How do we attend dynamically in time during listening?

言语往往难以理解，要么是由于情境要求（例如，在拥挤的酒吧里的背景言语），要么是由于与年龄相关的感觉系统变化导致言语编码退化。我的研究项目旨在提高我们对听觉编码和认知加工如何相互作用以形成听力体验和言语理解的基本机制的认识，以及神经回路中与年龄相关的变化如何导致不良的听力体验。这个项目的长期目标是提供机械基础，最终可以帮助有听力障碍的人更好地理解退化的语言，并使他们能够继续参与交流。我为NSERC DG提出的研究考虑了两个关键因素，这两个因素对现实生活中的语音理解至关重要，但迄今为止却很少受到关注：情景需求随着时间的推移而变化（例如，背景语音强度的变化），并不是所有的单词都与听者的对话相关。因此，听众可以专门在预计听力有困难的时候和预计会出现相关信息的时候参加，以避免疲劳。对时间和注意力大小的控制使倾听在时间上是动态的。老年与认知控制能力下降有关，但对于这如何影响动态地将注意力集中到声学环境中相关信息预期出现的时间点的能力，我们知之甚少。这项工作将提供听众在聆听过程中如何随时间动态参与的详细说明。本研究有四个具体目的：(1)考察个体在倾听过程中动态吸收注意力的能力；(2)研究语音相关信息（如时间规则、句法结构）对听者动态注意的时间影响；(3)识别支持动态注意力的关键脑区和网络；(4)探讨听力过程中注意力动态控制能力随年龄的变化。我们将采用一种综合的方法，结合行为，眼睛（瞳孔测量和微眼跳）和神经（电/脑磁图）的测量来全面表征人们在倾听过程中及时动态参与的能力，潜在的机制，以及衰老可能产生的影响。了解动态控制注意力的基本过程将有助于更好地了解导致不良聆听体验的因素。我们的工作将展示人们如何/何时参与到他们的倾听环境中，以及他们何时决定停止倾听。这对于创建包含所有能力的公共空间设计指南非常重要。我们的研究将进一步促进基于生理学的技术（如游戏），这些技术依赖于用户对注意力的动态调节。

Speech is often difficult to understand, either due to situational demands (e.g., background speech in a crowded bar), or due to age-related changes in sensory systems that result in degraded speech encoding. My research program aims to improve our knowledge of the fundamental mechanisms of how auditory sensory encoding and cognitive processing interact to shape listening experiences and speech comprehension, and how age-related changes in neural circuits lead to adverse listening experiences. The long-term goal of this program is to deliver the mechanistic foundations that ultimately can help people with hearing difficulties to comprehend degraded speech better and to enable them to stay engaged in communication. The research that I propose for this NSERC DG considers two key factors that are crucial for speech comprehension in real life but have thus far received little attention: situational demands vary over time (e.g., changes in the intensity of background speech) and not all words are relevant for a listener to follow a conversation. Listeners can thus attend specifically at times when listening is expected to be difficult and when relevant information is expected to occur in order to avoid fatigue. Control over the timing and magnitude of attention makes listening temporally dynamic. Older adulthood is associated with reduced cognitive control, but little is known about how this affects the ability to recruit attention dynamically to points in time when relevant information in acoustic environments is expected to occur. This work will deliver a detailed account of how listeners attend dynamically over time during listening. The proposed research has four specific aims: (1) to examine how well individuals can recruit attention dynamically during listening; (2) to investigate how speech-relevant information (e.g., temporal regularity, syntactic structure) affect dynamic attention in time during listening; (3) to identify the key brain regions and networks that support dynamic attention; and (4) to explore how the ability to control attention dynamically during listening changes with age. We will utilize an integrative approach that combines behavioral, eye (pupillometry & microsaccades), and neural (electro-/magnetoencephalography) measures to comprehensively characterize people's ability to attend dynamically in time during listening, the underlying mechanisms, and the effects aging may have. Understanding the fundamental processes that underlie dynamic control over attention will help gain better knowledge of the factors contributing to adverse listening experiences. Our work will demonstrate how/when people engage in their listening environments, and when they decide to stop listening. This will be important for creating guidelines for the design of public spaces that are inclusive of all abilities. Our research will further contribute to physiology-based technology (e.g., gaming) that relies on a user's dynamic regulation of attention.