FINE STRUCTURE OF 2F1-F2 ACOUSTIC DISTORTION PRODUCT

2F1-F2声失真积的精细结构

• 批准号: 2128146
• 负责人: NING-JI HE
• 金额: $ 3.43万
• 依托单位: MEDICAL UNIVERSITY OF SOUTH CAROLINA
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-05-01 至 1997-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2128146
• 关键词: cochlea; computer simulation; data collection; human subject; perceptual maskings; psychoacoustics; sound frequency

There is growing interest in the 2f1-f2 acoustic distortion product (ADP) for both clinical and research applications. It is highly frequency specific, it can be measured in majority of human and animal subjects, and it can be used objectively for the hearing screening of infants. However, the success of its application is limited by the fact that the generation mechanism for the ADP is still not fully understood. There are questions about the site of generation of the ADP, whether it is generated within a single cochlear region, or whether multiple regions contribute to the ADP measured in the ear canal. Detail about how the resultant ADP is generated within a specific region is also poorly understood. It is not clear whether the overall ADP results from essentially a single generator or from a group of generators continuously distributed within an area wherein contributions are vectorially summed. The study proposed here will investigate these issues with a new approach in which the fine frequency structure of the ADP and its basilar- membrane-related characteristics will be examined. With the aid of a vector sum model of ADP fine structure (Sun et al., I994a,b), four experiments will be conducted. The first two experiments are designed to examine the effects of the frequency and level ratios of the primary tones on the ADP fine structure. These first experiments will address basic issues concerning the site and number of ADP generators. For example, does re-emission from the 2f1-f2 place contribute to the resultant ADP fine structure? The latter two experiments will yield data concerning the effects of noise maskers on the ADP fine structure. Emphasis will be placed on the way the ADP fine structure is generated. Changes in the ADP fine structure with varying level and bandwidth of a narrowband masker will help determine if there is a vector sum mechanism involved in the generation of ADP fine structure, and if so, its critical bandwidth. These experiments will test the published model and will extend our basic knowledge of otacoustic emissions.

人们对 2f1-f2 声学失真积 (ADP) 越来越感兴趣 用于临床和研究应用。频率很高 具体来说，它可以在大多数人类和动物受试者中进行测量， 可客观用于婴儿听力筛查。 然而，其应用的成功受到以下事实的限制： ADP 的生成机制尚未完全清楚。有 关于ADP生成位点的问题，是否是 在单个耳蜗区域内生成，还是在多个区域内生成 有助于耳道中测量的 ADP。详细介绍如何 特定区域内产生的合成 ADP 也很差 明白了。目前尚不清楚总体 ADP 是否来自 本质上是单个发电机或连续的一组发电机 分布在一个区域内，其中贡献被矢量求和。 这里提出的研究将用一种新方法来调查这些问题 其中 ADP 的精细频率结构及其基底 将检查膜相关的特性。借助一个 ADP精细结构的向量和模型（Sun等人，I994a，b），四 将进行实验。前两个实验旨在 检查初级频率和电平比的影响 ADP 精细结构上的色调。这些第一个实验将解决 有关 ADP 发电机的地点和数量的基本问题。为了 例如，从 2f1-f2 位置重新发射是否有助于 所得ADP精细结构？后两个实验将产生数据 关于噪声掩蔽器对 ADP 精细结构的影响。 重点将放在 ADP 精细结构的生成方式上。 ADP精细结构随ADP水平和带宽的变化而变化 窄带掩蔽器将有助于确定是否存在矢量和机制 参与ADP精细结构的生成，如果是的话，它的关键 带宽。这些实验将测试已发布的模型，并将 扩展我们关于声发射的基本知识。