All About the Invidious Irritants That Irk Individuals

You get every bit as annoyed as I do by car alarms that never stop, fingernails screeching down blackboards, and a fly buzzing around your head. The prolonged whining of a child, your own or somebody else’s, drives you crazy.

In other words, some annoyances are particular to the individual, some are universal to the species, and some, like the fly, appear to torture all mammals. If ever there was a subject for scientists to pursue for clues to why we are who we are, this is the one.

And yet, as Joe Palca and Flora Lichtman make clear in their immensely entertaining survey, there are still more questions than answers in both the study of what annoys people and the closely related discipline of what makes people annoying.

Mr. Palca and Ms. Lichtman — he is a science correspondent for National Public Radio and she an editor for the network’s “Science Friday” program — skitter all over the map in pursuit of their subject, and at first their progress seems peculiarly random, like one of those robotic vacuums. But in the end they do indeed cover every part of the terrain: from physics and psychology to aesthetics, genetics and even treatment for the miserably, terminally annoyed.

Formulating a good working definition of annoyance is a persistent challenge for researchers. One calls it the weakest form of anger, simply diluted rage. Others cite overtones of disgust (a persistently belching dinner guest), dislike (a concert of atonal music) and even panic (that visceral “get me out of here” reaction to the fingernail on the board).

Still, a few constants emerge. An annoyance is unpleasant. It follows a pattern, but unpredictably so. It will definitely end at some point, but you don’t know when. Finally, it is neither harmful nor dangerous in itself, but it often channels something that is.

In sum, it barges into your brain and takes over. If it is a sound, it occupies enough of your attention to interfere with other thoughts. If it is a situation, it keeps you from where you want to be (the recipe calls for two eggs and you have only one). And if it is a person who is late (again!), it manages to do both.

Because so many annoyances are auditory, sounds are particularly well studied. Sometimes the context creates the problem, like the “halfalogue” of an overheard cellphone conversation: Our brains can tune out a whole conversation but seem programmed to pay attention to half. Sometimes the annoyance is the sound itself. One research group found that midrange frequencies, somewhere between a boom and a shriek, annoyed people more than either extreme. Reaction to sound may be cultural, but then again it may not be: Even members of an isolated African tribe appeared bothered by dissonant music.

Sometimes sound is meant by nature to annoy, like a baby’s wail. One researcher suggested that the fingernail on the blackboard bothers us because our primitive midbrain hears in it a primate’s warning cry.

And sometimes the problem lies more in the ear than the sound. People with perfect pitch report they are routinely driven insane by nebulous halftones that don’t fit into their ordered brains.

Mr. Palca and Ms. Lichtman have a lot of fun with the other large repository of annoyances: our fellow humans. Is there a prototype for the innately annoying person, that car alarm on two legs? Needless to say, there are many.

There are the people who display “uncouth habits, inconsiderate acts and intrusive behaviors” — we are annoyed by those who violate our social norms. Then there are the infinite variations on the unfortunate personality. First on a list of traits that tend to annoy others, interestingly, is that of being constantly annoyed. Then come arrogant and picky.

What about your own personal irritant, the spouse who was so enchanting during courtship and is exactly the opposite now? Studies show that precisely those traits that once attracted often begin to repel. Once he was cool; now he is cold. Once she was adoring; now she smothers. Here the problem seems to be a matter of dose.

People who are annoyed to the point of irritable and beyond might head for a medical evaluation; some neurologic diseases start like this well before other symptoms surface. For these patients antidepressants often work miracles.

For other sufferers, alas, there are few quick fixes. And so when you begin to kick my chair, I could try to pretend that I am Japanese, for it seems that the Asian ideal of subjugation of the self to the group makes for less annoyance with one’s neighbor. I could try to change my expectation that when peacefully seated I will not be jiggled like a fishing line, for it seems that among laboratory monkeys thwarted expectations are a prime source of annoyance. Or I can just turn around and glare at you and tell you to cut it out. Then I will be happy. And you will be annoyed.