INTENSITY DLS AND MASKING IN NORMAL AND IMPAIRED HEARING

我们的长期目标是了解 听觉系统，将允许定量建模 对音调、噪音和语音的感知，在正常和 听力受损。这样的模式不仅将改善我们的 对正常听觉过程的理解，但也会 显著帮助为听力提供更好的诊断工具 听障人士的损害和更好的康复 听众。拟议的项目旨在获得一些迫切需要的 数据，并继续测试激励的一般概念 模式可以提供用于定量建模的框架 听力正常和受损。基于21，2AFC实验 正常监听者、受损监听者和具有 通过掩蔽正常耳朵来模拟损伤，建议的 该项目将为完善我们的 强度判别与测试的激励模式模型 与这个模型和其他模型相关的几个假设。我们的特定 目的是(1)检验两个假设，说明敏感性，d‘， 取决于两个声音之间的级别差异 通过心理测量函数的测量来区分 强度歧视，主要是在DLS较大的情况下。 (2)检验韦伯定律不成立的假设 单一听觉通道。强度作为能级意志的函数的DLS 对其激发受随机限制的声音进行测量- 水平掩蔽器包括少量的听觉通道。 (3)检验噪声中检测音调信号的假设 而强度歧视取决于类似的决策规则和 使用未加权(非最优)的信息总和 频道的最佳选择。检测和检测的测量 1 kHz音调和16音调复合体的强度辨别 将在固定条件下和在下列条件下进行 从试验到试验随机呈现两种类型的信号。 (4)开始扩展模型，以解释歧视 随着时间的推移而变化的声音。听觉的方式 系统可以使用励磁电平信息随着时间的推移 通过对强度的灵敏度d‘的测量进行评估 作为刺激持续时间的函数的辨别。(5) 假说是激发水平的信息比 听觉系统的适应过程所需的时间将是 在几个实验中进行了测试。用于多音调的强度DLS 脉冲串将作为脉冲串数量的函数进行测量 脉冲串间隔。在其他实验中，强度DLS 简短的音调将在前面的音调存在的情况下进行测量， 适应不同时长的语气。(六)进一步调查 时变声音的处理和决策的灵活性 进程，从掩蔽中释放出来的掩蔽--信封 波动将在几个实验中进行研究。这些 数据将显著增加我们对正常和 听觉处理能力受损，这对 开发和测试听觉系统的模型。

Our long-term objective is to reach an understanding of the auditory system that will allow quantitative modeling of the perception of tones, noise, and speech in both normal and impaired hearing. Such models not only will improve our understanding of normal auditory processes, but also will significantly aid in providing better diagnostic tools for hearing impairment and better rehabilitation of hearing-impaired listeners. The proposed project aims to obtain some sorely needed data and to continue testing the general concept that excitation patterns may provide a framework for quantitative modeling of normal and impaired hearing. Based on 21, 2AFC experiments in normal listeners, impaired listeners, and listeners with impairments simulated by masking a normal ear, the proposed project will establish a firm psychoacoustic basis for refining our excitation-pattern model of intensity discrimination and testing several hypotheses related to this and other models. Our specific aims are (1) To test two hypotheses stating how sensitivity, d', depends on the level difference between two sounds being discriminated by measurements of psychometric functions for intensity discrimination, primarily in conditions with large DLs. (2) To test the hypothesis that Weber's Law does not hold within a single auditory channel. Intensity DLs as a function of level will be measured for sounds whose excitation is limited by random- level maskers to comprise a small number of auditory channels. (3) To test the hypothesis that detection of tonal signals in noise and intensity discrimination depends on similar decision rules and employ an unweighted (non-optimal) sum of information from an optimum selection of channels. Measurements of detection and intensity discrimination of a 1-kHz tone and a 16-tone complex will be made in fixed conditions and in conditions in which these two types of signals are presented at random from trail to trial. (4) To begin extending the model to account for discrimination of sounds that vary over time. The manner in which the auditory system can use excitation-level information over time will be assessed through measurements of sensitivity, d', for intensity discrimination as a function of stimulus duration. (5) The hypothesis is that excitation-level information decreases over time due to adaptation processes in the auditory system will be tested in several experiments. Intensity DLs for multiple tone bursts will be measured as function of number of the bursts and the inter-burst interval. In other experiments, intensity DLs for brief tones will be measured in the presence of a preceding, adapting tone of various durations. (6) To further investigate the processing of time-varying sounds and the flexibility of decision processes, the release from masking caused by masker--envelope fluctuations will be investigated in several experiments. These data will significantly add to our knowledge of normal and impaired auditory processing and will be important for the development and testing of models of the auditory system.