DIRECTIONAL HEARING AND THE PRECEDENCE EFFECT

描述：本研究计划的长期目标是 了解听觉系统如何处理房间中的信息， 回声 实验将集中在描述优先效应， 声音之间感知和定位的竞争方面 来源及其回声。 拟议的研究将系统地探讨几个 知觉现象，涉及的优先和结果将是 在描述性优先模型的上下文中解释。 这些 研究将与P.I.平行进行。的工作神经 听觉脑干中的优先级相关。 目标1调查了 源（导联）和回波在房间中的相对位置的重要性 （滞后）。 这是一个重要的问题，因为优先权通常是假定的 在定向听力中发挥重要作用，然而，很少有经验 有数据支持这一假设。 目标2是验证使用 虚拟声学空间（VAS）刺激的优先研究，使所有 方向线索可以在严格的实验控制下， 操纵提供给这两个人的相对方向信息， 耳朵 目的3是测量自由视野中的优先性，并使用VAS刺激， 方位角平面（其中双耳视差线索主导定位） 以及在正中矢状面（其中光谱线索占主导地位 本地化）。 这些研究测试了关于 单声道和双耳机制调节优先的程度。 目标4 将优先级的调查扩展到多个回声范例，因此 使这些研究更接近现实环境， 包含一系列复杂的回声 到目前为止，关于这方面的研究很少。 主题已经完成。 这项工作可能有助于澄清为什么有听力的听众 有缺陷的人很难提取重要的信息， 混响和竞争的声音，并可能有助于开发助听器 旨在消除混响环境中的干扰。

DESCRIPTION: The long-term objective of this research program is to understand how the auditory system processes information in rooms with echoes. The experiments will focus on the precedence effect which describes aspects of competition for perception and localization between a sound source and its echoes. Proposed studies will systematically explore several perceptual phenomena that are involved in precedence and results will be interpreted in the context of a descriptive model of precedence. These studies will be conducted in parallel with the P.I.'s work on neural correlates of precedence in the auditory brainstem. Aim 1 investigates the importance of the relative locations in a room of the source (lead) and echo (lag). This is a significant question since precedence is generally assumed to play an important role in directional hearing, however, little empirical data are available to support this assumption. Aim 2 is to validate the use of virtual-acoustic-space (VAS) stimuli for precedence studies so that all directional cues can be brought under tight experimental control, allowing manipulation of the relative directional information provided to the two ears. Aim 3 is to measure precedence in free field and using VAS stimuli in the azimuthal plane (where binaural disparity cues dominate localization) and in the median-sagittal plane (where spectral cues dominate localization). These studies test fundamental hypotheses concerning the extent to which monaural and binaural mechanisms mediate precedence. Aim 4 extends investigations of precedence to a multiple-echo paradigm, thus bringing these studies closer to a realistic environment which normally contains a complex array of echoes. To date, very little research on this topic has been done. This work may help clarify why listeners with hearing impairments have difficulty extracting important information in the presence of reverberations and competing sounds, and may help develop hearing aids geared towards eliminating interference in reverberant environments.