Speaker 1: Welcome to brain Stuff production of I Heart Radio, Hey
Speaker 1: brain Stuff, Lauren bob o blam here. The world is
Speaker 1: full of faces. Faces in wall outlets, faces in lamp switches,
Speaker 1: faces in cheese graters. Sometimes these faces have religious significance,
Speaker 1: or like the woman who found an image of the
Speaker 1: Virgin Mary and her grilled cheese, or the cheeto that
Speaker 1: looks convincingly like Jesus. The phenomenon of seeing faces where
Speaker 1: they're not supposed to be, in clouds, on buildings in
Speaker 1: tacos is so common and widespread that it has a
Speaker 1: name paraidolia. In Greek, paraidolia translates as beyond form or image,
Speaker 1: and it means finding meanings or patterns where there aren't any,
Speaker 1: like hearing a heartbeat in white noise, or believing that
Speaker 1: a seat cushion is mad at you. It's easy to
Speaker 1: dismiss paraidolia as at best of fun optical illusion or
Speaker 1: at worst a psychotic delusion. But some scientists now believe
Speaker 1: that our uncanny ability to find faces and everyday objects
Speaker 1: points to a new understanding of how our brains process
Speaker 1: the outside world. Instead of taking in visual cues and
Speaker 1: then making sense of them. As an apple, a tree
Speaker 1: or a face. It might be the other way around.
Speaker 1: What if our brains are actually telling our eyes what
Speaker 1: to see. We spoke with Kang Lee, a professor of
Speaker 1: applied psychology and human development at the University of Toronto.
Speaker 1: Lee has spent decades studying how infants, children and adults
Speaker 1: process faces, and relatedly, he gave a popular Ted talk
Speaker 1: on how to tell kids are lying. Lee explained that
Speaker 1: we're basically programmed to see faces as a product of
Speaker 1: millions of years of evolution. Quote as soon as we're born,
Speaker 1: we start to look for faces. One reason is that
Speaker 1: our ancestors needed to avoid predators or find prey, all
Speaker 1: of which have faces. And a second reason is that
Speaker 1: humans are very social animals. When we interact with each other,
Speaker 1: we need to know if the other person is a
Speaker 1: friend or foe. Since the ability to quickly recognize and
Speaker 1: respond to different faces could be a matter of life
Speaker 1: and death. There's a much higher cost for not seeing
Speaker 1: the lions face in the underbrush than for mistaking an
Speaker 1: orange and black flower for a lion's face. The brain
Speaker 1: is better off making a false positive if it means
Speaker 1: that you're primed to recognize real danger too. Okay, So
Speaker 1: if evolution has programmed our brains to prioritize faces, how
Speaker 1: exactly does it all play out under the hood. The
Speaker 1: conventional understanding of how we see things is that the
Speaker 1: eyes taken visual stimuli from the outside world a light, colors,
Speaker 1: shapes movement, and send that information to the visual cortex,
Speaker 1: located in a region of the brain known as the
Speaker 1: occipital lobe. After the occipital lobe translates the raw data
Speaker 1: into images, those images are sent to the frontal lobe,
Speaker 1: which does the high level processing. We look at a cliff,
Speaker 1: and our brains then have to determine is that a
Speaker 1: rock outcropping or is it a giant head. That conventional
Speaker 1: model is what Lee calls bottom up processing, in which
Speaker 1: the brain's role is to passively take an information and
Speaker 1: make sense of it. If the brain sees faces everywhere,
Speaker 1: it's because the brain is responding to face like stimuli,
Speaker 1: basically any cluster of spots and spaces that roughly look
Speaker 1: like two eyes, a nose, and amount. But Lee and
Speaker 1: other researchers began to question the bottom up of processing model.
Speaker 1: They wondered if it wasn't the other way around, a
Speaker 1: top down process In which the brain is calling the shots.
Speaker 1: Alice said, we wanted to know whether the frontal lobe
Speaker 1: actually plays a very important role in helping us to
Speaker 1: see faces instead of the face imagery coming from the outside.
Speaker 1: The brain generates some kind of expectation from the frontal lobe,
Speaker 1: then goes back to the occipital lobe and finally to
Speaker 1: our eyes, and then we see faces. That question is
Speaker 1: what made Lee think about paradolia. Had read those stories
Speaker 1: of people seeing images of Jesus, Elvis, and angels in
Speaker 1: their toast and tortillas and wondered if he could build
Speaker 1: an experiment around it. So Lee recruited a bunch of
Speaker 1: regular people, hooked them up to an fm R I scanner,
Speaker 1: and showed them a series of grainy images, some of
Speaker 1: which contained hidden faces and some of which were pure noise.
Speaker 1: The participants were told that exactly half of the images
Speaker 1: contained a face, which was not true, and we're asked
Speaker 1: with each new image, do you see a face? As
Speaker 1: a result of this prodding, participants reported seeing a face
Speaker 1: thirty four percent of the time, and there was nothing
Speaker 1: but static. What was most interesting to Lee were the
Speaker 1: images coming back from the real time f m R
Speaker 1: I scan. When part disipants reported seeing a face, the
Speaker 1: face area of their visual cortex lit up even when
Speaker 1: there was no face in the image at all. That
Speaker 1: told Lee then another part of the brain must be
Speaker 1: telling the visual cortex to see a face. In a
Speaker 1: paper provocatively titled seeing Jesus in Toast Neural and Behavioral
Speaker 1: Correlates a Face Paraidolia, Lee and his colleagues reported that
Speaker 1: when the brain was properly primed to see faces, then
Speaker 1: the expectation to see a face was coming from the
Speaker 1: frontal lobe, specifically an area called the inferior frontal gyrus.
Speaker 1: Lee explained, the inferior frontal gyrus is a very interesting area.
Speaker 1: It's related to generating some kind of idea and an
Speaker 1: instructing our visual cortex to see things. If the idea
Speaker 1: is a face, then it would see a face. If
Speaker 1: the idea is Jesus, I'm pretty sure the cortex is
Speaker 1: going to see Jesus. If the idea is Elvis, then
Speaker 1: it's going to see Elvis. The Jesus in Toast paper
Speaker 1: one Lee teen ig Noble Prize, a cheeky award handed
Speaker 1: out by the humorous science magazine Annals of improbable research,
Speaker 1: but Lie says the Paradolia experiment proved the top down
Speaker 1: processing plays a critical role in how we experience the
Speaker 1: world around us. He said, a lot of things we
Speaker 1: see in the world aren't coming from our site, but
Speaker 1: are coming from inside our minds. Lee has also run
Speaker 1: research on babies and racial bias. He found that the
Speaker 1: very youngest babies were able to recognize differences between faces
Speaker 1: of all races, but lost that ability as they grew older.
Speaker 1: By nine months, they could only differentiate between faces that
Speaker 1: were their same race. The rest started to blur together.
Speaker 1: The reason is that they had only been exposed to
Speaker 1: same race faces, in most case mom and dad, for
Speaker 1: the first nine months of their life. From his research,
Speaker 1: Lee now believes that racial biases are not biological. We
Speaker 1: simply learned to trust people that look like the faces
Speaker 1: we saw when our brains were first developing. Unfortunately, this
Speaker 1: can develop later into different kinds of biases based on
Speaker 1: societal messaging and stereotypes. Lee said. The reason that there
Speaker 1: are racial biases is because of early experiences. If we
Speaker 1: created a diverse visual and social experience for children, then
Speaker 1: they would be less likely to have biases. The good
Speaker 1: news is that parents and educators can combat racial bias
Speaker 1: by exposing infants and toddlers to faces of all races
Speaker 1: and identifying them by things like names, professions, or other
Speaker 1: personally identifying qualifiers or interests, not as a white person
Speaker 1: or a black person. Today's episode was written by Dave
Speaker 1: Ruse and produced by Tyler Clain. For more on this
Speaker 1: amounts of other topics, visit how stuff works dot com.
Speaker 1: Brain Stuff is production of iHeart Radio. For more podcasts
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