Nails on a chalkboard. A fly buzzing around the room. A child having a tantrum in the next apartment. The drip-drip-drip of a leaking faucet. Anoverheard cell-phone conversation in a public place. Most people would agree that these things are amazingly annoying , but what is it about them, exactly, that irritates us so much?

According to "Annoying: The Science of What Bugs Us," some sounds, like the screech-squeak of nails on achalkboard or the high-pitched drone of a mosquito near one's ear, are irritating because we react to them in a physical way. "It seems to be something intrinsic about that mix of frequencies," said Flora Lichtman, co-author of "Annoying: The Science of What Bugs Us," in a recent interview with NPR . "The change in volume rapidly—it's called 'rough' in acoustics—most people's ears don't like that stimulus."

We all react to sounds, sensations, and situations differently because of our personal experiences, cultural differences, and emotional associations—it's why madeleine cookies trigger memories for Proust , but just make the rest of us feel a little snacky. But in general, the things that annoy us tend to have three things in common, regardless of our personal histories: Unpredictability, unpleasantness, and uncertainty. A perfect example? The over-heard cellphone call.

It's not just the fact that it's rude, points out Lauren Emberson , a psychology graduate student at Cornell University who has studied the annoying nature of "halfalouges"—when you hear only one side of a conversation. It has to do with the way we process information. "Our brains are always predicting what's going to happen next, based on our current state of knowledge—this is how we learn about the world, but it also reflects how we are in the world," she says. "When something is unexpected, it draws our attention in, our brains tune into it because we're this information-seeking, prediction-loving cognitive system."

"The thing that's frustrating about a cell phone conversation is that it's very hard to predict, which was one of the things that we found makes something annoying, usually," adds Lichtman. It's unpleasant, because you can't concentrate on other things while your brain is trying to predict the missing parts of the overheard conversation, studies show. And the fact that you know it must end, but don't know exactly when, ratchets up the annoying factor.

In fact, not knowing the reason for something—why your computer is running slowly, why your 8 am flight still hasn't boarded at 8:25, why traffic is at a standstill even though it's not rush hour—can make it seem even more annoying that it would be otherwise.

So, what can you to keep your irritation in check? In the book, Lichtman and her co-author, NPR Science Correspondent Joe Palca , suggest "cognitive restructuring," where you remind yourself that you shouldn't be annoyed by whatever is pushing your buttons—a baby cries because it has no other way to communicate, for example; that loud coworker is just being her usual, overly perky self. Another trick: Focus on something else."But that doesn't work very well," admits Palca on NPR's "Morning Edition. "So basically the bottom-line is you're stuck: it's annoying, and that's part of life."