Face masks, speech intelligibility, and listening effort

Abstract

The use of face masks recently has raised awareness about their effects on speech comprehension. In a series of two studies, we assess how different masks speech intelligibility and listening effort. In the first study, we compared four mask types in three noise levels for young and older adult listeners. Stimuli were presented audiovisually. Results showed that, in quiet, speech intelligibility was not greatly affected by any of the masks relative to no-mask conditions. However, in background noise, all masks reduced intelligibility. Masks with transparent windows and cloth masks with filters resulted in the lowest intelligibility scores, while surgical face masks had the least effect. Participants’ subjective effort ratings also reflect that comprehending speech through face masks requires greater effort. Overall, older adults’ listening effort ratings were higher and their intelligibility scores were lower. In the second study, we assess listening effort with pupillometry. We present the same stimuli to a group of young adults in six audio-only conditions: no-mask in quiet, no-mask in moderate noise, and four masks in moderate noise. In addition to intelligibility accuracy and pupil dilation, we also collect subjective effort and performance ratings, pure tone averages, and working memory performance scores.