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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.