Effects of Sensorineural Hearing Loss on Robust Speech Coding

项目摘要 尽管最近的技术进步，人们仍然遭受通信困难，影响他们的生活。 职业，社会和家庭生活，以及他们的心理健康。听力损失患者 （SNHL）难以理解语音，特别是在嘈杂的情况下。事实上， 的临床定义的听力损失可以有广泛的语音识别能力，可能是由于差异 潜在的阈上缺陷，这是隐藏在目前的听力评估。虽然一个听众的 已知对同时进行频谱和时间调制（STM）的声音的敏感性可以预测 语音在噪声中的表现，这种预测能力的潜在机制仍然存在 一个积极辩论的话题。我们实验室和其他实验室的生理学证据表明，SNHL的几种形式 (e.g., OHC和/或IHC功能障碍）影响不同细胞中信号的通道内和跨通道调制编码。 的方式例如，由于OHC功能障碍而导致的扭曲的音调会影响内部的感知相关性。 调制域中的信道信噪比，以及 这些调制对源隔离有用。尽管这些明确和不同的影响调制 虽然信号编码的影响，这些影响是令人惊讶的研究不足，相对于信号在噪声编码，这是 拟议工作的重点。我们使用跨物种实验设计来收集解剖学上的、单一单位的 AN纤维、诱发反应和来自SNHL的几种临床前栗鼠模型的诊断数据，以及 诱发反应，诊断，心理物理和语音噪声数据，从人类听众跨越一个范围 年龄和听力状况目的1是表征SNHL对通道内调制掩蔽的影响， 其中收集的数据将测试OHC和IHC功能障碍各自降低感知的假设。 相关的神经调制信噪比，但在不同的方式。目的2是表征SNHL对 跨通道时间相干线索，其中收集的数据将测试扭曲的假设 音调映射在动物和人类听者中普遍存在，并且对周围听觉系统具有感知相关影响。 跨信道时间相干性。目的3是表征SNHL对STM灵敏度的影响，其中我们的交叉- 物种的数据将测试的假设，即短时记忆刺激的预测能力的语音在噪音的看法 主要来自于失真的音调和SNHL对时间调制编码的影响，而不是来自于 扩大的色调调整或降低的时间精度。数据将统一在一个开源数据库中- 科学框架，以促进我们和其他人未来的因果建模。我们独特的能力， 在严格感知相关框架内协同跨物种数据将使我们能够测试我们的一般 假设SNHL对噪声中信号的调制线索有几种不同的外围效应， 有助于噪音中言语感知的个体差异。从长远来看，这项工作将有助于个性化 通过提供知识，在现实世界意义的框架中对临床SNHL类别进行分层，从而改善听力学。

Project Summary Despite recent technological advances, people still suffer from communication difficulties that impact their professional, social, and family lives, as well as their mental health. People with sensorineural hearing loss (SNHL) struggle with understanding speech, particularly in noisy situations. In fact, people with similar degrees of clinically defined hearing loss can have a wide range of speech-recognition abilities, likely due to differences in underlying suprathreshold deficits that are hidden from current audiological assessment. Although a listener’s sensitivity to simultaneously spectrally and temporally modulated (STM) sounds is known to be predictive of speech-in-noise performance in individual listeners, the underlying mechanisms of this predictive power remain a topic of active debate. Physiological evidence from our lab and others demonstrate that several forms of SNHL (e.g., OHC and/or IHC dysfunction) affect within and across-channel modulation coding of signals in different ways. For example, distorted tonotopy due to OHC dysfunction can affect the perceptually relevant within- channel signal-to-noise ratio in the modulation domain, as well as across-channel temporal coherence of modulations that are useful for source segregation. Despite these clear and varied implications for modulation coding of signals, these effects are surprisingly understudied with respect to signal-in-noise coding, which is the focus of the proposed work. We use a cross-species experimental design to collect anatomical, single-unit AN-fiber, evoked-response, and diagnostic data from several pre-clinical chinchilla models of SNHL, as well as evoked-response, diagnostic, psychophysical, and speech-in-noise data from human listeners spanning a range of age and hearing status. Aim 1 is to characterize SNHL effects on within-channel modulation masking, where the data collected will test the hypothesis that OHC and IHC dysfunction each degrade the perceptually relevant neural modulation signal-to-noise ratio, but in distinct ways. Aim 2 is to characterize SNHL effects on across-channel temporal coherence cues, where the data collected will test the hypothesis that distorted tonotopy is prevalent in both animals and human listeners and has a perceptually relevant effect on peripheral across-channel temporal coherence. Aim 3 is to characterize SNHL effects on STM sensitivity, where our cross- species data will test the hypothesis that the predictive power of STM stimuli for speech-in-noise perception arises largely from distorted tonotopy and the effects of SNHL on temporal modulation coding, rather than from broadened tonotopic tuning or degraded temporal precision. Data will be harmonized in an open-source data- science framework to facilitate future causal modeling by us and others. Our unique ability to quantitatively synergize cross-species data within a rigorous perceptually relevant framework will allow us to test our general hypothesis that SNHL has several distinct peripheral effects on modulation cues for signals in noise, which contribute to individual differences in speech perception in noise. Long-term, this work will help to personalize audiology by providing knowledge to stratify the clinical SNHL category in a framework of real-world significance.