- Face blindness is a disorder that prevents you from recognizing familiar faces
- Some estimate that two per cent of people have it, but a new study suggests it’s more
- Try the King’s College London quiz to see if you’re one of them
Many of us have trouble remembering names, but can still identify a former co-worker or former flame when they pop up on social media.
However, a new study from Harvard University found that up to 5.42% of people struggle with the opposite problem.
“Prosopagnosia,” or face blindness, is a disorder that prevents you from recognizing faces you have seen before, including those of friends and family.
It can also prevent you from identifying yourself in photos or in the mirror, or make you feel like you know complete strangers.
Last year, Brad Pitt detailed his experience with the disease, admitting “no one believes him” when he talks about it.
Nursery nurse Hannah Read, who has the UK’s worst case of face blindness, said ‘every face looks the same’ and is just ‘two eyes, one nose and one mouth’.
People with this disorder may cope by using other ways to recognize people, such as remembering the way they walk, their hairstyle, their voice, or their clothes.
It is thought to be the result of abnormalities, damage or impairment of the right fusiform gyrus – a fold in the brain that appears to coordinate facial perception and memory.
Prosopagnosia can result from stroke, traumatic brain injury, or certain neurodegenerative diseases, but in some cases it is present at birth.
It seems to run in families, making it likely the result of a genetic mutation or deletion.
While it’s commonly cited that between 2 and 2.5% of the world’s population suffers from some form of face blindness, researchers set out to determine its true prevalence in a new study published in the Diagnostic and Statistical Manual of mental disorders.
They recruited 3,341 people to complete three different online surveys, the first asking them to describe their own experiences of face recognition in their daily lives.
The next two were then objective tests that probed their ability to learn new faces and recognize famous faces, respectively.
The results showed that 31 people had a severe form of prosopagnosia, while 72 had a mild form – a total of three percent of study participants.
They also found that participants who could easily recognize faces and those who could not were not obviously distinguishable.
Instead, most of them fell somewhere on a spectrum of severity and presentation, similar to other developmental disorders like autism and Alzheimer’s disease.
The researchers then used different diagnostic criteria to assess some of the participants with face blindness.
Depending on their degree of rigor, they identified affected prosopagnosia between 0.13 and 5.42% of the group.
Interestingly, it was also found that the strictest criteria did not always identify those with the lowest ability to recognize faces.
As a result, they concluded that scientists studying the disorder should relax their diagnostic threshold and divide people into “mild” or “major” cases.
The diagnostic criteria for face blindness vary, but researchers at King’s College London have created a short questionnaire for people who think they may have it.
He asks people how much they agree with phrases like “I often mistake people I’ve met for strangers” or “I sometimes have trouble following movies because of difficulty recognizing characters”.
Other questions include: “When I was in school, I had trouble recognizing my classmates” or “When people change their hairstyles or wear hats, I have trouble recognizing them” .
Each question is scored out of five, giving a total score of up to 100. This final score could be used to help determine the severity of face blindness.