Effects of Sensorineural Hearing Loss on Robust Speech Coding

项目摘要 尽管最近的技术进步，人们仍然遭受沟通困难，影响他们的 职业、社交和家庭生活，以及他们的心理健康。感音神经性耳聋患者 (SNHL)很难理解语音，特别是在嘈杂的情况下。事实上，拥有相似学位的人 临床定义的听力损失可能具有广泛的语音识别能力，这可能是由于差异 在潜在的阈值上的缺陷，对目前的听力学评估是隐藏的。尽管听众的 已知对同时频谱和时间调制(STM)的声音的敏感性可以预测 在单个听众的噪声中讲话的表现，这种预测能力的潜在机制仍然 一个激烈辩论的话题。来自我们实验室和其他实验室的生理证据表明，几种形式的SNHL (例如，OHC和/或IHC功能障碍)影响不同的信号的信道内和跨信道调制编码 方式。例如，由于OHC功能障碍而导致的扭曲的音调可能会影响到- 调制域中的信道信噪比以及信道间的时间相干 对源分离有用的调制。尽管对调制的这些明确和不同的含义 对于信号的编码，令人惊讶的是，相对于噪声中信号编码，这些影响被研究得不够，这是 拟议工作的重点。我们使用跨物种的实验设计来收集解剖的、单单元的 来自几个临床前的栗鼠SNHL模型的AN纤维、诱发反应和诊断数据，以及 来自人类听众的诱发反应、诊断、心理物理和噪声中的语音数据 年龄和听力状况。目标1是表征信道内调制掩蔽上的SNHL效应， 收集的数据将检验OHC和IHC功能障碍各自降低知觉的假设 相关的神经调制信噪比，但方式不同。目标2是表征SNHL对 跨海峡时间一致性提示，其中收集的数据将测试扭曲的假设 声调复制在动物和人类听众中都很普遍，并对外周有知觉上的相关影响 跨海峡时间相干性。目标3是表征SNHL对STM敏感性的影响，其中我们的交叉- 物种数据将检验STM刺激对噪声中语音感知的预测能力这一假设 主要是由于扭曲的音调和SNHL对时间调制编码的影响，而不是来自 色调调谐范围扩大或时间精度降低。数据将在开源数据中得到协调- 科学框架，以促进我们和其他人未来的因果建模。我们独一无二的量化能力 在严格的感知相关框架内协同处理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信号具有几种不同的外围效应，这 在噪音中造成语音感知的个体差异。从长远来看，这项工作将有助于个性化 听力学通过提供知识，在现实世界意义的框架内对临床SNHL类别进行分层。

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.