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If you are one of those people who has trouble remembering faces, you can blame your parents. And if you never forget a face, you can thank them.
NPR's Jon Hamilton reports on new research that finds people inherit their ability to recognize faces.
JON HAMILTON: People are wired to pay attention to faces pretty much from birth. Jeremy Wilmer, a psychologist at Wellesley College, says that's clear from experiments that put things like a circle, a square and a drawing of a face in front of a baby who is only a few days old.
Professor JEREMY WILMER (Psychology Department, Wellesley College): A baby will spend a lot of time looking at the face relative to the other things. In fact, if you give a baby a right-side up face and an upside down face, it will prefer the right-side up face.
HAMILTON: But this early interest in faces doesn't necessarily mean we're good at remembering them when we grow up. Wilmer says some people struggle to recognize faces while other people qualify as super recognizers.
Prof. WILMER: I have a very good friend. She's a school teacher who often will refrain from saying hello, Jon, because she might have only met them six years ago on the subway, and she likes to avoid creeping people out.
HAMILTON: Wilmer and his colleagues wanted to know to what extent the ability to recognize faces is influenced by our genes. So he compared hundreds of fraternal twins who share only half their genes with hundreds of identical twins who share all their genes.
All the twins took a test that involves memorizing six faces. Then, participants are shown three more faces: Two unfamiliar and one from the group they've memorized.
Prof. WILMER: Then they have to say, which one of these three is one of the ones I was supposed to remember?
HAMILTON: Wilmer says the ability of a pair of non-identical twins to recognize faces often differed quite a bit, but that wasn't the case with twins who were identical.
Prof. WILMER: We found that identical twins are extraordinarily similar to each other, evidence that face recognition ability is a highly familial trait.
HAMILTON: Wilmer's team also wanted to know whether recognizing faces was a separate skill or just an aspect of a broader ability to remember things. So they tested several thousand people via an Internet site, on a range of recognition and memory skills.
Prof. WILMER: Those who were good at face recognition ability were not necessarily good at verbal ability and were not necessarily good at abstract art memory.
HAMILTON: All of this supports the idea that there is some part of the brain that specializes in processing faces.
Nancy Kanwisher, a brain scientist at MIT, says the most likely candidate is a place her lab has named the fusiform face area.
Professor NANCY KANWISHER (Department of Brain and Cognitive Sciences, MIT): Just behind and underneath, and in a bit from your right ear.
HAMILTON: Kanwisher says it makes sense that genes would include special code for such an area, because faces are so important to us.
Prof. KANWISHER: They tell you not just who that person is but what kind of mood they're in, whether they're male or female, how old they are, you know, what they're looking at - are they looking at you or something else? All this rich visual information you can get from a brief glimpse at a face.
HAMILTON: Kanwisher says face recognition appears to be so basic that people don't even need to learn it the way we learn language. Kanwisher says Japanese researchers provided strong evidence of this in an experiment with monkeys.
The researchers spent years raising monkeys who never saw faces, human or monkey. The animals were separated from other monkeys, and their human caretakers wore masks.
Even so, Kanwisher says...
Prof. KANWISHER: These monkeys had adult-like face discrimination abilities on the very first session that they were ever tested on faces.
HAMILTON: Probably thanks to their genes.
Wilmer's study appears in the Proceedings of the National Academy of Sciences.
Jon Hamilton, NPR News. Transcript provided by NPR, Copyright NPR.
People who struggle to remember faces can blame their parents. The ability to remember a face is inherited, according to a paper in the Proceedings of the National Academy of Sciences.
People who struggle to remember faces can blame their parents.
That's because the ability to remember a face is inherited, according to a paper in the Proceedings of the National Academy of Sciences. Researchers also found that people who are good at remembering faces are not necessarily good at other memory tasks.
Taken together, these results strongly support the idea that face recognition ability comes from a dedicated circuit, or set of circuits, in the brain.
Identical Twins, Nearly Identical Ability To Remember
The paper, which comes from an international team, included two different studies.
The first looked at nearly 300 pairs of twins. Some were identical, meaning they share all their genes; others were nonidentical twins, who share only half their genes.
All the twins took a test that involved memorizing six faces. Then, participants were shown three more faces and were asked to identify the one face in this group they had seen before.
The face recognition ability of pairs of nonidentical twins often differed quite a bit, says Jeremy Wilmer, the study's lead author and a psychologist at Wellesley College in Massachusetts.
But that wasn't the case with pairs of identical twins, whose performance was "extraordinarily similar," Wilmer says.
These results offer strong evidence that "face recognition ability is a highly familial trait," Wilmer says.
Using A Special Part Of The Brain
The second study used a Web site to test the ability of several thousand people to remember faces, word pairs and abstract art images. The study found no link between face recognition ability and scores on the other tasks.
All of this supports the idea that there is a part of the brain that specializes in processing faces, says Nancy Kanwisher, a brain scientist at MIT.
The most likely candidate is the "fusiform face area," which is located "just behind and underneath, and a bit from your right ear," Kanwisher says.
She says it makes sense that our genes would include special code for such an area, because faces are so important to humans and some other primates.
Faces tell us whether we know a person, what mood they're in, how old they are, and whether they are looking at us or something else, Kanwisher says. "All this rich visual information you can get from a brief glimpse of a face."
Face recognition appears to be so basic, she says, that it is actually hard-wired into the brain.
Similar Findings In Monkeys
Japanese researchers provided strong evidence of this in an experiment with monkeys a couple of years ago, Kanwisher says.
The researchers spent years raising monkeys who never saw a face — human or monkey. The animals were separated from other monkeys, and their human caretakers wore masks.
Even so, when the monkeys were tested, they had "adult-like face discrimination abilities," Kanwisher says, adding that this is probably because the ability to recognize faces is carried in our genes and present from birth.
The finding in monkeys is consistent with experiments on human babies just a few days old, Wilmer says.
When a baby is presented with representations of things like a circle or square and a face, Wilmer says, "The baby will spend a lot of time looking at the face relative to the other things."