Why teen brains are wired to love 'Charlie Charlie' and the supernatural

It’s almost summer, meaning it’s summer camp season, meaning it’s the time of year when the best urban legends, ghost stories, and miscellaneous paranormal activities come back to life. This year, “Charlie Charlie” is the hot new unearthly trend.

Over the past two days, the #CharlieCharlieChallenge has gone viral on Twitter, Tumblr, Vine, and whatever other platforms teens have access to. A cross between a ouija board and saying “Bloody Mary” (or “Biggie Smalls”) in front of a mirror with the lights turned off, “Charlie” appears to be 2015’s clear successor to “Slender Man” (though let’s hope a less grim option).

We all know that preteens and teens will go completely apeshit over just about anything—but supernatural horrors resonate uniquely. Why? It turns out the mushroom cloud that is the teen brain is perfectly primed for this type of thrill.

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Fusion spoke with Stephen Schlozman, an assistant professor of psychiatry at Harvard Medical School and author of the novel The Zombie Autopsies: Secret Notebooks from the Apocalypse, about why the teenage brain so readily embraces spooky stuff, and he walked us through the science.

“You hit this adolescent stage, and it’s exciting because suddenly the world is full of conflicting ideas, whereas before it was pretty straightforward,” Schlozman told Fusion. As the world around you changes and previously held truths begin to crumble, why wouldn’t it be possible for the supernatural to be real, too?

What is a Charlie?

First a quick primer on the viral trend. In order to “summon” Charlie, the summoner stacks two pencils perpendicularly on a sheet of paper and labels two quadrants diagonally across from each other “Yes,” and the other two quadrants “No.” Then the fun begins. The summoner asks, “Charlie, Charlie, are you here?” and supposedly, the pencil on top moves like a dial (guided by Charlie, obviously) toward either “Yes” or “No.”

The “Charlie Charlie challenge” is supposedly a Mexican tradition, though the BBC pretty much debunked those origins on Tuesday. Like many other ghost stories, no one is really sure who Charlie is or how he died (or why we’re not calling him Carlos or Carlito?), but the theories range from a boy who committed suicide to an actual real-life demon to a child who died of abuse (h/t Yahoo answers, 2010).

It’s also unknown if Charlie is supposed to be benign or evil (ghosts are so fickle these days), but the hullaballoo has been enough to prompt a Catholic priest in Philadelphia to pen an open letter warning about the dangers of inviting a demon into your home.

Thinking about thinking

According to Schlozman, the key to teens’ attraction to “Charlie Charlie” and other supernatural stuff boils down to the fact that, for the first time, their brain allows them to think about the way they think—which is fun to explore.

“As your brain gets bigger, you’re able to hold onto multiple ideas at the same time,” Schlozman told Fusion, “which is actually one of the definitions of the adolescent brain, this idea of recursive thinking, and your ability to say, ‘I know that he knows that she knows.'”

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Pre-adolescent children are, by nature, egocentric, unable to see the world from another’s perspective and assuming everyone sees the world from theirs. But as the adolescent brain develops, kids begin to understand that this is not the case. And this shift in perspective lends itself to horror tropes. “Maybe ghosts are real,” the adolescent brain thinks, “maybe that voice I heard in the middle of the night wasn’t just the house settling,” explained Schlozman.

The doctor added that while young children are highly aware of rules, as they get older, they’re naturally propelled to experiment with breaking these rules. Still, even notoriously rebellious teens tend to avoid completely dangerous decisions. (We are, as he said, self-preserving beings.) Playing around with the “supernatural” offers teens a way to put themselves in the mentality of danger without actually bringing harm to themselves.

“I think kids are interested in the dares that aren’t actually all that dangerous, but have that feeling of danger to them,” said Schlozman. But what’s actually going on inside their brains?

Brain games

Throughout adolescence, the brain prunes away excess synapses and connections in order to streamline its efficiency. On top of that, the brain undergoes a process known as myelination, or the production of the “myelin sheaths” that help insulate our neurons and increase the speed of connections.

Myelination starts with the more primitive parts of the brain, then moves onto more sophisticated and higher-level functioning later. Specifically, the limbic system (which governs emotional responses) is developed before the prefrontal cortex (which governs behavioral functions like impulse control, judgment, and empathy). In other words, teen brains’ reasoning abilities can’t always keep up with their emotional responses.

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High emotions, a need to explore the rules of the world, and undeveloped higher cognitive skills? It’s almost as if “Bloody Mary” and “Charlie Charlie” and every other “supernatural” #trend were simply made for the teenage brain.

Indeed, “Charlie Charlie” reminds teens that their limbic systems are limber. It’s a way for them to feel like they’re breaking some kind of rule, toying around with expectations and some pretty spooky shit. And it’s perfectly low stakes—the only thing that’s risked when getting in touch with little Charlie is a sheet of paper. AND YOUR SOUL.