Abstract

Epidemiological research indicates a link between hearing loss and poor mobility (Lin & Ferrucci, 2012; Viljanen et al., 2009). One explanation for this association is cognitive compensation, wherein older adults compensate for hearing loss and declines in mobility by recruiting higher-level cognitive resources. A growing body of research using various approaches demonstrates that cognitive resources are involved in both hearing and mobility with age. Our work complements these studies by using experimental, intervention and modeling techniques to investigate how these domains relate in an aging population.
Using an experimental approach, older adults and older adults with hearing loss completed a cognitive-motor dual-task protocol, in which they performed an auditory working memory task and a balance recovery task singly or concurrently. Older adults with mild hearing loss showed disproportionately greater dual-task costs on the auditory working memory task, particularly when auditory challenge was added. Given the involvement of cognitive resources in challenging dual-task conditions and particularly among a hearing loss population, the second study took a cognitive enhancement approach. Specifically, older adults with and without hearing loss were given either simultaneous or sequential cognitive-physical training formats. While sequential training appeared to benefit performance on the auditory working memory task, older adults with hearing loss appeared to improve on this same task regardless of format. To complement these group-wise effects we took a structural equation modeling approach using data pooled from the two previous studies to examine individual differences in hearing and cognition which might influence mobility. An additional consideration was the impact of self-efficacy. It was found that the association between greater hearing loss and reduced mobility was mediated by cognitive status, and that self-efficacy in the hearing domain may be an important contributor to balance confidence.
Taken together, the current work points to the importance of cognitive resources in both sensory and motor aging, particularly among older adults with age-related hearing loss. As such, the work suggests that cognitive remediation may be a useful complement to traditional hearing and mobility rehabilitation. Moreover, self-efficacy appears to be an important contributor in understanding the relation between hearing loss and mobility.