Effects of face masks on the appearance of emotional expressions and invariant characteristics

Abstract

Faces convey a lot of information about a person. However, the usage of face masks occludes important parts of the face. There is already information that face masks alter the processing of variable characteristics such as emotional expressions and the identity of a person. To investigate whether masks influenced the processing of facial information, we compared ratings of full faces and those covered by face masks. 196 participants completed one of two parallel versions of the experiment. The data demonstrated varying effects of face masks on various characteristics. First, we showed that the perceived intensity of emotional expressions was reduced when the face was covered by face masks. This can be regarded as conceptual replication and extension of the impairing effects of face masks on the recognition of emotional expressions. Next, by analyzing valence and arousal ratings, the data illustrated that emotional expressions were regressed toward neutrality for masked faces relative to no-masked faces. This effect was grossly pronounced for happy facial expressions, less for neutral expressions, and absent for sad expressions. The sex of masked faces was also less accurately identified. Finally, masked faces looked older and less attractive. Post hoc correlational analyses revealed correlation coefficient differences between no-masked and masked faces. The differences occurred in some characteristic pairs (e.g., Age and Attractiveness, Age and Trustworthiness) but not in others. This suggested that the ratings for some characteristics could be influenced by the presence of face masks. Similarly, the ratings of some characteristics could also be influenced by other characteristics, irrespective of face masks. We speculate that the amount of information available on a face could drive our perception of others during social communication. Future directions for research were discussed.

Keywords

• face masks
• face recognition
• emotion recognition
• emotional expressions