Speech communication in older adults: an acoustic and perceptual investigation

由于65岁以上常见的与年龄相关的听力损失、与年龄相关的发音和语音清晰度下降，以及短期记忆和处理速度较差等认知问题的综合影响，老年人可能难以进行语言交流。过去关于老年人如何感知和产生语音的研究倾向于使用受控材料，如朗读单词或句子，独立地考虑这些能力。这些研究很少告诉我们老年说话者在使用言语进行交流时是如何运作的，以及这些不同因素是如何相互作用的。例如，有研究表明，老年人在对话中看到对话者会受益，但视听语音比听觉语音对认知加工的要求更高，这导致听者努力增加，信息回忆减少。在我们的项目中，我们建议对老年人在与另一个人进行交流的情况下的言语产生和感知进行全面的描述。与年龄相关的听力损失的成年人和听力正常的较罕见的老年人组将包括在内，以及年轻人对照组。在研究1中，在阅读句子或完成一项解决问题的任务时，与另一位说话者的交流要么处于良好的倾听条件，即双方都能正常听到对方的声音，要么处于不利的条件，即参与者必须将他们的信息传达给另一位模拟听力损失的说话者，或者当两人都在嘈杂的背景下说话时。这些比较将使我们能够感觉到老年人在多大程度上能够调整他们的语言来克服困难的听力条件，这是一项在日常生活中言语交流中至关重要的技能。我们将获得参与者语音的高质量数字录音，但也将通过安装在脖子上的传感器记录他们声带振动的信息，这决定了他们的声音质量。视频记录也将被分析，以调查年长的说话者是否像年轻的说话者一样，利用眼睛凝视和头部手势来表示话语的方方面面，如话轮转向和后向沟通(例如，说‘好的’以表示理解)。在研究2中，听力正常和受损的年长和年轻的听者将被所有处于良好和不利听力条件下的说话者小组呈现在研究1中记录的一些句子材料中。测试将在听觉和视听两种条件下进行。将进行可理解性测试，以了解年龄、听力状况和视觉线索对语音理解的影响，并看看年龄较大的说话者为应对糟糕的交流条件而进行的“清晰语音”适应是否会对年轻说话者产生同样的好处。此外，还将进行句子回忆测试，以调查听力是否降低了听清楚语音的努力。该项目将使人们更好地了解老龄化对言语交流的影响，以及在一群健康的老年人中可能导致言语交流能力下降的各种因素。这些基准将对从事与患有健康并发症的老年人交流方面工作的语言和语言治疗师以及听觉学家等从业者有用。更好地了解老年人遇到的沟通困难及其克服这些困难的战略，也将有助于社会工作者和护理专业人员等致力于改善老年人生活质量的专业人员，以及远程医疗和远程监测语音技术设备的开发人员。重要的是，这项研究还将有助于我们对言语知觉和语言产生发展的基本理解。

Speech communication can be difficult for older people, due to the combined effects of age-related hearing loss, which is common over the age of 65, age-related decline in the quality of phonation and speech articulation, and cognitive problems such as poorer short-term memory and processing speed. Past studies of how older individuals perceive and produce speech sounds have tended to consider these abilities independently of each other using controlled materials, such as read words or sentences. These studies tell us little about how older speakers function when using speech for communicative purposes, and how these various factors interact. For example, it has been shown that older people benefit from seeing their interlocutor in conversations, but audiovisual speech places greater demands on cognitive processing than auditory speech which leads to increased listener effort and reduced information recall. In our project, we propose to gain a comprehensive account of older people's speech production and perception in situations involving communication with another individual. Adults with age-related hearing loss and the rarer group of older adults with normal hearing will be included as well as younger adult controls. In Study 1, communication with another speaker, while reading sentences or completing a problem-solving task, will either be in good listening conditions, where both speakers hear each other normally, or in adverse conditions, where the participant has to get their message across to another speaker who has a simulated hearing loss or when both are speaking in a noisy background. These comparisons will enable us to get a sense of the degree to which an older person is able to adapt their speech to overcome difficult listening conditions, a skill which is of paramount importance in speech communication in everyday life. We will obtain high-quality digital recordings of the participants' speech but will also, via sensors placed on the neck, record information about their vocal fold vibration, which determines the quality of their voice. Video recordings will also be analysed to investigate whether older speakers make use of eye gaze and head gestures to signal aspects of discourse such as turn-taking and back-channelling (e.g., saying 'okay' to signal understanding), to the same degree as younger speakers. In Study 2, older and younger listeners with normal and impaired hearing will be presented some of the sentence materials recorded in Study 1 by all speaker groups in good and adverse listening conditions. Tests will be presented in both auditory-alone and audiovisual conditions. Intelligibility tests will be run to see what impact age, hearing status and visual cues have on speech understanding and to see whether the 'clear speech' adaptations made by older speakers to counter the effects of poor communication conditions gives the same benefit to that of younger speakers. Sentence recall tests will also be run to investigate whether the listening effort is reduced listening to 'clear speech'. This project will lead to a better understanding of the effects of ageing on speech communication and of the various contributing factors to potentially degraded speech communication in a population of 'healthy aged' individuals. These benchmarks will be of use for practitioners such as speech and language therapists and audiologists who work on aspects of communication with older people who have health complications. A better understanding of communication difficulties that older individuals experience and of their strategies to overcome these difficulties will also assist professionals such as social workers and care professionals who work to improve quality of life for older people, as well as developers of speech technology devices for telemedicine and remote monitoring. Importantly, this research will also contribute to our basic understanding of speech perception and production development across the lifespan.