Communication in Complex Situations: The Combined Influence of Dysarthria and Sensorineural Hearing Loss on Speech Perception in Everyday Noisy Environments

Purpose: Here, we investigated how intelligibility is impacted in underappreciated, highly complex, but real-world communication scenarios involving two clinical populations—when the speaker has dysarthria and the listener has hearing loss, in noisy everyday environments. As a second aim, we examined the potential for modern noise reduction to mitigate the noise burden when listeners with hearing loss are attempting to understand a speaker with dysarthria. Method: Thirteen adults with sensorineural hearing loss (SNHL) listened and transcribed dysarthric speech under three processing conditions: quiet, noise, and noise reduced. The intelligibility scores of listeners with SNHL were compared with previously reported data collected from adults without hearing loss (Borrie et al., 2023). Results: Listeners with SNHL performed significantly poorer than typical-hearing listeners when listening to speech produced by a speaker with dysarthria—an intelligibility disadvantage that was exacerbated when background noise was present. However, it was also found that a time-frequency–based noise reduction technique was able to effectively restore the intelligibility of dysarthric speech in noise to approximate levels in quiet for listeners with hearing loss. Conclusions: The results highlight the substantial intelligibility burden placed upon a communication dyad consisting of a speaker with dysarthria and a listener with hearing loss, when background noise is present. Given the etiologies of dysarthria and hearing loss, and presence of noise in many everyday communication environments, this scenario is not uncommon. As such, these results are an important first step toward understanding the challenges experienced when communication disorders interact. The finding that noise reduction techniques can mitigate much of the noise burden provides a promising future direction for research that seeks to manage communication with two clinical populations.