In many places all over the world, a mask has become mandatory to slow down the spread of SARS-CoV-2. People wear one on the bus or train, during shopping trips or at doctor’s appointments. How does that practice change basic communication? Does a face covering impair social interaction? Facial expression and emotion researcher Ursula Hess, deputy dean for international affairs at the faculty of life sciences at Humboldt University of Berlin, provides some answers in this interview with Scientific American’s German-language sister publication Spektrum der Wissenschaft.

[An edited transcript of the conversation follows.]

If you wear a mask correctly, you cover your nose and mouth—half of your face becomes unrecognizable. How does that affect the perception of someone looking at you?
Whether the person with a mask makes a positive or negative impression depends mainly on what you think about mask wearing. If you’re someone who thinks that the current protective measures go too far, a person with a mask may appear gullible, if not downright foolish. On the other hand, if you are a devoted mask wearer, you will probably be more sympathetic to the other person.

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.

That test has been used to diagnose autism spectrum disorder, right?
Exactly. Because people with autism may find it harder to empathize with other people and may avoid eye contact, the test subjects are asked to look at pictures of different areas around the eyes and to assign them the correct emotional states. People without autism do very well on this test. 

The supermarket checkout is not a laboratory. Can such experiments be applied to everyday life?
Our studies show that we do not rely on seeing the mouth of the person we are communicating with to recognize emotion. There is even a distinct advantage in encounters at the supermarket checkout, at the bakery or on the street: people meet with their whole bodies. After all, whether a person is sad, angry or happy is expressed not only through facial expressions but also through the way they move and talk. And you can hear whether someone smiles or looks serious.

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.

What effect does wearing masks have on children? After all, they do not yet grasp emotions as well as adults.
Children of primary school age are hardly less able than adults to recognize emotions. For toddlers, the sight of bodies and faces that somehow look different is unfamiliar and therefore can be stressful. Many babies cry when they see a bearded person for the first time. If the nose, mouth and chin of someone they are looking at is suddenly gone, they may be upset.

What can parents do?
They can familiarize their children with the mask in a playful way— for example, by holding the mask in front of their face for a short time and then taking it off again. Toddlers learn quickly and will get used to the new situation. It is different for people who have difficulty hearing. They are often dependent on reading lips. So the current situation is a challenge. Some initiatives are underway to produce masks that are transparent around the mouth. It remains to be seen whether they will become generally accepted, however.

Can we improve our social interactions with masks?
Yes, by using them as a sign of solidarity. If we see a face covering as an expression of mutual consideration for others, it can bring us all together. This reaction creates a sense of community and perhaps gives us back a bit of the sense of well-being that may have been somewhat lost because of this extraordinary situation.

This article originally appeared in Spektrum der Wissenschaft and was reproduced with permission.

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