Sound localization and selective auditory attention

描述（由申请人提供）：本项目的总体目标是了解声音定位和选择性听觉注意的神经机制。这些结果将有助于理解大脑如何整合来自两只耳朵的听觉信息，以及它如何在嘈杂的环境中将注意力集中在一个来源上。这种电路在我们在背景噪音存在下检测信号的能力中起着重要作用，这是老年人听力损失的主要症状。了解神经机制将有助于助听器的设计和治疗。 有两个主要目标。首先，我们将使用两个著名的空间听觉错觉来研究空间声源在下丘的表征。实验将在清醒和受过训练的猫中使用结合的行为和生理准备。我们将继续我们正在进行的关于优先效应的心理物理学和生理学实验，并开始一系列关于弗朗森效应的新实验。这两种错觉都是强烈的听觉错觉，可以在我们的行为准备中很容易地得到证明。其次，我们将发展一个新的心理物理学范式来研究选择性听觉注意。将训练猫注意一侧的扬声器，以便进行频率辨别，同时忽略来自对侧的声音。我们假设，与没有提示动物注意一侧或另一侧的试验相比，注意一侧将增强执行辨别的能力。然后，我们将使用创新的硅胶多通道探针从听觉皮层进行生理记录，以寻找在这项任务中注意力的调制。 空间听觉和选择性注意是听觉系统的重要基本功能：人类患者的双耳功能缺陷可能导致在嘈杂的房间中理解对话的相当大的困难，这是听力受损者最常见的抱怨，并可能导致严重的社交退缩。

DESCRIPTION (provided by applicant): The overall aim of this project is to understand the neural mechanisms of sound localization and selective auditory attention. These results will help to understand how the brain integrates auditory information from the two ears and how it can direct attention to one source over others in a noisy environment. This circuitry plays a major role in our ability to detect signals in the presence of background noise, which is the major symptom of elderly people with hearing loss. Understanding the neural mechanisms will help in the design of hearing aids and therapy. There are two major aims. First, we will use two well-known spatial auditory illusions to study the representation of sound sources in space in the inferior colliculus. Experiments will use a combined behavioral and physiological preparation in awake and trained cats. We will continue our on-going experiments on the psychophysics and physiology of the precedence effect and begin a new series of experiments on the Franssen effect. Both of these are robust auditory illusions that can be readily demonstrated in our behaving preparation. Second, we will develop a new psychophysical paradigm for studying selective auditory attention. Cats will be trained to attend to a speaker on one side in order to make frequency discriminations while ignoring sounds from the contralateral side. We hypothesize that attending to one side will enhance the ability to perform the discrimination as compared to trials in which the animal is not cued to attend to one side or the other. We will then make physiological recordings from the auditory cortex using an innovative silicone multichannel probe to look for modulation by attention during this task. Spatial hearing and selective attention are important basic functions of the auditory system: defects in binaural function in human patients can lead to considerable difficulty in understanding conversations in a noisy room, which is the most common complaint of the hearing-impaired and can lead to severe social withdrawal.