Sound Source Segregation and Determination

描述（由申请人提供）：人类听觉的最重要特征是那些以导致确定实际声源的方式促进声学特征的分离和整合的特征。由于环境通常包括多个和同时的对象，听觉系统必须从根本上起“分离机”的作用，其工作是从到达耳朵的源声音的复杂混合物中确定单个源。这种听觉场景分析现在被认为是人类听觉的一个重要功能。我们认为，这些功能也是一般脊椎动物听觉的原始特征，这些功能在脊椎动物听觉系统的进化过程中最重要的是定义了成功和适应性。总体目标是确定这些脊椎动物听觉的原始功能如何在相对简单的脊椎动物物种中运作。一个目标是帮助建立一个生物和进化的背景下，人类的听力可以更充分地理解。目标1：我们将研究一个简单的脊椎动物物种的能力，以确定源特性时，有多个，同时存在的声源（即，听觉场景分析和源分离）。我们将研究其他声学特征，促进听觉感知分离在人类听众对鱼类听众的影响。这些特征包括起始频率、振幅调制、持续时间、谐波结构（以及空间原点：Aim 2）。这些功能将被调查的感知使用行为条件反射方法，刺激泛化范式的影响。目标2：我们将使用多个离散的本地源来研究听觉源分离。我们将独立于非空间声学特征（目标1），可能发挥作用的声源seseglation的空间来源的影响进行分析。目标3：我们将通过记录外周和中枢听觉神经元对上述行为实验中使用的相同信号和源的反应，来确定源分离背后的神经代码和表征的性质。我们将重点了解大脑可用于分离和整合来自一个或多个来源的同步声学分量的神经活动维度。

DESCRIPTION (provided by applicant): The most important features of the human sense of hearing are those that promote the segregation and integration of acoustic features in a way that results in the determination of actual sound sources. Since environments often include multiple and simultaneous objects, the auditory system must function fundamentally as a "separation machine" whose job it is to determine individual sources from the complex mixture of source sounds reaching the ears. This sort of auditory scene analysis is now well appreciated as an important function of human hearing. We suggest here that these functions are also primitive features of a general vertebrate sense of hearing, and that these are the functions that have defined success and fitness most importantly throughout the evolution of the vertebrate auditory system. The overall goals are to determine how these primitive functions of the vertebrate sense of hearing operate in a relatively simple vertebrate species. One goal is to help establish a biological and evolutionary context within which human hearing can be more fully understood. Aim 1: We will investigate the capacities of a simple vertebrate species to determine source characteristics when there are multiple, simultaneous sound sources present (i.e., auditory scene analysis and source segregation). We will investigate other acoustic features that promote auditory perceptual segregation in human listeners for their effects on fish listeners. These features include onset asynchrony, amplitude modulation, duration, harmonic structure, (and spatial origin: Aim 2). These features will be investigated for their effects on perception using behavioral conditioning methods using stimulus generalization paradigms. Aim 2: We will investigate auditory source segregation using multiple, discrete local sources. We will analyze the effects of the spatial origin of sources independently of the non-spatial acoustic features (Aim 1) that may play a role in sound source sesegregation. Aim 3: We will determine the nature of the neural codes and representations underlying source segregation by recording from peripheral and central auditory neurons in response to the same signals and sources used in the above behavioral experiments. We will focus on understanding the dimensions of neural activity that the brain could use in segregating and integrating simultaneous acoustic components from one or more sources.