Scientific American shares (in an interview with facial expression and emotion researcher Ursula Hess, deputy dean at Humboldt University) some of the physiology behind a phenomenon that pro singers know, and the rest of us are learning nowadays – that even if you can’t see someone’s mouth, you know when they’re smiling:
It often helps to smile at others to ease social tensions. Recognizing a smile is much more difficult when the mouth is covered.
You’d think so. But I and my colleagues know from one of our studies, which will be published soon, that this is not the case: People’s ability to recognize emotional expressions does not get worse if their mouth and nose are covered. A real smile does not only move the mouth. Facial muscles—the zygomaticus major and the orbicularis oculi—also contract. The corners of the mouth turn up, and laugh lines appear around the eyes. In the study, observing the area around the eyes was usually enough to recognize someone else’s feelings. We examined this question with scarves, niqabs and masks. Confusion only occurred for certain emotions.Which ones?
Fear and surprise. For both emotions, we usually open our eyes wide. We also rely on the mouth area in a big way. We express fear by widening the mouth. And if we’re surprised, we open it. If the mouth and nose are covered, we cannot see these differences.The fact that we recognize even subtle mental states, such as thoughtfulness, by the changes in expression around the eyes is explained in the Reading the Mind in the Eyes” test developed by British psychologist Simon Baron-Cohen and his colleagues.
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What does a smile sound like?
It sounds bright. This is because the changes in the shape of the mouth alter the modulation of our voices. A serious looking face, on the other hand, sounds darker.Recognizing emotions is one thing. Actually feeling something is another. If we see a person smiling, mirror neurons ensure that we smile, too—at least internally. If we are in a bad mood, that reaction often makes us feel better. Does it also work with a mask?
In research, we call this behavior social mimicry. What it means is that people tend to imitate the behavior of others: if someone sees us cross our legs or put our chin thoughtfully in our hands, the other person often does the same. Through this mirroring of one another, we, as a whole, evaluate an interaction more positively and feel closer to the other person. An individual who doesn’t imitate someone else gives the feeling that something is wrong in the relationship. In the study I already mentioned, study participants imitated the smile of another person even when that individual’s mouth and nose were covered.Masks, however, do not seem to leave a good impression: In Hong Kong, a team studied the effects of wearing masks on the doctor-patient relationship. Patients wearing face masks rated their doctor as less empathetic.
Here we come back to the attitudes that we bring to meeting a person with a face covering. In our studies, participants assessed people with a mask as “colder.” But if someone was wearing a scarf, they were perceived as being comparatively “warmer.” This result is probably linked to the fact that many people still imagine doctors, particularly surgeons, as being distant and having a tendency toward being unemotional. The self-stitched masks that many people now wear are more likely to be perceived like scarves.