Asynchronous glimpsing of speech in the hearing impaired

描述（由申请人提供）：本项目的长期目标是研究频率分辨率降低对听障听众在复杂噪声环境下语音感知的影响。该项目的具体目标是通过心理物理和计算来评估在时间和频率波动的掩蔽物存在下的语音接收情况，就像自然发生的声音一样。本实验旨在比较听力受损者和听力正常者在一项任务上的表现，该任务已被证明可以突出掩蔽传播（SM）的影响。通过将交替刺激带分离到对耳，从而消除SM对相邻频带的影响，正常听力听者的初始数据显示屏蔽释放约为5至8 dB。目的1将测试正常听力和听力受损的听众在存在异步调制噪声时的辅音识别。该研究将验证以下主要假设：短信减少了听力受损听众的可用视觉机会，以及相对于听力正常的听众，取消短信能提高他们的表现。Aim 2将在与Aim 1相同的条件下测试辅音识别，对听力正常的听众进行模拟听力损失测试。这项研究将检验最初的假设，即听力下降本身并不能解释听力受损听众的双重听力好处，而是降低的频率分辨率是消除SM的好处的原因。目标3将使用改进的瞥见模型对行为数据进行计算建模。该研究将测试频谱分辨率在正常听力和听力受损听众的异步瞥见中起关键作用的假设；通过分析二分呈现的刺激，该模型有望预测在行为数据中看到的益处。研究结果将有助于更好地理解听力受损的听者在复杂背景下跟随言语能力下降的原因，并对未来的听觉假体设计产生影响。当前提案中概述的培训计划为研究设计提供了强有力的指导，特别是在信号处理，数据分析和计算建模方面。

DESCRIPTION (provided by applicant): The long-term aim of this project is to investigate the role of reduced frequency resolution on speech perception in complex noise for hearing-impaired listeners. The specific objective of the proposed project is to psychophysically and computationally assess speech reception in the presence of a masker that fluctuates both in time and frequency, like naturally occurring sounds. The proposed experiments are designed to compare hearing-impaired and normal-hearing listeners on a task which has been shown to highlight the effect of spread of masking (SM). By separating alternating stimulus bands to opposite ears, thus removing the effect of SM from neighboring frequency bands, initial data in normal-hearing listeners show release from masking on the order of 5 to 8 dB. Aim 1 will test normal-hearing and hearing-impaired listeners on consonant recognition in the presence of an asynchronously modulated noise. The study will test the primary hypotheses that SM reduces available glimpsing opportunities for hearing-impaired listeners, and that removing SM enhances performance relative to normal-hearing listeners. Aim 2 will test consonant recognition in the same conditions as Aim 1, testing normal-hearing listeners with simulated hearing-losses. The study will test the primary hypothesis that reduced audibility alone cannot explain the dichotic listening benefit in hearing-impaired listeners, but rather that reduced frequency resolution is responsible for the benefit of removing SM. Aim 3 will computationally model the behavioral data using a modified glimpsing model. The study will test the hypotheses that spectral resolution plays a key role in asynchronous glimpsing for both normal-hearing and hearing-impaired listeners; by analyzing dichotically presented stimuli, the model is expected to predict the benefit seen in the behavioral data. Results will contribute to a better understanding of factors responsible for hearing-impaired listeners' reduced ability to follow speech in complex backgrounds, with implications for the future of auditory prosthesis design. The training program outlined in the current proposal provides strong mentorship in research design, especially with regard to signal processing, data analysis, and computational modeling. PUBLIC HEALTH RELEVANCE: The proposed work is relevant to the public health in that it investigates the effects of sensorineural hearing loss on the ability to process speech in the presence of competing noise. Speech testing and modeling approaches will be used to determine whether negative effects of background noise in hearing-impaired patients can be ameliorated using stimulus techniques that distribute sounds between the two ears. The results will advance our understanding of hearing-impairment and the potential for benefit via stimulus processing.