Masks make it harder to recognize each other and read each other's facial expressions, a Brock University researcher says. And that's a task that's already hard at the best of times.
Catherine Mondloch is a professor and director of Brock's face perception lab, which studies how people recognize strangers.
While masks have brought some attention to how complicated it is to recognize each other, she said, people still overestimate their abilities and tend to have false confidence.
"Because we're really good at recognizing our family and our neighbours and actors — you have to be able to recognize actors if you're going to track a plot of a movie — we just have this feeling or assumption that we're good at recognizing all faces," she said.
While it makes "perfect sense" that wearing a mask makes this recognizing people harder, she said, the reality is people only realize they're making a mistake if it involves a friend, neighbour or family member — not a stranger.
Workers check ID, look for signs of distress
In fact, Mondloch said, emerging research suggests masks have an even stronger effect on distorting or concealing unfamiliar faces.
People are tasked with recognizing strangers and their emotions every day, she said, and there can be serious implications if someone gets something wrong.
Cashiers at liquor stores need to match the person buying alcohol with their photo ID. Health-care workers have to notice signs of distress on an emergency call.
"It's actually really challenging. So masks have, I think, done a bit of a favour in making us aware of how difficult that is," she said.
The ability to recognize faces also varies widely, she said, from "super recognizers" to those who already struggle with perception.
Adding a mask exacerbates the issue, but even makeup, hairstyles, and lighting — which don't have significant influence if you know someone well — can make someone think a stranger is actually two different people, she said.
"If we knew that, we'd probably do something different with our photo ID [systems]," she said, adding the world heavily relies on this process.
While face coverings aren't the only object to partially conceal faces — people sport sunglasses or bundle up in warm, winter scarves — research has found masks have had a more profound effect.
Mondloch said a study in the U.K. had people guess the emotions others portrayed in photographs. Participants made mistakes when the person in the photo was wearing sunglasses, but even more when that face had a mask.
She noted the expressions were strong, and not just subtle like the furrow of a brow.
"What this study shows is those emotional cues are really much harder to pick up on, even when they're intense, if a face has a mask," she said.
Since people use subtle cues in a fraction of a second to decide whether someone is trustworthy or not, she said, masks will also impact first impressions, which are largely inaccurate to begin with.
Mondloch referenced a healthcare study, where people's first impressions of distress influenced how they were prioritized when arriving in emergency. If people can't see "distress," she said, then that's going to affect judgments.
"I think any time you're working in a setting where you need to read cues, it's important to just be mindful that somebody might appear aloof, but actually you're just unable to see how they're feeling," she said.
While people can attempt to help by showing their feelings more "dramatically," Mondloch said, that can be an exhausting process and "you can only keep that up for so long."
Kids with 'cuter' faces get benefit of the doubt
But for people whose faces tend to appear angrier, she said, facial coverings can be blessing.
Mondloch says her lab is starting to question how an adult's perceptions of children change when a mask is added to the mix.
Her research has found that adults give children the benefit of the doubt if they have a face that looks high in trustworthiness. Mondloch wonders if masks make that benefit disappear.
Faces that are "cute," resemble happiness or are more "baby-faced" tend to be judged as more trustworthy, she said.
"These first impressions aren't accurate," she said. "But the children who look trustworthy get away with things...and then these poor kids with a low-trust face get a very different response."
Studies have also yet to look into how masks impact "unexpected faces" — such as picking someone out in a crowd —and the impact on different age groups, such as older adults.
"We take this ability to recognize people for granted," she said.
"I think people are suddenly more aware of how much we rely on faces for daily life."