ADVANCING CLINICAL PRACTICE AND ESTABLISHING FOUNDATIONAL THEORY FOR AUDITORY FUNCTION IN INDIVIDUALS WITH DOWN SYNDROME

项目总结/摘要 高达80%的唐氏综合征患者在整个生命周期中都有听力损失，包括波动性听力损失。 传导性听力损失和永久性感音神经性听力损失。早发性老年性耳聋也被观察到， 这一人口，与在其他领域观察到的早熟老龄化一致。然而，大多数现有的流行率 数据来自对生活在并发症机构中的个人的病历审查或评估。 适用于一般人群中的唐氏综合征患者。患有唐氏综合症的人 与神经典型个体相比，颅骨解剖结构的差异，包括预测 听力损失和渗出性中耳炎（OME）的发病率较高。然而，这些因素也会影响刺激措施。 呈现水平。具体来说，狭窄的耳道和OME都导致刺激水平增加;听力 如果在刺激校准或呈现期间不考虑这些因素，则可能低估损失。 重要的是，这个问题可能有助于缩短听觉脑干反应（ABR）以前的研究结果 波形潜伏期为个体与唐氏综合征相对于年龄匹配的神经正常的同龄人，一个度量有用 用于传导性听力损失的临床诊断， 无法获得。AIM 1定义了听力损失的患病率、类型和轨迹， 唐氏综合症在普通人群中。临床听力学的重大创新是通过严格的 校准技术，这将解决ABR延迟的问题，并提供有关外围设备的全面数据。 整个生命周期的敏感性。就像神经正常人群一样，听力损失使个体患有Down 综合征的风险，沟通，学习，社会化和就业机会的重大挑战。 具体来说，感音神经性听力损失导致宽的听觉滤波器带宽限制了准确识别 的语音。在唐氏综合征患者中观察到的小脑和皮质体积较低， 与跨领域的时间处理困难相关，并可能影响简短的显着性 在背景噪声中收听时的信噪比改善。而认知和语言 有助于在神经典型人群中成功地进行掩蔽语音识别， 困难和智力残疾可能会损害唐氏症患者的功能性听力能力， 综合征AIM 2建立了关于个人功能性听觉能力的基础理论， 唐氏综合征由掩蔽言语感知模型指导，包括可听度、心理物理 频谱和时间分辨率的测量，以及选择性注意的神经心理因素，工作 记忆和词汇知识。

PROJECT SUMMARY/ABSTRACT Up to 80% of individuals with Down syndrome have hearing loss across the lifespan, including fluctuating conductive hearing loss and permanent sensorineural hearing loss. Early onset presbycusis is also observed for this population, consistent with precocious aging observed in other domains. However, most existing prevalence data were obtained from medical record review or assessment of individuals living in institutions complicating application to individuals with Down syndrome in the general population. Individuals with Down syndrome have structural differences in cranial anatomy compared to neurotypical individuals, including that which would predict high rates of hearing loss and otitis media with effusion (OME). However, these factors can also impact stimulus presentation level. Specifically, stenotic ear canals and OME both result in increased stimulus levels; hearing loss may be underestimated if these factors are not considered during stimulus calibration or presentation. Critically, this issue may have contributed to previous findings of shortened auditory brainstem response (ABR) waveform latency for individuals with Down syndrome relative to age-matched neurotypical peers, a metric useful for clinical diagnosis of conductive hearing loss in individuals for whom a reliable behavioral response to sound is unable to be obtained. AIM 1 defines the prevalence, type, and trajectory of hearing loss for individuals with Down syndrome in the general population. Significant innovation to clinical audiology is gained using rigorous calibration techniques, which will resolve the issue of ABR latency and provide comprehensive data on peripheral sensitivity across the lifespan. Just as for neurotypical populations, hearing loss puts individuals with Down syndrome at risk for major challenges to communication, learning, socialization, and employment opportunities. Specifically, sensorineural hearing loss results in broad auditory filter bandwidths limiting accurate identification of speech sounds. Low cerebellar and cortical volumes observed in individuals with Down syndrome are associated with temporal processing difficulties across domains and may impact the saliency of brief improvements in signal-to-noise ratio when listening in background noise. Whereas cognition and language contribute to successful masked speech recognition in neurotypical populations, high rates of language difficulties and intellectual disability are likely to undermine functional hearing abilities for individuals with Down syndrome. AIM 2 establishes foundational theory regarding the functional auditory abilities of individuals with Down syndrome guided by a model of masked speech perception that includes audibility, psychophysical measures of spectral and temporal resolution, and neuropsychological factors of selective attention, working memory, and vocabulary knowledge.