Wearing Face Masks Strongly Confuses Counterparts in Reading Emotions

Abstract

Wearing face masks is one of the essential means to prevent the transmission of certain respiratory diseases such as coronavirus disease 2019 (COVID-19). Although acceptance of such masks is increasing in the Western hemisphere, many people feel that social interaction is affected by wearing a mask. In the present experiment, we tested the impact of face masks on the readability of emotions. The participants (N = 41, calculated by an a priori power test; random sample; healthy persons of different ages, 18-87 years) assessed the emotional expressions displayed by 12 different faces. Each face was randomly presented with six different expressions (angry, disgusted, fearful, happy, neutral, and sad) while being fully visible or partly covered by a face mask. Lower accuracy and lower confidence in one's own assessment of the displayed emotions indicate that emotional reading was strongly irritated by the presence of a mask. We further detected specific confusion patterns, mostly pronounced in the case of misinterpreting disgusted faces as being angry plus assessing many other emotions (e.g., happy, sad, and angry) as neutral. We discuss compensatory actions that can keep social interaction effective (e.g., body language, gesture, and verbal communication), even when relevant visual information is crucially reduced.

Keywords: COVID-19; accuracy; confusion; emotion; face masks; mouth; pandemic.

Figure 1

A person showing six different emotions without a mask (A) and wearing a mask (B). Original material from top row stems from MPI FACES database (Ebner et al., 2010).

Figure 2

Mean percentage of correct assessment of the emotional states for faces with masks (blue) or without masks (red) on the face. Error bars indicate confidence intervals CI-95% based on adjusted values for taking within-subject variances into account (Morey, 2008). Asterisks indicate statistical differences between conditions of wearing and non-wearing on the basis of paired t-tests: ^****p < 0.0001; ns, not significant.

Figure 3

Mean percentage of correctly assessing the emotional states with masks (blue) or without masks (red) on the face, split by face sex and face age group. Error bars indicate confidence intervals CI-95% based on adjusted values for taking within-subject variances into account (Morey, 2008). Asterisks indicate statistical differences between conditions of wearing and non-wearing on basis of paired t-tests: ^*p < 0.05, ^**p < 0.01, ^***p < 0.001, ^****p < 0.0001; ns, not significant.

Figure 4

Mean confidence of assessing the emotional states (for correct classifications) with masks (blue) or without masks (red) on the face. Error bars indicate confidence intervals CI-95% based on adjusted values for taking within-subject variances into account (Morey, 2008). Asterisks indicate statistical differences between conditions of wearing and non-wearing on basis of paired t-tests: ^*p < 0.05, ^****p < 0.0001; ns, not significant.

Figure 5

Confusion matrix of expressed and perceived emotions. Top matrix: faces without masks, bottom matrix: faces with a mask. Percentages compile up to 100% for each expressed emotion. The deeper blue the cell, the higher the score of this cell.