What’s the last story that really caught you off guard?

I’m still thinking about “Gone Girl,” a twisting story I finished reading years ago. As readers, surprises really stick with us. Feeling surprised as an adult is so rare that it feels juicy and exciting.

Vera Tobin studies the connection between cognition, language and narrative. Her new book, “Elements of Surprise: Our Mental Limits and the Satisfactions of Plot,” dives deep into why readers love a good surprise — and how writers can use the element of surprise successfully.

I asked Vera more about how she got interested in this topic, and what she wants writers to know.

What led you to write this book?

We tend to hear two sweeping narratives about cognition in the popular press. One is, “Let me tell you how amazing your brain is.” The other is, “You are a deeply flawed mess. Human cognition is tragically defective, with biases and flaws and shortcomings we can’t overcome.”

In my book, I wanted to take a different angle. I’m thinking about how humans cleverly make use of those flaws to create amazing things. Instead of asking why we are so interested in fiction, I’m thinking more about how stories create such deep effects on us.

Why are you interested in surprise?

I’m really interested in surprises that hinge on the idea that you were wrong about what was happening. There’s a crucial piece of information you don’t get until late in the game, and you think, “Oh, it was there all along but I didn’t see it.”

I think that kind of story is so pleasing because it walks you through the experience of discovery. The story produces an experience of coming to a satisfying, fresh realization. That’s an experience people really enjoy. It’s the same experience of insight that’s at the heart of mathematicians’ delight in pursuing their studies, and that everybody really enjoys in puzzling out new things about the world.

How do you study people being surprised?

There are two big bodies of cognitive psychology research that play a role in this book. One of them is about the cognitive bias called “the curse of knowledge.” When you know something, or when you think you know something, it’s very hard to fully suppress that knowledge when you’re thinking about what other people know. Little children are terrible at this. Famously really, really terrible at this. They’re terrible at remembering or knowing that other people don’t know what they know.

But it turns out that adults are not that great at this either. You’re not going to make the kind of mistakes that a 3-year-old makes. But the curse of knowledge is really everywhere, and stories take advantage of the curse of knowledge a lot. You give people little anchoring bits of information and get them to overextend their inferences.

The other branch of research shows us people are really, really, really bad at keeping track of where they encountered information. We know it’s important to remember where we heard something, but we lose track. For example, people misremember things that they were told, or read, as if they had experienced them themselves. You saw something on TV 15 years ago, and you may remember that you saw it personally. People make this mistake all the time.

Debunking things doesn’t work very well, because if you say, “Here’s a fact sheet explaining why these common myths about medicine are false,” and you come back a few months later, the people who got the debunking are actually more likely to think the myths are true than people who didn’t.

That’s crazy.

I know, it’s upsetting. What they remember is, “Oh, that’s familiar. I heard that somewhere before,” and they forget the context in which they heard it. This is very upsetting for those of us who are concerned with getting people to understand true facts about the world. But it’s actually really great news for people who want to tell stories.

Do we need to be careful about how we surprise our audiences?

You have to be really careful. There are a lot of risks tied to surprise. Surprises are very satisfying, but surprises can also raise the specter of authorial misbehavior. If you set them up the wrong way, the reader does feel jerked around.

As writers, our challenge is to write compelling narratives that avoid being misleading or taking these risks with your reader if that’s not what you want to do. I know that when I write academic articles, or when I’m advising students about writing them, there’s this temptation to write them like a story, and withhold important information because you know it’s so engaging.

All your intuitions are telling you, “Aha, I’m going to do it this way. I know just how to do this. I know how to give them just enough information, and withhold just enough information,” but it can backfire. Then you’ve written something that’s engaging, but that’s not playing by the right rules for the effect that you’re trying to produce in that circumstance. It is engaging, but in the wrong places, it’s enraging.

What else can writers learn from your book?

The book is full of strategies for writers — like how to finesse information into a passage in such a way that readers don’t notice it, or only notice part of it.

Or, the flip side: If you want people to really notice something, or align themselves with a character’s perspective, it actually helps to emphasize the difference between the reader and the character. Otherwise, the reader will project their own assumptions. They flesh out the character’s viewpoint a lot with what they already know, and are bad at keeping track of the ways that this sympathetic character doesn’t already know everything that they know.