Transparent face masks’ dual benefit over surgical face masks

The use of transparent face masks may be better than surgical face masks, say researchers from Japan. While face masks have been effective at controlling the spread of the coronavirus, they also conceal much of the face, making it hard to communicate and interact as we once did. Instead, transparent face masks can allow for the perception of facial expressions and simultaneously suppress aerial dispersion of infectious substances.

A vast majority of studies on the effects of face masks on perceptions on facial expressions have been conducted on populations based in Western countries – the cues used for comprehending facial expressions differ from East to West, so researchers led by Professor Jun Kawahara at Hokkaido University and Associate Professor Yuki Miyazaki at Fukuyama University wished to see if the findings from the West could be applied to the East.

The researchers conducted two separate experiments using database-sourced images of female faces and male faces, expressing a range of expressions. The images were manipulated so that each image was available in three versions: without a mask, with a surgical mask, and with a transparent mask. Volunteers viewed a random series of images, one at a time, and were asked to determine the facial expression in each image.

Surgical masks were found to disrupt the perception of facial expressions and made these expressions harder to recognise – the ability to distinguish fear and happiness were the most affected, with happy faces being primarily misclassified as neutral, and fearful faces being misclassified as angry or surprised.

However, in both experiments, the use of transparent masks did not cause any negative effect on perception of facial expressions. In both experiments, the perception of facial emotion was not influenced by the sex of the participants or the face models.

The researchers thus conclude that transparent face masks, which suppress respiratory droplets that spread the deadly SARS-CoV-2 virus, do not occlude facial expressions.