How do we attend dynamically in time during listening?

由于情景需求(例如，拥挤酒吧中的背景语音)，或者由于导致语音编码退化的感觉系统的年龄相关变化，语音通常难以理解。我的研究项目旨在提高我们对听觉感觉编码和认知加工如何相互作用以塑造听力体验和言语理解的基本机制的了解，以及神经回路中与年龄相关的变化如何导致不利的听力体验。该计划的长期目标是提供机械基础，最终帮助听力有困难的人更好地理解退化的语音，并使他们能够保持沟通。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言语理解至关重要，但到目前为止还没有得到多少关注：情景需求随着时间的推移而变化(例如，背景演讲强度的变化)，并且并不是所有的单词都与听者跟随对话相关。因此，听者可以在预计听起来困难的时候和相关信息预计会出现的时候参加，以避免疲劳。对注意力的时间和大小的控制使倾听在时间上是动态的。成年年龄越大，认知控制能力越弱，但人们对这如何影响人们对声学环境中相关信息预计会出现的时间点的关注的能力知之甚少。这项工作将详细描述听众在收听过程中如何随着时间的推移动态地参与。这项研究有四个具体目的：(1)考察个体在听力过程中如何动态地吸引注意力；(2)考察与言语相关的信息(如时间规律性、句法结构)如何在听力过程中及时影响动态注意；(3)确定支持动态注意的关键脑区和网络；(4)探索听力过程中动态控制注意力的能力如何随年龄变化。我们将利用一种结合行为、眼睛(瞳孔测量和微眼跳)和神经(脑电/脑磁图)测量的综合方法来全面表征人们在聆听过程中及时动态注意的能力、潜在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听力体验的因素。我们的工作将展示人们如何/何时参与他们的倾听环境，以及他们何时决定停止倾听。这对于创建包容所有能力的公共空间设计指导方针将是重要的。我们的研究将进一步促进基于生理学的技术(例如，游戏)，这种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.