If some people can hardly recognize faces at all, are there others who are incredible face detectors?
Richard Russell thinks so.
Dr. Russell is a psychology professor at Gettysburg College. When he was at Harvard University, he was the lead author of a study last year titled, "Super-recognizers: People with extraordinary face recognition ability."
The study looked at four people whose capacity to recognize different faces and remember them was far above average.
They were so good, in fact, that Dr. Russell and his team had to develop new tests to measure their proficiency because the standard tests were too easy.
One of the exams he came up with is called Before They Were Famous, in which he assembled 56 photos of celebrities at younger ages, before they were well known, and asked people to identify them.
Even the super-recognizers identified only about half the photos correctly, he said, but a control group of typical people got only a quarter of them right.
Celebrity images are actually a good marker of face recognition skill, he said.
People with prosopagnosia, or face blindness, "generally don't watch a lot of television or movies because they can't keep the characters straight, so they often don't know a lot of celebrities or politicians," he said.
"Super-recognizers are kind of the opposite, where they recognize not just the stars but the extras who have only a couple lines, and part of that has to do with practicing something you're already good at."
Jennifer Jarett, one of Dr. Russell's super-recognizers, certainly fits that description.
Growing up near Philadelphia, she was always the one in her family who not only could identify a TV actor with a minor role, but say what commercial he had appeared in the year before.
But it wasn't until she went off to college at the University of Pennsylvania that she realized just how differently she saw the world.
Like other students, she met new people every day. Unlike her friends, she remembered the faces of almost every one of them.
"So later, if we'd be at a party, a friend might introduce me to someone and say, 'Do you know this person?' and I'd say, 'Yes,' and the person would say 'No, we don't know each other.'
"And then I'd say, 'Don't you remember a few weeks ago I was walking to biology and you were walking to English and you asked my friend a question about a quiz and then you walked on?' and she'd just give me this totally weird look.
"I learned I had to be careful because it made people really uncomfortable."
From experiences like that, Ms. Jarett, 39, who now works as an investigator for a New York City agency, began to realize she was much better at recognizing faces than most people she knew.
She contacted Dr. Russell after reading a newspaper article about his prosopagnosia research.
And while it was nice for his tests to confirm what she had always suspected, her preternatural facility with faces still bemuses her.
"It's not something like this exciting superpower I have," she said. "It's not even something I'm trying to do."
She has learned not to tell everyone she recognizes that she has met them before. Sometimes, she says, that creeps people out.
A case in point: One day recently she got on the subway, and a woman sat down across from her.
"I knew right away that this woman had been in a sorority with me at Penn 20 years ago. But I waited to see if she would recognize me.
"And when she didn't, I didn't say anything."
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