Editor's note: This popular story from the Daily Briefing's archives was republished on May 11, 2020.

Do you hate the sound of someone chewing gum or blowing their nose? For some people, sounds like these are more than just an annoyance—they ignite intense emotional reactions due to a condition called "misophonia."

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Doctors still don't know much about the condition, but recent research is uncovering clues about the condition, April Fulton writes in NPR's "Shots."

What is misophonia?

Misophonia is a condition in which otherwise ordinary sounds cause people to experience intense emotions, such as anger or fear, Fulton writes.

Help patients take an active role in their care

For Ellie Rapp, an 18-year-old who has the condition, the sound of people chewing can trigger an intense visceral response. "My heart starts to pound," she said. "I go one of two ways. I either start to cry or I just get really intensely angry. It's really intense. I mean, it's as if you're going to die."

Rapp said she has experienced symptoms like these for as long as she can remember, but she didn't know the cause until she was in middle school and found an article about misophonia on the internet.

According to Jaelline Jaffe, a psychotherapist who specializes in misophonia, mouth sounds are common triggers for patients with the condition. "Chewing is almost universal. Gum chewing is almost universal," she said. "They also don't like the sound of throat clearing. Coughing, sniffing, nose blowing—a number of things." She added, "It's as if the survival part of the brain thinks somehow it's being attacked or it's in danger."

Very little is known about misophonia, Fulton writes. The condition received its name only in 2001, when a group of scientists who wrote a paper describing the symptoms of the disease.

Experts disagree over whether the condition should be classified on its own or as a subset of a different condition, and it still isn't listed as a diagnosis in the DSM-5. But a recent study published in Current Biology may shed some light on the condition.

Study details

For the study, researchers looked at 20 adults with misophonia and 22 without it and asked them to rate the unpleasantness of a variety of sounds. These included common misophonia triggers, such as eating and breathing, as well as universally disliked sounds such as nails on a chalkboard, and neutral sounds such as footsteps.

Phillip Gander of the University of Iowa, who studies how the brain processes sound and was one of the researchers on the study, said the researchers found that "the response to the neutral sounds and negative sounds were the same in both groups." However, people with misophonia rated the eating and breathing sounds as highly disturbing, while those without misophonia did not.

Gander added that the patients with misophonia showed classic symptoms of stress when hearing these sounds. "Their heart rate increased and it made their palms sweat more," he said. Those patients also showed unusual brain activity while hearing the trigger sounds, Gander said. "In the misophonia group, the activity was far greater in particular parts of their brain," he said, especially in the parts that process emotions.

Still more to learn

Steven Taylor, a professor in the department of psychiatry at the University of British Columbia who was not involved in the study, said the study is interesting limited. First, the study was very small, and the patients' misophonia was diagnosed only via a questionnaire.

"In studies of clinical conditions like misophonia, diagnosis by questionnaire is typically inadequate. A face-to-face interview with a trained clinician (e.g., a psychologist) is typically needed," Taylor said.

The study also didn't identify the cause of misophonia, just that it's associated with some particular brain regions, Taylor added.

Still, Marsha Johnson, an audiologist who was among the first to identify misophonia who was not involved in the study, said the study was "phenomenal," adding that it was "the first piece of research that showed our population that what they had was real."

Johnson is trying to spread awareness of misophonia by speaking at conferences and leading online groups, Fulton writes. However, since the disease isn't listed in the DSM-5, it's difficult for doctors to identify and rare for insurers to cover. Fulton reports. "The problem is, the whole field currently lies undefined," Johnson said.

There aren't any surefire treatments for misophonia, Fulton reports, but there are some options to help people with misophonia cope with the condition.

For Rapp, noise-cancelling headphones have helped, as has a change in her outlook on life. "Misophonia ... I would say it used to define who I am, but now I just see it as another part of my life," she said (Fulton, "Shots," NPR, 3/18).

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