Some people cannot, for the life of them, remember a face.
The neurologist and writer Oliver Sacks famously wrote about this condition, known as face blindness or prosopagnosia, in his book "The Man Who Mistook His Wife for a Hat."
But there are other people who have an uncanny ability to remember faces, even those of total strangers.
Scientists have studied these "super-recognizers," and found that they are as good at remembering faces as prosopagnosiacs are bad.
Super-recognizers are thought be rare. Josh P. Davis, a senior lecturer of psychology at the University of Greenwich in England, told Yahoo Health that these individuals probably make up less than 1% of the population. He also said that some London police officers are super-recognizers, and use it to identify criminals in blurry CCTV footage.
Davis developed an online test for super-reconizers, and you can take it here. (I scored 12 out of 14, which could qualify me as a super-recognizer, pending further tests.)
A 'creepy' ability
The first case of face blindness was reported in 1976. According to the NIH, it can arise from stroke, traumatic brain injury, or brain diseases, but about 2.5% of the population may be born with this condition, studies suggest.
A Harvard neuroscientist and his colleagues were studying this condition, when they were contacted by a number of people who claimed to have an incredibly good ability to recognize faces.
In 2009, they did a study of four people who were self-proclaimed super-recognizers. The subjects included CS, a 26 year old female PhD student, CL, a 40 year old female homemaker, JJ, a 36 year old female municipal employee, and MR, a 31 year old male computer programmer.
"It doesn't matter how many years pass, if I've seen your face before I will be able to recall it," CS, a 26 year old female PhD student, told the researchers, adding that it only happens with faces.
All four subjects told the researchers about times when they had recognized people who were almost strangers, whom they had not seen for years and had since aged from a child to an adult, or gotten a different hairstyle. They also all claimed to be able to recognize actors who had only minor roles in movies, TV, or ads (for example, Sean Bean, the actor who played Boromir in the Lord of the Rings movies, plays crew supervisor Mitch Henderson in The Martian, below.)
The subjects in the study all said they had to hide their super ability to avoid being creepy.
As CS told the researchers:
"I do have to pretend that I don’t remember [people], however, because it seems like I stalk them, or that they mean more to me than they do when I recall that we saw each other once walking on campus four years ago in front of the quad!"
Memorable faces
In the study, Richard Russell of Harvard and his colleagues designed tests to measure extreme face recognition ability.
The first test involved showing people pictures of famous people before they were famous, often as children, and the subjects had to name or identify them.
But how well they performed on the famous face test could be affected by whether they had seen these famous people before. So the researchers designed a second test, which involved learning new faces.
They adapted something known as the Cambridge Face Memory Test, which involves showing people six unfamiliar male faces from three different views, and then asking them to pick that face out of three choices. It starts out easy and gets progressively more difficult, as the faces are shown from different angles, lighting conditions, and with added graininess.
To make the test harder, the researchers made a long form of the test by adding a fourth section, which was much more difficult than the short form.
They gave versions of these tests to the four super-recognizers as well as 25 regular people as controls. The super-recognizers performed above and beyond everyone else on both tests (with the exception of one subject, who was not given the long-form memory test).
On the short-form test, three of the super-recognizers received perfect scores, and the fourth made only one error. On both the short and long versions, they scored better than any of the controls.
The super-recognizers also scored better than the controls on the famous person test, except for one other subject, who scored the same as one of them.
Taken together, the findings provide "objective evidence in support of [the super-recognizers'] subjective experience of having significantly better than normal face recognition ability," the researchers wrote in the study.
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