Neural measures of temporal processing deficits affecting speech comprehension in listeners with normal hearing thresholds

时间处理缺陷的神经测量影响听力阈值正常的听众的言语理解

• 批准号: 10382033
• 负责人: Mishaela T DiNino
• 金额: $ 1.66万
• 依托单位: CARNEGIE-MELLON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-01 至 2021-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10382033
• 关键词: Acoustic Nerve; Acoustics; Adult; Affect; Animal Experimentation; Animal Model; Area; Attention; Attenuated; Auditory; Auditory Perception; Auditory Threshold; Behavioral; Brain; Cell physiology; Characteristics; Cochlea; Code; Communication; Communication impairment; Comprehension; Consensus; Cues; Diagnostic tests; Discrimination; Electroencephalography; Environment; Exhibits; Exposure to; Frequencies; Goals; Grouping; Hair Cells; Human; Impairment; Individual; Investigation; Knowledge; Lead; Link; Measures; Mechanics; Mentors; Methods; Nerve Fibers; Noise; Participant; Pattern; Perception; Performance; Phase; Physiological; Population; Process; Psychophysics; Quality of life; Research; Scientist; Signal Transduction; Speech; Speech Sound; Stimulus; Stream; Sum; Symptoms; Synapses; Training; Variant; Voice; Work; Workplace; attentional control; attentional modulation; auditory processing; auditory stimulus; career; cochlear synaptopathy; comprehension deficit; experience; experimental study; hearing impairment; noise perception; normal hearing; novel; relating to nervous system; response; segregation; selective attention; signal processing; social; sound; speech in noise; standard measure

PROJECT SUMMARY/ABSTRACT Some individuals with normal hearing thresholds (NHTs) demonstrate considerable challenges perceiving speech in the presence of background noise. Evidence from recent studies suggests that this impairment may be the result of cochlear synaptopathy (CS), degeneration of the synapses between cochlear hair cells and the auditory nerve, observed in animal models following exposure to high-intensity noise that does not permanently alter hearing thresholds. Still, it is not known exactly how noise-induced CS would contribute to impairments in speech-in-noise perception in humans with NHTs. CS engenders auditory nerve fiber degeneration and weakens auditory nerve phase-locking to the precise timing information in auditory signals; therefore, the goal of this research is to determine whether temporal processing impairments from noise- induced CS are consistent with speech-in-noise perceptual deficits in listeners with NHTs. This investigation will contrast listeners with high- and low-likelihood of noise-induced CS, as assessed by a measure of summed auditory nerve fiber responses, on two mechanisms for segregating speech streams that depend on accurate coding of precise timing information. Aim #1 of this investigation will examine use of interaural timing difference cues for spatial attention to speech streams and the degree to which attention to a target stream modulates cortical responses. Aim #2 will utilize a novel task to assess participants’ ability to use pitch cues that can only be coded by auditory nerve phase-locking to perceptually separate speech streams. Cortical entrainment to the temporal envelope of speech, which has been shown to increase perceptual representation of individual streams, will also be examined during this paradigm. Compared to participants with a low likelihood of CS, it is expected that those with a high likelihood of having CS will perform more poorly on tasks that require use of precise timing cues to segregate speech sounds from competing streams. These listeners should also demonstrate lower cortical modulation and neural synchrony to speech streams, demonstrating that bottom-up deficits in temporal encoding alter neural representations of speech in the presence of competing sounds. These findings will provide support for a link between noise-induced CS and impaired speech understanding in noise in listeners with NHTs and will provide valuable knowledge of the contributors to this communication impairment. This research will take place in an exceptional training environment and the PI will be mentored by two knowledgeable, accomplished scientists. These experiments will provide the PI with training in psychophysical task construction, brain activity recording, and signal processing methods and will prepare her well for a career as an independent scientist.

项目摘要/摘要 一些患有正常听力阈值（NHT）的人表现出巨大的挑战 在背景噪音的存在下感知语音。最近研究的证据表明 这种障碍可能是人工耳蜗突触病（CS）的结果 耳蜗毛细胞和听觉神经之间的突触，在动物模型中观察到 暴露于不会永久改变听力阈值的高强度噪声。不过，不是 确切知道噪声引起的CS将如何导致语音中的障碍 人类具有NHT的感知。 CS产生听觉神经纤维变性并削弱 听觉神经相锁定在听觉信号中的精确计时信息；因此， 这项研究的目的是确定噪声的临时处理障碍是否存在 诱导的CS与NHTS的听众中定义了噪音的语音一致。这 调查将与评估的噪声引起的CS相比，将听众与噪声诱导的CS进行对比 通过夏季听觉神经纤维反应的量度，在两种隔离机制上 语音流取决于精确定时信息的准确编码。目的＃1 调查将检查使用交互式时序差线提示的使用，以使空间关注语音 流和注意目标流的程度调节皮质反应。目的 ＃2将利用新颖的任务来评估参与者使用只能编码的音调提示的能力 通过听觉神经相锁定，可以感知分开的语音流。皮质园艺 到暂时的语音信封，这已被证明会增加感知表示 在此范式中，也将检查单个流的单个流。与参与者相比 CS的可能性很小，预计患有CS的可能性很高 在需要使用精确的定时提示的任务上更糟糕 竞争流。这些听众还应显示较低的皮质调制和中性 与语音流同步，证明自下而上的临时编码定义 在竞争声音的情况下，言语的神经表示。这些发现会 为噪声引起的CS与噪声中的语音理解受损之间的联系提供支持 在具有NHTS的听众中，将为此贡献者提供宝贵的知识 沟通障碍。这项研究将在特殊的培训环境中进行 PI将由两位知识渊博，有成就的科学家考虑。这些实验 将为PI提供心理物理任务构建，大脑活动记录和 信号处理方法，并将为她的职业做好准备。