Listen Carefully: Healthcare design for listening effort and cognitive function

Hearing loss is one of the most common conditions affecting older adults and is one of the largest risk factors for dementia at mid-stages of life. Despite increasing evidence of the association between hearing loss and dementia, little is known about the mechanisms underlying this association. In addition, there are a lack of pathways linking the cognitive and hearing healthcare systems. Dementia is one of the greatest health challenges for an ageing population. There is no cure for dementia, which places greater focus on disease management and early prevention.

This thesis uses a hospital’s memory clinic as an entry point to present an interdisciplinary collaboration at the intersection of hearing and cognitive healthcare—two complex social systems that are seldom integrated in practice. This thesis combines clinical research and design to explore the integration of hearing-based interventions and technologies into cognitive healthcare.

The research focuses on patients with mild cognitive impairment (MCI) and cognitively healthy older adults. Those with MCI have preserved function in daily activities, but have a minor impairment in one or multiple domains of cognitive functioning. As this group is at a higher risk for further cognitive decline, they may benefit most from early-stage identification and intervention.

With the overarching aim of exploring the closer integration of hearing-based interventions in cognitive healthcare, the thesis presents four sub-studies. Following the published study protocol (Paper A) the first study investigates the cognitive load hypothesis by exploring listening effort using pupillometry and its association with cognitive function in normal hearing older adults with MCI (Paper B). The second study examines the effect of hearing aid use on those with MCI using the same listening effort paradigm (Working Paper C). The third study explores the barriers and benefits of hearing aid use for those with MCI and uses these to structure training and guidance for successful hearing aid adoption among those with cognitive dysfunction (Working Paper D). The fourth study investigates the prevalence, awareness, and treatment of hearing loss among patients with MCI in the memory clinic setting (Working Paper E). Taken together, these studies represent the exploration of new routines and care pathways for hearing-based interventions aimed at prevention and management among an atrisk clinical population.

Overall, this thesis provides a design-based approach to preventative healthcare, exploring how research can build knowledge, mediate a change of routines, and illuminate potential new system structures. The results illustrate the hearing and listening difficulties present among those with MCI, and suggest strategies for approaching identification, treatment, and management at the intersection of hearing and cognitive health that may protect against further cognitive decline.