Healthy aging in a social world: Investigating the impacts of cognitive and sensory decline on success in group conversation

听力科学和人类交流中的一个关键问题是理解听众如何注意到几个同时发言者中的一个，例如在拥挤的餐馆中。在这样的环境中，选择性注意允许听者专注于一个感兴趣的谈话者，同时过滤掉竞争的谈话者和噪音。然而，在多人说话的情况下，复杂性甚至更大，因为随着谈话流在说话者之间摆动，注意力必须在多个并发的说话者之间分配。老年人在日常对话环境中理解言语比年轻人更困难，这影响了他们参与对话的程度并影响了他们的生活质量。这些与年龄有关的困难可能归因于认知过程、感觉过程或两者的组合的变化。如果与他人轻松交谈的能力下降，这可能是毁灭性的，因此这项研究调查了与年龄有关的困难的基础。具体而言，本研究考察了不同听力障碍和年龄的成年人在多人环境中的会话处理，并将这些差异与认知和感觉处理技能联系起来，实验1将探讨会话难度如何随年龄变化，评估不同年龄组在会话话轮转换过程中转换听觉注意力的成本。参与者将被动地听成对的话语，这些话语要么都是由一个说话者发出的，要么在两个说话者之间切换。目标话语将同时通过扬声器阵列与掩蔽，和理解水平（通过多项选择题评估）将开关和非开关试验之间进行比较。受试者还将完成一系列认知测试和听觉功能测试，并将在不同年龄组之间比较转换说话者的效果，并与这些措施相联系。实验2将直接操纵年轻成年人的感觉和认知加工，试图模拟衰老的影响，探索退化的周边表征和认知负荷，影响了听者在多人谈话中转换注意力的能力。比较这些年轻人和实验1中老年人的行为，将有助于阐明困难主要是在识别竞争信息中的语音和单词，还是在将注意力调整到适当的声音上。最后，实验3将进一步检查真实的互动，使用语言理解，运动，以及说话者切换期间的凝视，以更好地理解复杂的现实生活环境中的会话处理。虽然这一阶段的工作细节将通过先前的实验得到通知，但进一步研究的可能性包括对新说话者的启动注意力的价值，以及不同听力设备模式的影响。虽然这个项目将开始利用已建立的范式，但它将朝着建立新的人际范式的方向发展，以生态有效的方式解决对话问题。因此，这项研究将有助于更全面地了解老年人在真实的多人环境中倾听谈话时遇到的困难，并可能导致支持认知和感官组件的新方法。

One of the key problems in hearing sciences and human communication is understanding how listeners can attend to one of several simultaneous speakers, e.g. in a crowded restaurant. In such environments, selective attention allows a listener to focus on one talker of interest while filtering out competing talkers and noise. However, in multitalker situations the complexity is even greater because, as the flow of conversation swings between talkers, attention must be distributed among multiple concurrent speakers. Older adults have more difficulty understanding speech in everyday conversational settings than their younger counterparts, which impacts how much they can take part in the conversation and affects their quality of life. These age-related difficulties may be attributed to changes in cognitive processes, sensory processes, or a combination of both. As it can be devastating if the ability to converse easily with others breaks down, this research investigates the basis of age-related difficulties. Specifically, this study examines conversation processing in multitalker environments in adults varying in hearing impairment and age, and links these differences to both cognitive and sensory-processing skills.Experiment 1 will explore how the difficulty of following conversation changes with age, assessing the costs of switching auditory attention during conversational turn-taking in different age groups. Participants will passively listen to pairs of utterances that are either both produced by one speaker, or that switch between two speakers. Target utterances will be presented concurrently with maskers through an array of loudspeakers, and comprehension levels (assessed through multiple choice questions) will be compared between switch and non-switch trials. Subjects will also complete a battery of cognitive tests and tests of auditory function, and the effect of switching talkers will be compared between age groups, and linked to these measures.Experiment 2 will directly manipulate sensory and cognitive processing in younger adults in an attempt to simulate the effects of aging, exploring the extent to which degraded peripheral representations, and cognitive load, affects the ability of listeners to switch attention in multitalker conversations. Comparing the behaviour of these younger adults, and the older adults in experiment 1, will help shed light on whether the difficulty is principally in identifying speech sounds and words in the competing messages, or in tuning attention to the appropriate voice.Finally, experiment 3 will move towards an examination of real interaction, using measures of linguistic comprehension, movement, and gaze during talker switches to better understand conversation processing in complex real-life environments. While the detail of this stage of work will be informed by the prior experiments, possibilities for further study include the value of priming attention towards a new speaker, and the impact of different hearing device modes.While this project will begin by making use of established paradigms, it will then move towards building new interpersonal paradigms to address conversation in an ecologically valid manner. This research will therefore contribute to a more complete picture of the difficulties that older adults experience when listening to conversation in real multitalker environments, and could lead to new ways of supporting the cognitive and sensory components of aging in tandem.