Fifty Shades of Grey may be a fun read, but it’s not going to help you probe the minds of others the way War and Peace might. That’s the conclusion of a new study, which finds that, compared with mainstream fiction, high-brow literary works do more to improve our ability to understand the thoughts, emotions, and motivations of those around us.

Perhaps it’s no surprise that the lead author of the new study, David Kidd, came to social psychology by way of Russian literature. Now a Ph.D. student at the New School in New York City, he is versed in arguments from literary theorists that divide fiction into two categories. When we read a thrilling-but-predictable bestseller, “the text sort of grabs us and takes us on a roller-coaster ride,” he says, “and we all sort of experience the same thing.” Literature, on the other hand, gives the reader a lot more responsibility. Its imaginary worlds are full of characters with confusing or unexplained motivations. There are no reliable instructions about whom to trust or how to feel.

Kidd and his adviser, social psychologist Emanuele Castano, suspected that the skills we use to navigate these ambiguous fictional worlds serve us well in real life. In particular, the duo surmised that they enhance our so-called theory of mind. That’s the ability to intuit someone else’s mental state—to know, for example, that when someone raises their hand toward us, they’re trying to give us a high-five rather than slap us. It’s closely related to empathy, the ability to recognize and share the feelings of others. Increasing evidence supports the relationship between reading fiction and theory of mind. But much of this evidence is based on correlations: Self-reported avid readers or those familiar with fiction also tend to perform better on certain tests of empathy, for example.

To measure the immediate cognitive effects of two types of fiction, Castano and Kidd designed five related experiments. In each, they asked subjects to read 10 to 15 pages of either literary or popular writing. Literary excerpts included short stories by Anton Chekhov and Don DeLillo, as well as recent winners of the PEN/O. Henry Prize and the National Book Award. For more “mainstream” selections, they looked to Amazon.com top-sellers such as Danielle Steel’s The Sins of the Mother and Gillian Flynn’s Gone Girl, and to anthologies of genre fiction, including a sci-fi story by Robert Heinlein.

When participants finished their excerpts, they took tests designed to measure theory of mind. In one test, the Diagnostic Analysis of Nonverbal Accuracy 2—Adult Faces (DANVA2-AF) test, they looked at a face for 2 seconds and decided whether the person appeared happy, angry, afraid, or sad. In the more nuanced Reading the Mind in the Eyes Test (RMET), they saw only a small slice of a face and picked from four complex emotions such as “contemplative” and “skeptical.”

On average, both groups did slightly better on these tests than control subjects who read either a nonfiction article or nothing at all. This fits with previous research showing a positive relationship between fiction and theory of mind. But among the fiction readers, those who read “literary” works scored significantly higher on the theory of mind tests than those who read popular selections, Kidd and Castano report online today in Science. The absolute differences in scores were hardly dramatic: On average, the literary group outperformed the popular group by about two questions (out of 36) on the RMET test, and missed one fewer question (out of 18) on the DANVA2-AF. But psychologist Raymond Mar of York University in Toronto, Canada, notes that even very small effects could be meaningful, provided they translate into real-world consequences—reducing the likelihood that social misunderstandings could create grudges or leave someone in tears.

Keith Oatley, a cognitive psychologist at the University of Toronto, agrees that any evidence of literature’s effect based on this experimental approach is “big news.” “I’m quite impressed that they managed to find results with these tests.”

Still, the “literariness” argument needs hammering out. Castano believes these results show that fiction’s power doesn’t hinge on exposing readers to foreign viewpoints or offering a persuasive, empathetic message. “For us, it’s not about the content,” he says. “It was about the process.” But Mar points out that there are probably many ways to improve theory of mind, and “different things might work for different people.” Some may find that stories with a moral of acceptance and empathy increase their theory of mind skills, for example, while others might benefit more from the practice of filling in the emotional gaps in an ambiguous story.

Cognitive neuroscientist Vittorio Gallese of the University of Parma in Italy, who is also exploring how the brain responds to works of art, finds the new link between real and fictional worlds exciting, but is skeptical of the distinction between literary and mainstream fiction. “This is a very slippery ground,” he says, because historical tastes often move the boundary between “high” and “low” art. For example, he says, Honoré de Balzac’s The Human Comedy was released in serial form as a work of “popular” fiction, but has since attained the status of a classic.