Speech Perception Impairments in Healthy Normal-Hearing Adults: Neural Mechanisms

描述(由申请人提供)：本项目的目标是开发用于研究听力正常和没有发育障碍的健康年轻人的言语感知障碍的测量方法，并获得一个个体差异测量的数据库，以分析与实验测量的关系。有言语感知障碍的健康成年人可能会在听力学诊所抱怨在听力状况恶化的情况下难以感知言语，但经检查后发现他们的听力正常。但噪音中的语音测试证实了他们的抱怨。然后可以考虑将它们用于临床诊断中枢听觉处理障碍(CAPD)，但对于如何诊断CAPD没有一致意见；CAPD没有标准测试；甚至尚不清楚其原因是否为听觉处理障碍。目前还没有证实有神经基础。认知神经科学为研究其他健康年轻人言语知觉障碍(SPI)的神经基础提供了一个框架。我们假设那些抱怨言语感知困难的个体存在于个体差异的连续体中。我们假设，负责SPI的神经机制可能是单独出现的，也可能是在刺激表征、注意力和工作记忆水平上的交互作用。一个 延迟再认记忆范式将被用来研究这些机制。该范式旨在获得对语音做出反应的行为和电生理(EEG)测量。听力正常、有SPI的健康成年人将被招募进行研究，并与年龄相近的没有言语感知障碍的正常成年人进行比较。所有参与者都将接受一系列的听力测试和其他筛选，包括言语智力、精神状态和语音工作记忆的测试。然后，他们将在建议的延迟识别记忆范式中进行测试，以获得与工作记忆、注意力和语音刺激编码相关的行为和脑电结果。刺激将是无意义的音节或真实的单词，要么是自然录音，要么是声码。将使用脑电、行为和临床测量进行广泛的个体差异和群体统计分析。将在正常组和SPI组中寻找个体差异分数，并将其作为组成员的可靠预测指标。随着对导致不同群体和个人语音感知差异的神经机制有了更好的了解，临床评估可以变得更准确，治疗方法也可以开发出来。我们设想推进这一项目，为成人和儿童开发临床测试。

DESCRIPTION (provided by applicant): The goals of this project are to develop measures for studying speech perception impairments in healthy younger adults with normal hearing and without developmental disorders and to obtain a database of individual differences measures to analyze in relationship to experimental measures. Healthy adults with speech perception impairments may present at an audiology clinic complaining of difficulty perceiving speech under degraded listening conditions, yet upon examination they are found to be audiologically normal. But speech-in- noise testing confirms their complaint. They may then be considered for a clinical diagnosis of central auditory processing disorder (CAPD), but there is not agreement as to how to diagnosis CAPD; there are no standard tests of CAPD; and unknown even is whether its cause is a disorder of auditory processing. No neural bases have been confirmed. Cognitive neuroscience offers a framework for investigating the neural bases for speech perception impairment (SPI) in otherwise healthy young adults. We hypothesize those individuals who complain of speech perception difficulties exist on a continuum of individual differences. We hypothesize that the neural mechanisms responsible for the SPI could arise singly or in interaction at the levels of stimulus representation, attention, and working memory. A delayed recognition memory paradigm will be developed to investigate these mechanisms. The paradigm is designed to obtain behavioral and electrophysiological (EEG) measures in response to speech. Healthy adults with normal hearing and with SPI will be recruited for study and compared to similar age normal adults without speech perception impairments. All participants will undergo a battery of audiological tests and other screening, including tests for verbal intelligence, mental status, and phonological working memory. Then they will be tested in the proposed delayed recognition memory paradigm to gain behavioral and EEG results related to working memory, attention, and speech stimulus encoding. Stimuli will be nonsense syllables or real words that are either natural recordings or vocoded. Extensive individual differences and group statistical analyses will be carried out using the EEG, behavioral, and clinical measures. Individual differences scores will be sought across normal and SPI groups and as reliable predictors of group membership. With better understanding of neural mechanisms responsible for differences in speech perception across groups and individuals, clinical evaluations can become more accurate and treatments can be developed. We envision carrying this project forward to develop clinical tests for adults and also children.