Masking release in hearing loss: cochlear compression and effective audibility

听力损失中的掩蔽释放：耳蜗压缩和有效听觉

• 批准号: 7595121
• 负责人: Peggy B Nelson
• 金额: $ 36.32万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-01 至 2013-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7595121
• 关键词: Access to Information; Accounting; Affect; Algorithms; Auditory; Basilar Membrane; Cochlear Hearing Loss; Companions; Devices; Elderly; Environment; Frequencies; Future; Hearing; Hearing Aids; Lead; Life; Masks; Measures; Methods; Modeling; Nature; Noise; Output; Pattern; Performance; Peripheral; Physiology; Play; Process; Psychoacoustics; Psychophysiology; Recovery; Reliance; Research; Residual state; Resolution; Role; Sensorineural Hearing Loss; Signal Transduction; Simulate; Source; Speech; Speech Intelligibility; System; Test Result; Testing; Time; base; computerized data processing; design; experience; hearing impairment; improved; indexing; models and simulation; public health relevance; remediation; research study; response; sound; speech recognition

DESCRIPTION (provided by applicant): Listeners with sensorineural hearing loss experience significantly more masking and significantly less release from masking than do listeners with normal hearing sensitivity. When background noise is intermittent, normal- hearing (NH) listeners take advantage of the momentary dips in the noise to understand the target signal. This benefit is termed masking release (MR). Hearing-impaired (HI) listeners do not experience the same degree of MR as NH listeners. As a result, HI listeners cannot understand speech in noisy environments at the same signal-to-noise ratios in which NH listeners can understand successfully. At the same time, listeners with hearing loss frequently complain that their amplification devices are not satisfactory in background noise. We propose to further our understanding of the masking and MR experienced by listeners with hearing loss and to investigate the causes and potential sources of remediation. In Experiment 1 we will test MR in speech recognition experiments across a wide range of noise and signal levels and bandwidths. We will test NH and HI listeners, as well as NH listeners whose thresholds will be elevated by noise to match those of the HI listeners. We will measure listeners' sentence recognition in quiet, steady noise, and fluctuating noise and will define MR as the performance difference between steady and fluctuating noise. We hypothesize based on preliminary results that signal audibility will not fully explain the reduced MR of HI listeners, and that additional variability is explained by HI listeners' reduced access to spectrotemporal information about the speech in the dips of noise. We further hypothesize that underlying changes in cochlear physiology can explain HI listeners' difficulty in conditions of intermittent noise, and we propose to measure cochlear function in Experiment 2. We will measure basilar membrane input/output responses, masking period patterns, modulation masking, and frequency selectivity to describe HI listeners' cochlear function. We will use results from Experiment 2 to compute the adjusted effective audibility experienced by HI listeners taking into account the loss of cochlear gain experienced by HI listeners. In Section 3 we will model and simulate the effects of cochlear hearing loss based on speech recognition and psychoacoustic test results obtained from the same listeners. We hypothesize that these models and simulations will provide accurate and useful predictions of MR in young HI listeners. We will use the resulting models and simulations as empirically based first steps in evaluating signal processing for noise reduction. In later years the models can also be applied further to listeners with severe hearing loss, and to elderly listeners with hearing loss. Overall, the findings will contribute to our understanding of the nature of hearing loss, the effects of reduced audibility and cochlear gain, and the implications for understanding speech in a variety of noise backgrounds. We hypothesize that improving our understanding of the nature of reduced masking release will improve our ability to develop signal processing algorithms that can more effectively remediate HI listeners' difficulties in noise. PUBLIC HEALTH RELEVANCE Results from the proposed experiments and models will help understand hearing-impaired listeners' difficulty understanding speech in background noise. We anticipate that models developed in this project will lay the groundwork for evaluating signal-processing algorithms to maximize speech intelligibility in noise.

描述（由申请人提供）：与听力正常的听者相比，感觉神经性听力损失的听者经历的掩蔽明显更多，从掩蔽中释放的明显更少。当背景噪声是间歇性的，正常听力（NH）听者利用噪声的瞬间下降来理解目标信号。这种益处被称为掩蔽释放（MR）。听力受损（HI）的听众不像听力受损的听众那样经历同样程度的MR。因此，HI听者无法在嘈杂的环境中以与NH听者相同的信噪比理解语音。与此同时，听力损失的听众经常抱怨他们的扩音设备在背景噪音下效果不佳。我们建议进一步了解听力损失听众所经历的掩蔽和MR，并调查原因和潜在的补救来源。在实验1中，我们将在广泛的噪声和信号水平和带宽范围内的语音识别实验中测试MR。我们将测试NH和HI侦听器，以及NH侦听器，其阈值将被噪声提高以匹配HI侦听器的阈值。我们将测量听者在安静噪声、稳定噪声和波动噪声下的句子识别能力，并将MR定义为稳定噪声和波动噪声之间的表现差异。根据初步结果，我们假设信号可听性并不能完全解释HI听者MR的降低，而额外的可变性可以解释为HI听者在噪音下降时获取语音光谱时间信息的减少。我们进一步假设耳蜗生理学的潜在变化可以解释HI听者在间歇性噪声条件下的困难，我们建议在实验2中测量耳蜗功能。我们将测量基底膜输入/输出响应、掩蔽周期模式、调制掩蔽和频率选择性来描述HI听众的耳蜗功能。我们将使用实验2的结果来计算HI听者在考虑耳蜗增益损失的情况下所经历的调整后的有效可听性。在第3节中，我们将基于同一听者的语音识别和心理声学测试结果，对耳蜗听力损失的影响进行建模和模拟。我们假设这些模型和模拟将为年轻HI听众提供准确和有用的MR预测。我们将使用得到的模型和模拟作为基于经验的第一步来评估信号处理降噪。在以后的几年里，这些模型还可以进一步应用于听力损失严重的听众，以及听力损失的老年听众。总的来说，这些发现将有助于我们理解听力损失的本质，可听性降低和耳蜗增益的影响，以及在各种噪音背景下理解语言的含义。我们假设，提高我们对减少掩蔽释放本质的理解将提高我们开发信号处理算法的能力，这些算法可以更有效地纠正HI听众在噪声中的困难。本文所提出的实验和模型的结果将有助于理解听障听众在背景噪声中理解言语的困难。我们预计本项目中开发的模型将为评估信号处理算法奠定基础，以最大限度地提高噪声中的语音清晰度。