Spatiotemporal Dynamics of Language Processing in School-Age Children with Mild-to-Severe Hearing Loss

项目总结/摘要 听力损失的儿童有明显的语言障碍的风险，这会导致教育困难。 和职业环境的影响。然而，听力损失儿童的语言延迟并不是 普遍存在;有些孩子明显落后于听力正常的孩子（CNH），而另一些孩子则表现得更好。 与CNH类似。最近在轻度至重度听力损失儿童中的工作（即，重听儿童 [CHH]）表明语言障碍的程度与听觉剂量相关， 助听器的使用频率取决于助听器提供语音访问的程度和助听器的使用量。 尽管如此，听觉通路（即，听力损失和听觉剂量）和语言 功能尚不清楚。此外，听觉通路对语言相关神经振荡动力学的影响 是完全未知的。拟议的职业生涯早期R21项目将提供关于以下影响的关键新数据： 学龄儿童听觉通路的变异性对语言功能和神经元动力学的多层次影响。 我们有希望的初步工作表明，脑磁图（MEG）的非侵入性成像可以 精确地检测支持整个左侧化语言的语言处理的神经模式 网络，并可以量化改变神经元活动和听觉剂量之间的关系， 嘘。在目前的研究中，我们将描述听觉通路，语言处理， CHH和人口统计学匹配的CNH的大队列中的神经发育。参与者将经历 在一系列语言任务、结构MRI、神经心理学和听力测试中进行基于任务的MEG 试验.在目标1中，我们将确定行为差异背后的时空振荡动力学 在CHH和人口统计学匹配的CNH之间观察到的语言处理。语言缺陷 CHH中的加工将与增加的任务相关神经活动和改变的功能连接相结合 在整个左偏侧语言网络中。CHH还将招募同源的语言相关区域， 右半球，指示补偿机制，和网络水平的振荡畸变将 预测任务性能。在目标2中，我们将描述听觉剂量对语言处理的影响 性能和神经生理学。我们假设，高听觉剂量的CHH会表现出更好的 语言任务的表现以及与语言相关的神经活动更加正常化。此外，我们假设 助听器的使用和安装的个人贡献将取决于听力损失的程度， 助听器的使用将对轻度听力损失的儿童产生更大的影响，而助听器的可听度将 儿童听力损失越严重，影响因素越显著。这项研究将提供精确的，定量的 标记支持语言发展的关键方面，并将确定个人和添加剂的贡献 助听器的选配和使用。这些数据将有助于描述 语言障碍的CHH，并用于优化治疗干预。

Project Summary/Abstract Children with hearing loss are at risk for significant language delays, which cascade into difficulties in educational and vocational settings throughout the lifespan. However, language delays in children with hearing loss are not universal; some children fall significantly behind children with normal hearing (CNH), while others perform similarly to CNH. Recent work in children with mild-to-severe hearing loss (i.e., children who are hard-of-hearing [CHH]) who wear hearing aids suggests that the degree of language impairment correlates with auditory dosage, defined by both the degree to which a hearing aid provides access to speech and the amount of hearing aid use. Nonetheless, the relationship between auditory access (i.e., hearing loss and auditory dosage) and language function is still unclear. Further, the impact of auditory access on language-related neural oscillatory dynamics is completely unknown. The proposed early-career R21 project will provide pivotal new data on the impact of variability in auditory access on multiple tiers of language function and neuronal dynamics in school-age children. Our promising preliminary work shows that noninvasive imaging with magnetoencephalography (MEG) can precisely detect the neural patterns supporting language processing throughout the left-lateralized language network in children and can quantify the relationship between altered neuronal activity and auditory dosage in CHH. In the current study, we will characterize the associations between auditory access, language processing, and neural development in a large cohort of CHH and demographically matched CNH. Participants will undergo task-based MEG during a battery of language tasks, structural MRI, and neuropsychological and audiometric testing. In Aim 1, we will identify the spatiotemporal oscillatory dynamics that underlie the behavioral differences in language processing observed between CHH and demographically matched CNH. Deficits in language processing in CHH will be coupled with increased task-related neural activity and altered functional connectivity throughout the left-lateralized language network. CHH will also recruit homologous language-related regions in the right hemisphere, indicative of a compensatory mechanism, and network-level oscillatory aberrations will predict task performance. In Aim 2, we will characterize the impact of auditory dosage on language processing performance and neurophysiology. We hypothesize that CHH with higher auditory dosage will exhibit better performance in language tasks and more normalized language-related neural activity. Further, we hypothesize that the individual contributions of hearing aid use and fit will depend on the degree of hearing loss, such that hearing aid use will have a greater effect on children with milder hearing loss, while hearing aid audibility will be the more significant factor in children with more severe hearing loss. This study will provide precise, quantitative markers supporting key facets of language development and will identify the individual and additive contributions of malleable auditory factors such as hearing aid fit and use. These data will help characterize the nature of language impairments in CHH and be used to optimize therapeutic interventions.