This article originally appeared on Tonic.
The first doll-centric horror plot I saw was an episode of the Twilight Zone where “Talky Tina," a girl doll with bow-tied pigtails, terrorizes and murders its owner’s stepfather. I remember eyeing my own toys suspiciously afterwards, and feeling grateful I had mostly bears, rather than porcelain imitations of little children.
Countless movies and TV shows have capitalized on a similar premise: Dolls are creepy AF. The more human they look—with moving glass eyes, realistic hair, or a slight blush on the cheek— the more they weird us out.
But why do we find them so creepy? According to Thalia Wheatley, a cognitive neuroscientist at Dartmouth University, it’s related to the way our brains detect and pay attention to faces. She's been using our responses to dolls to investigate a simple skill we all have, but a lingering mystery in neuroscience: How exactly do we tell a who from a what? And what can a doll's creepiness tell us about that process?
It begins with how we see faces at all, she says. We pay special attention to them, and have done so since we were babies. Studies have found that newborns will pay more attention to faces than to faces whose features have been scrambled. It’s also been established that the brain shows activity in specific regions to any face in just 170 milliseconds, so we notice them really fast. In this rapid face recognition, our brains are not very picky. Two circles and a curve will elicit the same face response as a human's face, and this is why we sometimes see faces in inanimate objects, like power outlets, or a colon and a parenthesis :) .
But if that were as far as our facial recognition capabilities went, we’d walk around in the world pretty confused. “We must be able to discriminate faces worthy of our thoughts, feelings, and actions from false alarms that are not actually faces,” Wheatley wrote in a recent paper. “Otherwise we might regard clouds, cars, or houses as objects with a mental life.” The way our brains know the difference between a who and a what lies in our ability not only to see faces, but to know whether a face has a mind attached to it. Enter the dolls.
In 2010, Wheatley showed Dartmouth students a series of images morphing from a doll to a human baby, with many in-betweens. “We knew that one endpoint was a doll, and the other endpoint was a human being,” she says. “The question was whether there’d be any consistency in when people determined it slipped from one to the other.”
What they found was that people are very specific about where that spot was. It wasn’t at the halfway point; our standards for humanness are higher. People felt the image was alive at around 65 to 67 percent human. "The same tipping point occurred whether people were asked if the face 'had a mind', 'could form a plan,' or was 'able to experience pain,' indicating that recognizing life in a face is tantamount to recognizing the capacity for a mental life," Wheatley says. When Wheatley asked certain participants why they felt that way, one person said that’s when the doll "started to look back at me."
In a follow-up study, Wheatley used EEG to measure the brain responses of people looking at doll faces, human faces, and the face of a clock. She found that they way the brain perceives faces has two stages. The first we already knew: that a face is rapidly detected. But there's another, longer process where our brains try to determine if a face has a mind. If the brain decides that face does, your attention stays with the face. If you deem something not to have a mind, then your attention wanes.
Wheatley thinks the first part is very primitive, which is why even newborns show the ability to do it. “That needs to be rapid because at that point it’s about survival to detect possible faces very quickly,” she says. But the second stage moves beyond survival. “You’re basically looking to see whether this person has a mind you can connect with. Is somebody home?”
And that’s where the creepiness can come in. With dolls, or other human-like objects that do a better job at mimicking what real faces look like, your brain is searching for a mind and not finding one. But it's getting a lot of the same cues (eyes, mouth, expressions) that it would receive in faces with minds. “There are these signals that are telling our brain this thing is alive,” she says. “But we know it’s not alive. And that juxtaposition is really creepy.”
This is called by some researchers the uncanny valley, or a “dip in emotional response that happens when we encounter an entity that is almost, but not quite, human,” Stephanie Lay, a psychologist who studies the uncanny valley, wrote in The Conversation. The uncanny valley theory dates back to 1970, from Japanese roboticist Masahiro Mori, and is considered a major hurdle for the integration of human-like robots or androids into our societies.
Lay's research has shown we feel uncomfortable when we see expressions on dolls, avatars, or robots that we would never encounter in nature. “The things that I found triggered that sense of unease most strongly, were those faces where you’ve got an expression in the mouth and the eyes that were incongruent. They didn’t tie up together,” she says. “The creepiest ones were when you have a happy smiling mouth, and eyes that are angry or frightened.”
Angela Tinwell, a senior lecturer at the School of Games at the University of Bolton, started to study the uncanny valley after seeing her students struggle to make three-dimensional virtual characters in video games. Similar to Lay and Wheatley's work, she's found that incongruences in eyes, facial expressions, or body language can lead to avatars looking eerie, instead of human like.
Wheatley says it's still an open question as to when all these processes develop. Little kids don't seem to be as creeped out by dolls as adults are, and this could be because they're not yet considering that other people and objects could have minds. Studies on the effect of the uncanny valley on children might reveal more about what age that kicks in, one from last year finding it in children ages nine and up, but not younger.
But the end goal isn't only to make avatars or robots that don't make us squirm. Understanding more about the detection of faces and minds could reveal some nuances in the way we see each other too. After Wheatley's work was published, Jay Van Bavel, a social neuroscientist at NYU used similar doll-to-people morphing, to ask how social factors could influence mind detection.
He's been finding that social alliances can impact how easily you see a mind. People will be quicker to see a mind in the face of someone in their group, whatever that group may be. For example, in the 2015 Super Bowl his lab found that football fans didn’t require as much “humanness” to see a mind in their favorite quarterback’s face. For the quarterback of the other team, they needed more humanness for to see a mind.
His lab is currently exploring how this effect could cause people to treat others in everyday life. In medical treatment, for example, they’re investigating how practitioners could have a harder time detecting expressions of pain in the faces of African American men to try and explain a contributing factor in the racial disparities of pain management.
“This might have implications for the dehumanization of out group members,” Van Bavel tells me. “Throughout history, people have treated certain groups as less than human. In most cases of genocide, from Nazi Germany to Rwanda, the minority group was compared to vermin (e.g., rats or cockroaches). By seeing these groups as less than human, it allows people to commit terrible atrocities against them."
I ask Tinwell if she thinks the uncanny valley will ever go away, as our dolls, video games, and robots get more realistic. And could that affect the way we see minds in people too? She thinks that even though face and mind representations will get better, our brains will only become more discerning as viewers. “I think we’ll always stay one step ahead of virtual technology and dolls and animation,” she says.
Lay agrees, but says that while our brains will never evolve to think that robots have minds, we will probably grow to think of them as less creepy. As a researcher studying the uncanny, she’s found her threshold for creepiness has changed. “We’ll become habituated,” she says.
And what about dolls? In a potential future with human-like robot concierges or assistants, will there stop being scary movies made about dolls? Probably not, Lay says, because they still hover in a strange place in the boundary between human and non-human.
“I think it’s only embodied androids where we’ll become more tolerant,” she says. “The qualities that dolls have are subtly different because they’re static representations of human babies. I think there is something inherently creepy about this stillness."
Also, we might enjoy it—just a little. Wheatley thinks that since dolls live so closely to the boundary, it can be scary, but in a way that's fun; why horror movies are exciting but don't cause us any lasting distress. "We like suspending that disbelief at times," she says. "When it’s safe to do so. It’s thrilling to see Chuckie the clown, to let our brain play with that ambiguity. But if there was actually a clown doll that walked into your house, it would be absolutely terrifying. It wouldn’t be fun anymore."
This article originally appeared on VICE ID.