Asynchronous glimpsing of speech in the hearing impaired

描述(申请人提供)：本项目的长期目标是调查降低的频率分辨率在复杂噪声中对听力受损听者的言语感知的作用。拟议项目的具体目标是在掩蔽者在场的情况下，对语音接收进行心理物理和计算评估，掩蔽者在时间和频率上都会波动，比如自然产生的声音。这项拟议的实验旨在比较听力受损和听力正常的听者在一项任务中的表现，这项任务已被证明突出了掩蔽扩散(SM)的影响。通过将交替的刺激频段分离到对侧耳朵，从而消除SM对相邻频段的影响，正常听力听者的初始数据显示出从掩蔽中释放的5到8分贝的数量级。目标1将测试听力正常和听力受损的听众在存在异步调制噪声的情况下识别辅音的能力。这项研究将检验主要的假设，即SM减少了听力受损的听者可获得的瞥见机会，并且与听力正常的听者相比，去除SM可以提高性能。目标2将在与目标1相同的条件下测试辅音识别，测试听力正常的听众，并模拟听力损失。这项研究将检验最初的假设，即仅靠降低可听度不能解释听力受损的人的双耳听力益处，而是频率分辨率降低是消除SM的好处的原因。Aim 3将使用改进的掠过模型对行为数据进行计算建模。这项研究将检验以下假设：光谱分辨率在听力正常和听力受损的听众的非同步一瞥中扮演着关键角色；通过分析两种呈现的刺激，该模型有望预测行为数据中看到的好处。研究结果将有助于更好地理解导致听力受损的听者在复杂背景下跟随语言的能力下降的因素，并对未来的听觉假体设计产生影响。目前提案中概述的培训方案在研究设计方面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.