We all have noises that drive us to distraction. A recent study of unpleasant sounds found that a knife on a bottle is the most bothersome noise known to man. The most annoying sounds fall into particular frequency ranges that may actually cause physical pain and thus we find them intolerable. But what about soft and subtle noises — chewing, humming, even breathing — that drive some people to violence, while others barely notice?

Welcome to the world of misophonia. The recently recognized condition describes people who have strong reactions to the ubiquitous sounds of everyday life. Poorly understood, the condition (the name of which means hatred of sound) usually begins in late childhood and worsens over time. Trigger sounds, everything from mouth and nasal noises to pens clicking to the creak of floors, can create a “reflexive emotional flood of rage and panic with a storm of fight-or-flight reactions becoming paramount. Adrenaline flooding, face flushing, heart-pounding and/or shaking and the need to physically flee or attack are often experienced,” according to misophonia.org, a website dedicated to the condition.

A new study from Newcastle University in the U.K. revealed some of the science behind misophonia. Researchers played neutral noises, like the sound of rain, for 20 volunteers with severe misophonia and 22 people who did not have the condition. Then they played unpleasant sounds, like a baby crying, followed by sounds that were found to trigger misophonia, like chewing and breathing. The misophonic group experienced increased heart rates when they heard the trigger sounds.

"Brain scans revealed that the misophonics had heightened activity in the anterior insular cortex (AIC), an area known to play a central role in the system that determines which things we should pay attention to. When the trigger sounds were played, there was not only more activity in this region but also abnormally high levels of connectivity to other regions," New Scientist reports. In other words: In misophonics, the systems that dictate what we pay attention to and what we respond to emotionally are disrupted.

Signs you may have misphonia

No one knows exactly how many people are afflicted with the condition, but after the New York Times wrote about misophonia, people started speaking up about their experiences, including talk show host Kelly Ripa, who suffers from it. "If my husband eats a peach, I have to leave the room," said Ripa.

The support organization Misophonia UK notes these key facts:

  • The age of onset is often around 10-12.
  • The “trigger” sounds that tend to be most difficult are connected with eating and breathing.
  • The reaction starts with the sound (or some aspect of the sound) and often develops to include actions associated with the sound and even anticipation of those actions.
  • The closer the sufferer is emotionally to the “trigger” person, the more offensive the sound tends to be.
  • The reaction is experienced most commonly as extreme rage.
  • The trigger sound can create an overwhelming fight or flight response in the sufferer, so they experience a desire to do extreme violence to the maker of the sound, or to escape the vicinity of the sound at all costs.

People suffering from the condition are often misdiagnosed with phobic disorders, obsessive-compulsive disorder, or bipolar, manic, and anxiety disorders. Experts say the condition is something people probably are born with and is probably not an auditory disorder but more likely a physiological glitch in parts of the brain activated by sound.

How to cope

As of now there is no known cure or treatment. In an attempt to cope with misophonia, individual strategies include earplugs, eating in isolation, white noise generators, prescribed medications, hypnosis, cognitive behavioral therapy and other therapies. There are a number of online support groups, and even fact sheets and letters to help sufferers explain to friends, family or health care providers and legitimatize the condition.

That it's now recognized as a legitimate condition should help validate those who suffer from it. It is hoped that future research will lead to treatment. Until then, if the sound of chewing gum puts you on the brink of violence, know that you’re not alone.

Editor's note: This story has been updated since it was originally published in October 2012.