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In extreme cases, sufferers have committed suicide.

Kathryn Renée Thomas was seven when it first happened. She was sitting at the dinner table with her parents and becoming acutely aware of how loudly they chewed.

Kathryn, a writer and actor on TV Land’s “Teachers,” suffers from misophonia, an affective sound processing disorder. Misophonics experience extreme negative emotions, like anger or anxiety, in response to noises generated by other people. These sounds are known as “trigger sounds” and they include everyday noises such as eating, drinking, pen clicking and breathing.

The disorder makes it difficult for misophonics to maintain normal lives. Sounds that other people find unobtrusive can send them into a blind fury. Kathryn says she had to stop taking yoga classes because the sounds of heavy breathing drove her insane. The condition can be so debilitating that sufferers sometimes fall into a heavy depression or resort to suicide to get away from all the noise in their lives.

What is misophonia?

The term misophonia (“hatred of sound”) was coined in 2001, but the condition is not currently classified as a neurological or psychiatric disorder. In fact, misophonia is so under-researched that many clinicians are skeptical — or completely unaware — that the condition exists at all.

Misophonia, also known as selective sound sensitivity syndrome, affects people differently: Kathryn is especially susceptible to mouth noises, like food chewing, gum snapping and liquid slurping. When she hears a trigger sound, her body responds physically: her heart rate increases and she finds herself holding her breath. These physical sensations are accompanied by even stronger emotional ones: Fury, frustration and anxiety are closely followed by guilt and embarrassment. Kathryn says, “I end up feeling guilty for getting mad at my loved ones over nothing. I give myself a really hard time. I don’t want to be angry with the people I love, but it feels uncontrollable.”

The lack of awareness around misophonia means that many people don’t report their symptoms. They worry they might be stigmatized or brushed off. Kathryn says that she’s never asked her doctor about the disorder. “I’ve thought about seeking out help from others, but there’s been so little research and treatment options, I worry that it will be a waste of time and money,” she says. “I don’t want to be let down.”

Researchers are unable to say exactly how many people suffer from misophonia, but a recent study provides new insight into the condition and proves that misophonics aren’t overreacting — they’re just wired differently.

The study’s lead researcher, Sukhbinder Kumar, says he began investigating misophonia after publishing a separate study detailing how people react to sounds while inside MRI machines.

When misophonics saw Kumar’s research, they began reaching out to him to talk about their conditions. As more and more e-mails arrived in his inbox, Kumar developed an experiment to learn more about the disorder.

Kumar and his team of researchers at Newcastle University in England assembled 20 misophonics and 22 control subjects to learn how the condition affects the brain. Subjects were put inside an MRI machine and exposed to three sounds: a trigger sound (like eating or breathing) an annoying sound (like a baby crying or a person screaming) and a neutral sound (like rain falling).

Both groups experienced similar physiological and emotional reactions to annoying and neutral sounds, but misophonics had significantly different experiences listening to trigger sounds. When researchers played the trigger sounds, misophonics’ heart rates increased; they began to sweat. Their anterior insular cortexes — the area of the brain that processes emotions — went into overdrive.

What does this mean?

Results from the experiment indicate that people who suffer from misophonia have abnormalities within their brain’s frontal lobe, causing their emotional control mechanism to react excessively upon hearing trigger noises.

Even though researchers were able to definitively prove that misophonics experience a neurological response to trigger sounds, some experts remain skeptical. Ewan McNay, a neuroscientist at the University of Albany, tells CNN: “It’s quite possible that all individuals have a certain set of sounds they would respond strongly to. It’s just that these individuals have a set of sounds that happen to be common everyday sounds.”

‘I felt like I was drowning’

Misophonics report that the condition is sometimes aggravated by stress, a claim that Kathryn confirms. She tells Dose that while she and her comedy team, the Katydids, were writing the first season of their show, “Teachers,” “I felt like I was drowning. I was in a room with ten people at a table who were talking and working together all day long. What do people do when they are sitting trapped in a stressful situation for hours on end? They eat. They chew gum. They slurp coffee.”

She adds, “I became very frustrated because I couldn’t stay focused on what was being discussed in the room because my anger and frustration were so out of control.”

The future of misophonia

Misophonics usually begin experiencing issues with people-generated noises around age 12, but the condition has affected people as young as 5. Nobody knows how misophonia develops and scientists are unsure if the condition is biological, genetic or acquired later in life.

Kumar and his team of researchers hope that their work will “guide ongoing efforts to classify and treat this pernicious disorder.”

For misophonics, studies like this provide a huge source of validation and hope. Kathryn says that the biggest help for her has been realizing that she is not alone in this. She says:

“It was such a huge relief to be able to put a name on [misophonia] and to know that others had the same reactions to what seemed like such a small thing … Having a name and a community of others that deal with it was great, and Kelly Ripa has it, so it must be real, right?!”