Effects of Familiarization on Intelligibility of Dysarthric Speech in Older Adults With and Without Hearing Loss

Abstract

Purpose: Familiarization tasks offer a promising platform for listener-targeted remediation of intelligibility disorders associated with dysarthria. To date, the body of work demonstrating improved understanding of dysarthric speech following a familiarization experience has been carried out on younger adults. The primary purpose of the present study was to examine the intelligibility effects of familiarization in older adults.

Method: Nineteen older adults, with and without hearing loss, completed a familiarization protocol consisting of three phases: pretest, familiarization, and posttest. The older adults' initial intelligibility and intelligibility improvement scores were compared with previously reported data collected from 50 younger adults (Borrie, Lansford, & Barrett, 2017a).

Results: Relative to younger adults, initial intelligibility scores were significantly lower for older adults, although additional analysis revealed that the difference was limited to older adults with hearing loss. Key, however, is that irrespective of hearing status, the older and younger adults achieved comparable intelligibility improvement following familiarization (gain of roughly 20 percentage points).

Conclusion: This study extends previous findings of improved intelligibility of dysarthria following familiarization to a group of listeners who are critical to consider in listener-targeted remediation, namely, aging caregivers and/or spouses of individuals with dysarthria.

Figures

Figure 1.

Group means of intelligibility outcome measures when categorized according to older adults (n = 19) versus younger (n = 50) adults: The panels reflect a significant group difference in initial intelligibility of dysarthric speech (left) but no difference in intelligibility improvement following familiarization with dysarthric speech (right). Error bars delineate ± 1 standard error of the mean (SEM). Younger adult data were from Borrie et al. (2017a).

Figure 2.

Pretest and posttest intelligibility scores, by group, reflect differences in initial intelligibility scores between groups with and without hearing loss but comparable intelligibility improvement scores (slope of connecting line) for all groups.