Speech communication in older adults: an acoustic and perceptual investigation – ESRC

Abstract

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. In our project, we gained a comprehensive account of older people's speech production and perception in situations involving communication with another individual. Older adults with age-related hearing loss and the rarer group of older adults with normal hearing were included in the study, as well as younger adult controls. In Study 1, participants were recorded while they completed a problem-solving task with another person. Communication between the participants was either in good listening conditions, where both speakers could hear each other normally, or in adverse conditions. There, one of the participants had to get their message across to another speaker who has a simulated hearing loss or when both were speaking in a noisy background. These comparisons enabled 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. High-quality recordings were made of these interactions and these were used to carry out acoustic analyses of their speech and also analyses of interactional features such as eye gaze and turn-taking. In Study 2, older and younger listeners with normal and impaired hearing were presented some of the materials recorded in Study 1 in good and adverse listening conditions. Intelligibility tests will be run to see what impact age and hearing status have on speech understanding and to see whether the 'clear speech' adaptations made by older speakers to counter the effects of poor communication conditions gave the same benefit to that of younger speakers. This project aims to 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 also assists 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 also contributes to our basic understanding of speech perception and production development across the lifespan.