Are you a super-recogniser? The science of superior facial processing

Super recognisers have excellent face recognition, and can identify unfamiliar faces after a brief glimpse. Photo / 123rf

Researchers are studying super-recognisers to understand how we recognise faces and how this ability can be improved.

Do you remember the face of any stranger who passed by you today?

You probably can’t, but super-recognisers can. These rare individuals can identify unfamiliar faces after a brief glimpse. And by studying them, researchers hope to understand how we recognise that a face belongs to someone we know - an important ability for a social species such as ours.

“The face is the most important visual stimulus for humans in their environment, probably throughout evolution,” said David White, associate professor of psychology and lead investigator of the Face Research Lab at the University of New South Wales, Sydney. “We’re a social species, and the information contained in the face is vital to behave rationally in a social environment.”

We don’t, for example, usually need to identify specific chairs, because knowing “it’s just a chair” is enough, said Meike Ramon, an assistant professor and head of the Applied Face Cognition Lab at the University of Lausanne. “But for faces, it matters who each unique face belongs to.

Face processing on a spectrum

Our ability to recognise faces is part of a spectrum.

At one end are the 2 to 3% of people with face blindness - or developmental prosopagnosia - who have trouble recognising faces that should be familiar to them, including those of loved ones or even their own.

At the other end are super-recognisers, first reported on in 2009, who excel at identifying or matching faces, even those that are unfamiliar to them - whether they are flipped upside-down, low resolution or presented at a different angle.

They have a “unique ability to derive a three-dimensional representation of a face, even when they see only one 2D image of the person,” Ramon said. Super-recognisers are rare, though how rare is hard to estimate because there is no single agreed-upon method for categorising them.

Most people’s ability to process faces lies somewhere in between, where recognising familiar faces is easy but deciphering unfamiliar ones is challenging.

Super-recognisers can remember a stranger’s face after just a brief glimpse. Photo / 123RF

What makes super-recognisers super

Super-recognisers are drawn to faces.

Even when they are presented with random pictures of everyday life, super-recognisers spend more time looking at faces, Ramon and her colleagues reported in one 2022 study.

Their eyes are also drawn immediately to the face, regardless of where that face is in the photo - and most closely near the optimal place for identification, below the eyes.

“It seems like faces are extremely salient for super-recognisers for reasons that we still don’t know,” Ramon said.

Their brains also respond differently to visual images less than a second after seeing them.

In a 2024 study, Ramon and her colleagues recorded brain activity from 16 super-recognisers and 17 control participants using EEG while they viewed a variety of pictures, such as of plants, animals, scenes and faces. Even just 65 milliseconds after an image pops up - faster than the blink of an eye - their brains already start responding differently from neurotypical brains.

Interestingly, super-recognisers exhibited this difference in neural activity regardless of what they were looking at, which suggests that their brains process visual information differently in general.

Other research suggests that super-recognisers have broader activation of the brain’s face-processing networks, even when looking at unfamiliar faces.

The super-recogniser ability to process faces may simply reflect how good they are at processing all visual information. And conversely, people with face blindness not only struggle with faces but may also have difficulties processing other types of visual information.

Curiously, however, super-recogniser abilities may extend beyond the visual domain. A 2021 study of 529 participants reported that super-recognisers were also much better at identifying unfamiliar and familiar voices, despite having merely average pitch discrimination, which may point to a “common basis for person identity processing abilities” across different senses, White said.

Still, super-recognisers have weaknesses. Just like typical recognisers, super-recognisers also find it more difficult to distinguish between the faces of people of ethnicities different from their own.

Super-recognisers focus naturally below the eyes for identification clues. Photo / 123RF

Getting better at recognising faces

Identifying unfamiliar faces is tricky, even for experienced professionals such as forensics examiners and customs agents. Unfortunately, it is not possible to train people to become super-recognisers, which appears to be a natural ability.

When White and his colleagues pit super-recognisers against trained forensic examiners, the differences in their process for face identification were clear, though they achieved equivalent accuracy.

Super-recognisers were more intuitive and made their judgments quicker with great accuracy after just 2 seconds. They looked at faces more, but there was no clear pattern in where they were looking, the 2023 study reported.

Forensic examiners, by contrast, were much more methodical and systematic. They took longer to make their decisions, requiring up to 30 seconds, but picked up on facial clues that most people would not pay attention to.

“What super-recognisers are doing is more of a black box,” White said. “It’s more of an automatic processing.”

The growing recognition of super-recognisers has increased interest in using their powers to aid policing and security work, though there appears to be no formal, systematic approach for identifying and deploying them. Ramon has worked with Berlin Police and White has worked with the New South Wales Police Force to identify super-recognisers.

But super-recognisers aren’t perfect, White said.

In White’s research, when super-recognisers and professionals made errors, super-recognisers maintained a high confidence, while professionals were less confident.

So far, lessons on how to improve our facial processing come from trained experts.

In a 2021 study, White and his colleagues taught novice participants some of the tricks used by professional examiners, such as focusing on the ears, scars, freckles and blemishes. After just a six-minute training, the novices got somewhat better - an improvement of 6% in accuracy.

But more research on super-recognisers could help solve the mystery of how an unfamiliar face becomes a recognisable and familiar face. The fact that super-recognisers are able to do so well with unfamiliar faces may give us clues in how the brain makes that change, White said.