AUDITORY-VISUAL INTEGRATION AND AGE

描述（由申请人提供）：日常对话通常包括看到和听到我们的沟通伙伴，这是老年人与家人和社区保持联系的重要手段。我们之前的研究对衰老如何影响唇读能力和口语理解的基础知识做出了贡献。在这个资助周期中，我们将试图解释为什么有些人在以视听方式呈现谈话者的演讲时，比他们仅凭视觉和听觉的表现所预测的要多得多。基于这些知识，我们的目标是开发干预措施，以提高老年人的口语理解能力。提出的研究是由一个视听整合模型驱动的，该模型考虑了大多数现有模型中没有纳入的信号和词汇因素。重要的是，我们将使用一个描述部分听觉和视觉信息总和的方程来消除视听整合和单模态单词识别能力的混淆。为了完成我们的第一个具体目标，我们将操纵听觉和视觉语音信号的特性，以定位日常口语理解中与年龄相关的差异的来源。我们已经开发了矩阵式的单词识别测试，这将使我们能够确定处理速度和工作记忆的年龄差异如何影响音素和视素激活水平上的AV整合。对于我们的第二个特定目标，我们开发了两个新的开放集单词测试，一个系统地改变激活的候选单词的数量，另一个系统地改变单词的频率。通过这些测试，我们将操纵影响不同词的感知混淆性的词汇特性，并确定认知因素如何与竞争词候选的激活水平相关。在我们最后的具体目标中，我们将使用我们实验室开发的视听口语理解测试，以确定可以预测年龄和个体差异的变量，这些变量可以从慢速说话中获益。我们的目标是确定慢速语言如何能最好地提高老年人对扩展的口语段落的理解，并预测谁将从这种干预中受益最大。实现这些目标将具有理论和临床意义，使我们能够评估视听语音处理的理论模型，并测试提高老年人口语理解能力的方法。总的来说，这个项目代表了一个独特的机会，它汇集了听觉康复专家、认知心理学家和临床研究听力学家，目的是为老年人开发听觉康复程序，该程序基于一个经过良好测试的理论模型，并理解认知测量与视听语言理解的关系。

DESCRIPTION (provided by applicant): Everyday conversation typically involves both seeing and hearing our communication partners, and affords a vital means by which older adults stay engaged with their families and communities. Our previous research has contributed to fundamental knowledge of how aging affects both lipreading ability and spoken language comprehension. In this grant cycle, we will seek to explain why some individuals recognize much more of a talker's speech when it is presented audiovisually than would be predicted based on their vision-only and auditory-only performance, and based on this knowledge, we aim to develop interventions to enhance older adults' spoken language comprehension. The proposed studies are motivated by a model of audiovisual integration that takes into account both signal and lexical factors that are not incorporated into most existing models. Importantly, we will use an equation describing the summation of partial auditory and visual information to unconfound audiovisual integration and unimodal word recognition abilities. In order to accomplish our first Specific Aim, we will manipulate the properties of auditory and visual speech signals in order to localize the sources of age-related differences in everyday spoken language comprehension. We have developed matrix-style word recognition tests that will allow us to determine how age differences in processing speed and working memory affect AV integration at the level of phoneme and viseme activation. For our second Specific Aim, we have developed two new open-set word tests, one that systematically varies the number of activated word candidates and another that systematically varies word frequency. Using these tests, we will manipulate lexical properties affecting the perceptual confusability of different words and determine how cognitive factors relate to the activation levels of competing word candidates. For our final Specific Aim, we will use a test of audiovisual spoken language comprehension developed in our laboratory in our effort to identify variables that can predict age and individual differences in the benefits from slower speech. Our goal is to determine how slowed speech can best enhance older adults' comprehension of extended spoken passages and to predict who will benefit the most from such interventions. Accomplishment of these aims will have both theoretical and clinical significance, allowing us to assess a theoretical model of audiovisual speech processing and to test ways for enhancing spoken language comprehension in older adults. Overall, this project represents a unique opportunity that brings together an aural rehabilitation specialist, cognitive psychologists, and a clinical research audiologist for the purpose of developing aural rehabilitation procedures for older adults that are grounded in a well-tested theoretical model and in an understanding of how cognitive measures relate to audiovisual speech comprehension.