THE NEUROCOGNITIVE BASIS OF EFFORTFUL LISTENING

 描述(由申请人提供)：大约3600万美国人报告有不同程度的听力障碍。听力损失与社会孤立、抑郁、认知能力下降以及由于工作效率降低而造成的经济成本有关。因此，了解如何优化听力障碍听众的交流是言语知觉研究人员面临的一个关键挑战。最近研究的一个标志是听力努力概念的发展，该概念强调了言语感知过程中认知处理的重要性：听力障碍的听众通常可以理解口语，但随着认知努力的增加，注意力和记忆等其他过程的资源被抢走。不幸的是，在努力的过程中发挥作用的特定认知过程 人们对倾听仍然知之甚少。目前这项研究的目的是提供一个更具体的描述神经和认知系统涉及努力听力，并调查这些因素如何影响言语理解。这些研究是围绕词汇竞争的框架设计的，词汇竞争指的是听者如何从他们可能听到的单词中选择正确的目标单词(那个单词是“帽”还是“猫”？)。词汇竞争受到以下因素的影响：单个单词的特性(发音与许多其他单词相似的单词，如“猫”，更难处理)，声音信号(声音清晰度较差，使正确识别更困难)，以及认知加工中的个体差异(抑制能力较低，更容易感知错误目标)。在神经解剖学上，这些过程由颞叶和额叶皮质的可分离区域支持，与支持语音理解的大规模皮质网络一致。重要的是，听力障碍和认知能力的个体差异与正在处理的言语类型相互作用，决定了听者理解言语的成功程度。目前的研究将涉及收集所有参与者的听力和认知指标，以调查这些指标的个体差异如何影响言语感知。来自行为学研究、眼球追踪和功能磁共振成像(FMRI)的综合证据将被用来探索语音感知的认知和神经基础。目的1评价言语感知过程中词汇竞争与听力努力之间的关系。目的2描述处理退化语音的多个认知过程。目的3根据词汇竞争的理论框架，评估听觉和认知的个体差异如何预测言语知觉。这些研究将显示词汇竞争与处理退化语音时的认知过程之间的关系，为更好地解释听力正常和听力受损的听者所面临的挑战提供了一个有理论动机的框架。

 DESCRIPTION (provided by applicant): Approximately 36 million Americans report having some degree of hearing impairment. Hearing loss is associated with social isolation, depression, cognitive decline, and economic cost due to reduced work productivity. Understanding ways to optimize communication in listeners with hearing impairment is therefore a critical challenge for speech perception researchers. A hallmark of recent research has been the development of the concept of listening effort, which emphasizes the importance of cognitive processing during speech perception: Listeners with hearing impairment can often understand spoken language, but with increased cognitive effort, taking resources away from other processes such as attention and memory. Unfortunately, the specific cognitive processes that play a role in effortful listening remain poorly understood. The goal of the current research is to provide a more specific account of the neural and cognitive systems involved in effortful listening, and investigate how these factors affect speech comprehension. The studies are designed around a framework of lexical competition, which refers to how listeners select a correct target word from among the possible words they may have heard (Was that word "cap" or "cat"?). Lexical competition is influenced by properties of single words (words that sound similar to many others, like "cat", are more difficult to process), the acoustic signal (poorer acoustic clarity makes correct identification more difficult), and individual differences in cognitive processing (lower inhibitory ability makes incorrect targets more likely to be perceived). Neuroanatomically, these processes are supported by dissociable regions of temporal and frontal cortex, consistent with a large-scale cortical network that supports speech comprehension. Importantly, individual differences in both hearing impairment and cognitive ability interact with the type of speech being processed to determine the level of success a listener will have in understanding speech. The current research will involve collecting measures of hearing and cognition in all participants to investigate how individual differences in these measures impact speech perception. Converging evidence from behavioral studies, eyetracking, and functional magnetic resonance imaging (fMRI) will be used to explore the cognitive and neural basis of speech perception. Aim 1 evaluates the relationship between lexical competition and listening effort during speech perception. Aim 2 characterizes multiple cognitive processes involved in processing degraded speech. Aim 3 assesses how individual differences in hearing and cognition predict speech perception, relying on a framework of lexical competition to inform theoretical interpretation. These studies will show a relationship between lexical competition and the cognitive processes engaged when processing degraded speech, providing a theoretically-motivated framework to better explain the challenges faced by both normal-hearing and hearing-impaired listeners.