURCE LOCALIZATION AND IDENTIFICATION BY A MODEL AUDITORY SYSTEM

我们的总体目标是确定一个简单的脊椎动物听觉系统 在听觉的基本过程中起作用：检测， 识别、分类和声源位置。期间 在上一个资助期，我们证明了金鱼（Carassius auratus） 表现得好像他们有内部感知维度， 光谱音高、虚拟音高、音色和粗糙度。此外，本发明还提供了一种方法， 生理实验表明，简单的离散通道 外围的频率选择性在所述频率选择性被改变时或之前被改变， 中脑的水平进入更敏锐的调谐和连续分布 滤波器组阵列，已通过抑制合成。抑制作用 中脑还合成了新的定向反应模式。 这些和其他结果导致了这样一种假设，即生理上的 哺乳动物的听觉系统和听觉的功能， 心理声学研究表明，哺乳动物是原始的脊椎动物 鱼类和其他非哺乳动物共有的特征。在同一 鱼类代表了脊椎动物中的一个极端地位， 内耳结构和外周表征 频率.因此，了解鱼类的听力机制是一个 进一步评估变异程度的重要基准 和脊椎动物之间的相似性作为一个群体，并建立一个 在生物学背景下，人类的听觉可以更完整地 明白该项目侧重于两个基本方面， 脊椎动物的听觉：处理光谱和时间 复杂的声音唤起对音高的感知， 声源定位的机制。互补的行为， 神经生理学和建模研究提出将有助于确定 神经结构，代码和机制，这些基本的 脊椎动物听觉的各个方面。

Our overall goals are to determine how a simple vertebrate auditory system functions in the fundamental processes of hearing: the detection, identification, classification, and the location of sound sources. During the last grant period we demonstrated that goldfish (Carassius auratus) behave as if they had internal perceptual dimensions corresponding to spectral pitch, virtual pitch, timbre, and roughness. In addition, physiological experiments have revealed that the simple, discrete-channel frequency selectivity of the periphery is transformed at or prior to the level of the midbrain into more sharply-tuned and continuously distributed filterbank array that has been synthesized by inhibition. Inhibition in the midbrain has also synthesized novel directional response patterns. These and other results have led to the hypothesis that the physiological functions of the mammalian auditory system and the sense of hearing among mammals as revealed in psychoacoustical studies are primitive vertebrate characters shared by fishes and other non-mammalian taxa. At the same time, fishes represent an extreme position among vertebrates with respect to phylogeny, inner ear structure, and peripheral representations of frequency. Understanding the mechanisms of hearing among fishes is thus an important bench-mark for further evaluating the dimensions of variation and similarity among vertebrates as a group, and for establishing a biological context within which human hearing can be more completely understood. This project focuses on two fundamental aspects of the vertebrate sense of hearing: the processing to spectrally and temporally complex sounds evoking perceptions of pitch, and the abilities and mechanisms for sound source localizations. The complementary behavioral, neurophysiological, and modeling studies proposed will help identify the neural structures, codes, and mechanisms underlying these fundamental aspects of vertebrate hearing.