Physiological markers of listening effort and their dependence on age

言语理解是人类听觉的一项关键功能，在学习、职业和社会生活中具有重要作用。 社会功能。衰老与语音识别的困难增加有关，特别是在嘈杂的环境中。 背景，虽然传统的临床测试经常无法解释主观言语感知， 困难越来越多的研究发现，认知资源的补偿性使用增加， 这被称为听力努力（LE），是老龄化和听力受损人群中的一个关键变化。 因此，LE的准确测量可以作为量化主观的重要客观诊断工具， 言语知觉缺陷虽然已经提出了多种用于量化LE的方法，但是关于LE的定量方法知之甚少。 这些措施是否反映了相同的基本认知过程的使用，特别是在 在其他有意义的言语掩蔽者在场的情况下的连续言语。此外，人们对是否 LE的改变影响较低和较高级别特征的处理（例如，声学包络与词汇包络） 听觉皮层的各个层次。这项建议将填补我们知识中的这些重要空白。在 目标1，我们将通过改变语音识别中的信噪比或空间线索来操纵LE需求 任务利用孤立的句子掩盖了竞争语音，同时测量三种常用的措施， LE（自我报告，瞳孔大小和α波段功率的神经测量）。然后我们将这些措施 以确定它们是否被可懂度操纵类似地调制， 共同的潜在认知过程在目标2中，我们将解决两个关键问题。首先，我们将测试 目标1中使用的LE测量在更自然的背景下表现出彼此相似的关系， 连续语音，更接近模仿的情况下，语音感知困难， 遇到的。其次，我们将使用先进的基于模型的分析来分解语音诱发的 将脑电图活动转化为对被关注和被忽视的较低和较高水平特征的反应 言语并评估LE操作如何调节这些表示。这样做，我们将获得新的见解 高级认知过程和语言处理途径之间的相互作用， 皮质，可能揭示LE的新神经特征。最后，为了更深入地了解衰老的影响， 在LE和语音处理方面，我们将评估每个Aim的关键指标如何随年龄变化。这 这项工作将为今后的研究提供基础，旨在更详细地描述不同的 参与LE的认知过程对注意和忽略语音的皮层处理，具有潜在的 在语音处理缺陷的诊断中的应用，特别是在标准临床测试 未能检测到损伤，并在测试语音感知的好处，从新的算法用于听力- 辅助设备。

Speech understanding is a key function of human audition with important roles in learning, professional, and social functions. Ageing is associated with increased difficulties with speech recognition, particularly in noisy backgrounds, although traditional clinical tests frequently fail to account for subjective speech perception difficulties. A growing body of work has identified increased compensatory use of cognitive resources, collectively known as listening effort (LE), as a key change within the ageing and hearing-impaired populations. Consequently, accurate measures of LE may serve as critical objective diagnostic tools for quantifying subjective speech perception deficits. While multiple methods for quantifying LE have been proposed, little is known about whether these measures reflect usage of the same underlying cognitive processes, particularly in the context of continuous speech in the presence of other meaningful speech maskers. Moreover, little is known about whether changes in LE affect processing of lower- and higher-level features (e.g., acoustic envelope vs. lexical surprisal) throughout the auditory cortical hierarchy. This proposal will address these important gaps in our knowledge. In Aim 1, we will manipulate LE demands via changes in signal-to-noise ratio or spatial cues in a speech recognition task utilizing isolated sentences masked by competing speech, while measuring three commonly used measures of LE (self-report, pupil size, and neural measure of alpha band power). We will then correlate these measures with one another to determine whether they are similarly modulated by intelligibility manipulations, indicating common underlying cognitive processes. In Aim 2, we will address two key questions. First, we will test whether the LE measures used in Aim 1 exhibit similar relationships with one another in the context of more naturalistic, continuous speech, more closely mimicking scenarios in which speech perception difficulties are commonly encountered. Second, we will use advanced model-based analyses to decompose speech-evoked electroencephalographic activity into responses to lower- and higher-level features of both attended and ignored speech and assess how LE manipulations modulate these representations. Doing so, we will gain novel insights into the interaction between higher-order cognitive processes and the language processing pathways in the cortex, potentially revealing new neural signatures of LE. Finally, to gain deeper understanding of aging effects on LE and speech processing, we will assess how each Aim’s key measures change as a function of age. This work will provide foundation for future studies aimed at a more detailed characterization of the effects of different cognitive processes involved in LE on cortical processing of attended and ignored speech, with potential applications in diagnostics of speech processing deficits, particularly in scenarios where standard clinical tests fail to detect an impairment, and in testing speech-perception benefits from new algorithms used in hearing- assisting devices.