Stacks of library books. (iStock)

I have been a nerd my whole life. I was always "that kid," the one who read in a corner at recess and talked about Jo March and Ponyboy as though they were real people. I have a vivid memory of myself at 8 or 9, staying up far past my bedtime to read Katherine Paterson's "Bridge to Terabithia" by flashlight. When I reached the gut-wrenching ending, I began sobbing loudly enough to summon my mother from down the hallway.

As soon as she saw the book in my hand, she knew nothing was actually wrong. "I think I comforted you," my mom told me recently. "I hope I didn't say, 'Stop crying, it's not real.' " (She claims not to remember any details of this incident.)

When I told this story to Keith Oatley, a perfect stranger, he told me I didn't need to feel silly for getting so worked up over the fates of fictional characters.

"You were just being a human being," he said.

Oatley would know — he is a cognitive psychologist at the University of Toronto, a novelist and the author of a new review in the journal Trends in Cognitive Sciences looking at the psychological effects of fiction. In his review of the past decade of research on the subject, he concludes that engaging with stories about other people can improve empathy and theory of mind.

"When we read about other people, we can imagine ourselves into their position and we can imagine it's like being that person," Oatley said. "That enables us to better understand people, better cooperate with them."

In 2006, Oatley helped conduct a study that linked reading fiction to better performance on empathy and social acumen tests. Participants were first tested on their ability to recognize author names — a decent proxy for figuring out how many books they read and what kinds.

"We are all familiar with the stereotype of the bookworm," he and his co-authors wrote. "An image leaps automatically to mind: that of a nebbish and unfashionable individual, wearing spectacles, whose demeanor is largely characterized by the social awkwardness one might expect from someone who has chosen the company of print over peers." (Note: As a bespectacled book reader, I find that this this description hits uncomfortably close to home.)

But the second half of the study suggested that stereotype is unfair, Oatley said. The participants were then scored on Interpersonal Reactivity Index, which is designed to measure empathy, and the Reading the Mind in the Eyes Test, which gauges ability to interpret the mental states of others by asking people to associate pictures of actors' eyes with an emotion.

Participants who knew the most fiction writers on the author recognition test scored far higher on the measurements of social acumen.

"People who read more fiction were better at empathy and understanding others," Oatley said.

Any author would tell you as much (then again, they have a vested interest in doing so). But according to Oatley, psychology had long been "very sniffy" about studying fiction.

"People thought it was just made up," he said. "So who knows what could be happening?"

But the past decade and a half has seen a shift in that trend. In 2000, Jemeljan Hakemulder at Utrecht University in Germany published "The Moral Laboratory," a book outlining the results of almost two dozen experiments that linked reading to better social skills. A 2013 study in the American Psychological Association's journal Psychology of Aesthetics, Creativity, and the Arts found that the process of imagining scenes while reading led to an increase in empathy and prosocial behavior. Raymond Mar, a psychologist who co-authored the 2006 study with Oatley, has found that the parts of the brain used for inferring thoughts and feelings of others — a phenomenon called "mentalizing" — light up in an MRI machine when people are processing stories.

This phenomenon is probably form neutral — studies of people viewing dramatic television shows such as "The West Wing" and the "The Wire," or playing immersive, narrative video games, found that they had the same effect as reading literature.

But the type of story matters, according to some research. In 2013, researchers at the New School made a splash when they published an article in Science arguing that literary fiction — as opposed to non fiction or a popular genre, like sci-fi — temporarily enhanced a skill known as theory of mind, the ability to imagine what might be going on in someone else's head. The authors said that literary fiction tends to focus more on characters' interior lives than nonfiction or genre stories; readers have to get inside the heads of the characters, which is what leads to the psychological effect. A 2014 study found something similar: participants who read an excerpt from a novel about a Muslim American woman were less likely to make broad assumptions based on race than those who just read a synopsis of the story, suggesting that the way a story is told is as important as what is being said.

Oatley compared reading to being in a flight simulator: "You experience a lot of situations in a short span of time," he said, far more so than if we went about our lives waiting for those experiences to come to us.

Books, he continued, are life simulators. They allow us to see ourselves in someone else.

"Really, all art is metaphor," Oatley said. "When we read, we become Anna Karenina or Harry Potter. ... We understand them from the inside."

He believes that this is helping to make us better at being human. Oatley noted that the earliest cave art emerged around the same time as the first burials. Both are forms of storytelling, a way of linking a physical truth — marks on a wall, a dead body in a shroud — with an imagined one — "these marks are a horse," he said "this person is alive in our memory or another world." And both phenomena, for the most part, are unique to humans, one of the world's most cooperative species.

"Because we're extremely social we have to understand other people, and the whole of culture is based on this," he said. Funerals, art, literature, prestige TV — all of these things are evolutionary adaptations that give us insight into one another's minds.

"Without doing that you can't cooperate," Oatley said. "And this is pretty much the center of what it means to be human."

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