Impact of clear face masks on audiovisual speech intelligibility and subjective listening effort with normal hearing young adults

Abstract

During the COVID-19 pandemic, facemask use made people suddenly aware of the importance of both visual information and acoustic clarity in speech perception. Masks with transparent panels can provide listeners with visual speech information, but such masks tend to introduce more acoustic distortion than other opaque masks. Thus, their value for improving speech recognition (at least for listeners with normal hearing) is not clear. In the current study we investigated the ability of three different clear face masks to improve speech intelligibility relative to an opaque surgical mask. Normal hearing young adult participants (N = 180) were presented with audiovisual recordings of 150 sentences from a female speaker in 5 different mask conditions (no mask, surgical mask, and three different clear masks) and at three different signal-to-noise ratios (no noise, –5 dB SNR, and −9 dB SNR). After each condition, participants also completed the NASA-TLX survey for subjective effort. Participants also completed an independent lipreading task. Preliminary data suggest decreased subjective effort and improved performance of the clear masks relative to the opaque mask at high SNR. This implies a potential for visual information to make up for decreased acoustic clarity, making clear masks a better choice in difficult listening conditions.