Title: What the eyes can reveal about the ageing listening brain.
Funder: Economic and Social Research Council

Abstract: The ability to understand spoken language is a fundamental building block of successful communication. However, speech processing rarely takes place in ideal, laboratory-like environments. Instead, listeners must often contend with a backdrop of distracting noise or competing talkers (e.g., in cafeterias). Understanding speech in adverse conditions is known to rely on the integrity of domain-general cognitive functions (e.g., executive function, selective attention, processing speed). However, these higher-order cognitive capacities diminish with age. Owing to the combined effects of reduced sensory abilities (e.g., a hearing loss), an aging cognitive system, and the ubiquity of noise and other distractors in everyday listening environments, spoken language processing is often considered challenging and 'effortful' for older adults. However, the extent to which factors independent of hearing ability, namely attention and motivation, influence effortful listening in older adults remains unclear. One way to examine the effect of listener-controlled processes on effortful listening is by manipulating the cost/reward trade-off and measuring online changes in physiological arousal. Intentional Listening (IL) refers to the strategic use of attention during listening; a process thought to be influenced by motivation. By examining IL during adverse conditions, this project aims to explore the cognitive and physiological mechanisms that optimise the ability to overcome everyday listening challenges for older adults. The need to address communication difficulties in older adults is more critical than ever before owing to a rapidly growing elderly population. A better understanding of the communicative barriers faced by older adults, and crucially the ways in which they can be overcome, will help to mitigate social isolation and improve quality of life. This project will systematically test the predictions of a new Framework for Understanding Effortful Listening (FUEL) by teasing apart the complex interactions between IL, physiological arousal, and cognitive ability. The first aim of the project is to establish the relationship between physiological arousal and IL in young versus older adults using pupillometry. Pupillometry is an eye tracking technique that reveals moment-to-moment changes in physiological arousal and attention. The second aim of this project is to identify potential age-related differences in sustained attention by examining the time course of changes in physiological arousal during listening. The third aim is to uncover potential cognitive predictors of IL-based changes in physiological arousal by analysing individual differences in various cognitive abilities. Lastly, eye tracking techniques will be used to examine the influence of IL on the use of top-down (lexical-semantic) versus bottom-up (sensory) processing strategies in older adults. The visual world paradigm is now widely used in psycholinguistic research to investigate the precise timing of top-down processing operations (e.g., semantic integration) during spoken language understanding. Examining the effect of IL on the use of top-down processing strategies in older adults will help to elucidate the compensatory mechanisms that underlie IL-based changes in listening during adverse conditions. In summary, findings from this project will elucidate the impact of IL for elderly listeners in adverse conditions and, in doing so, will contribute to our theoretical understanding of the cognitive and physiological mechanisms that underlie effortful listening and how these processes undergo change into late adulthood.


Research activity codes: 1.2 PSYCHOLOGICAL AND SOCIOECONOMIC PROCESSES
Health categories: MENTAL HEALTH