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

描述（由申请人提供）：本项目的目标是制定研究听力正常且无发育障碍的健康年轻人的言语感知障碍的措施，并获得个体差异措施数据库，以分析与实验措施的关系。患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退化的听力条件下难以感知言语，但在检查后发现他们听力正常。但噪音测试证实了他们的抱怨。然后，他们可能会被认为是一个临床诊断的中央听觉处理障碍（CAPD），但有没有协议，以如何诊断CAPD;有没有CAPD的标准测试;甚至是未知的原因是否是一个障碍的听觉处理。神经基础还没有被证实。认知神经科学提供了一个框架，调查的神经基础，言语知觉障碍（SPI），否则健康的年轻人。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上。我们假设，负责SPI的神经机制可能会出现单独或在刺激表征，注意和工作记忆的水平上的相互作用。一 延迟再认记忆范式将被用来研究这些机制。该范例的目的是获得行为和电生理（EEG）的措施，以响应语音。将招募听力正常且患有SPI的健康成人进行研究，并与年龄相似且无言语感知障碍的正常成人进行比较。所有参与者都将接受一系列听力测试和其他筛查，包括语言智力、精神状态和语音工作记忆测试。然后，他们将在拟议的延迟识别记忆范式进行测试，以获得与工作记忆，注意力和言语刺激编码相关的行为和EEG结果。刺激将是无意义的音节或真实的单词，这些单词是自然记录或语音编码的。将使用EEG、行为和临床测量进行广泛的个体差异和组统计分析。将在正常和SPI组中寻找个体差异评分，并将其作为组成员资格的可靠预测因子。随着对不同群体和个体之间言语感知差异的神经机制的更好理解，临床评估可以变得更加准确，治疗方法也可以得到发展。我们设想将该项目向前推进，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.