What is misophonia? And why do we hear things differently?

For some, silence is golden. Here’s why…
woman with headphones on

Right now, what do you hear? The radio chatting away? The soft rumble of traffic? Birds flitting between trees?

We live our lives to a low chorus, which we largely filter out. Though for some of us, innocent everyday sounds can cause distress, anger and can even put a strain on relationships.

Years ago, we stayed in a Mount Hotham ski chalet with three others. One had a serious aversion to crunching sounds and another couldn’t cope with slurping sounds.

In this tiny, snowed-in space, no yoghurt, cereal, soup, crackers, styrofoam or apples (mostly the apples) were welcome. To keep the peace we agreed tooth brushing would only happen with the bathroom door firmly shut.

You may have a friend or family member with a similar aversion. The nervous grandmother who can’t stomach the sound of children playing loudly. The quiet brother who escapes parties before it’s even polite. The otherwise amicable boss who bans a kitchen with anything more than a kettle.

Woman covering her eyes and woman covering her mouth.
Asturias, Spain, two best friends telling secrets lying in the grass

It’s estimated 20 to 40 per cent of us have a noise sensitivity and, just like touch, hearing is tied to our emotions. You can think of sound as sensory information that’s paired with emotional information (a memory of joy or fear) and stored together in the auditory cortex.

We also know hearing affects mental health. Those with noise sensitivity are more likely to report symptoms of depression, anxiety, anger and nervousness than noise-resistant individuals. Hearing loss and tinnitus (ringing/hissing/whistling/clicking in the ears) increases your risk of depression and anxiety, and in later life hearing loss hastens cognitive decline.

While sound affects our mental and emotional wellbeing, the reverse is true too. In other words, how we feel can impact how we perceive sound, especially in women.

A large 2013 study of reactions to sound showed women who felt emotionally exhausted before performing high-pressure tasks felt that sounds were louder and more painful afterwards. Surprisingly, the men in the study did not report this effect. On a bad day, our tolerance for sound can be diminished, and even normal conversation can be perceived as painful.

For some, having hearing sensitivities can feel like stepping through an emotional minefield all day.

What is misophonia?

Misophonia, also known as 4S or Selective Sound Sensitivity Syndrome, is characterised by extreme reactions to common sounds.

Sufferers describe overwhelming irritability, anger, outrage and disgust upon hearing certain trigger sounds that are innocuous to others.

The tapping of a keyboard, the shuffling of feet, even the self-grooming of a cat can set some people off.

The most common ‘miso’ triggers revolve around human sounds, particularly eating (think crunching, slurping, lip smacking) and breathing (sniffing, snuffling, nose whistling, etc). It can be especially tricky to manage in confined spaces such as buses and aeroplanes.

To cope, sufferers have come up with their own strategies, including wearing ear plugs around the family home to block accidental triggers and eating separate dinners, or at least playing music during their meals.

They also report humming, internal screaming (“No! No! No!”), excusing oneself to ‘use the bathroom’, turning a fan on and cancelling out the offending crunching/slurping with their own crunching/slurping. Sufferers report that stress management and taking sufficient ‘time out’ also seems to boost tolerance.

While there’s little research on the condition, and it’s not yet recognised by the World Health Organization, we do know that it’s not just a personality quirk. Hearing isn’t a factor either, since trigger sounds can occur at any volume, loud or soft, and sufferers frequently score high on audiology assessments. Nor is it an anger issue, despite sufferers occasionally storming off or verbally lashing out.

Scientists are starting to map misophonic brains and have discovered that trigger sounds send them into overdrive. A 2017 study from Newcastle University in Current Biology found the “first evidence of clear changes in the structure of the brain’s frontal lobe in sufferers of misophonia”.

Woman with headphones on.

Brain imaging revealed that misophonic reactions are accompanied by highly exaggerated responses in regions that are critical in emotional processing, and in regulating emotional responses. The researchers also found that trigger sounds evoked a physiological response with increased heart rate and sweating.

Why crunching for one misophone and slurping for another, though?

“We don’t know why people can be averse to a particular sound,” says Catherine Hart, Principal Audiologist at Hearing Australia. “That person may have had an episode or anxiety incident with that sound at some point in their life. Often, they may have other anxieties too. The thing to remember is it’s not an ear issue. For some reason the brain is reacting and filtering that particular sound and it makes an irrational fight or flight response. Sometimes cognitive behavioural therapy (CBT) can help our brains fix the neurological pathways.”

At the same time, some people turn to these very trigger sounds to help them relax. ASMR, or autonomous sensory meridian response, has exploded on YouTube with videos of people hair brushing, tapping, whispering and yes, crunching apples. Those who experience ASMR report euphoric, calming ‘tingles’ from listening.

One “ASMRtist”, called ASMR Darling, who created one of the most famous soporific videos (“ASMR 20 Triggers To Help You Sleep”) has 2.43m subscribers. As the craze has spread, so have the ASMR sounds: the most popular video of 2018 is called “Crushing Crunchy & Soft Things by Car!” by HelloMaphie and has been watched almost one billion times.

For some unlucky misophones, the situation may be compounded by a biological trait called Sensory Processing Sensitivity. According to psychologist Dr Elaine Aron, 15 to 20 per cent of us are highly sensitive people. As well as loud noises and chaotic environments, we may be overwhelmed by strong smells and others’ stress, and need plenty of quiet time to rebalance.

For those with hyperacusis, or decreased sound tolerance, chatting and even their own voice can become unbearable. In this disorder, normal levels of sound are rendered uncomfortable, distorted or painful. It can happen suddenly or gradually, and the most common cause is damage to the inner ear due to aging or exposure to loud noise. You know you have it if you feel compelled to retreat to somewhere quiet or wear ear plugs even when it’s not especially noisy.

“These strategies can backfire though, because you begin starving the brain for sound,” says Catherine Hart. “It’s like when you go to bed, turn off the lights and then suddenly your ears prick up and you’re awake again. What’s happening is that your brain has effectively turned up the radar to search for those signals.”

The treatment, she says, is having your hearing tolerance mapped by an audiologist, then flooding the brain with low-level pleasant sound through sound enrichment therapy (see “Feel the Vibrations”, above). For misophonia, CBT may be the only hope.

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