Nobody likes a noisy chewer or mouth-breather, but most people find they are minor annoyances. Then there are those that find certain sounds unbearable.
People with this condition, known as misophonia, have a hatred of sounds such as eating, chewing or repeated pen clicking. Called “trigger sounds” by the misophonia community, the response can be an immediate and intense fight or flight feeling.
New brain imaging research has now shown that people with this condition have an abnormality in the emotional control mechanism which causes their brains to go into overdrive on hearing the trigger sounds.
Misophonia Heightened Physiological Response
Brain imaging with fMRI revealed that individuals with the condition show an abnormality in the in the anterior insular cortex, a brain region for emotional control, which causes their brains to go into overdrive on hearing trigger sounds.
The scientists also found brain activity originated from a different connectivity pattern to the frontal lobe. This is normally responsible for suppressing the abnormal reaction to sounds.
They also found that trigger sounds evoked a heightened physiological response with increased heart rate and sweating in people with misophonia.
Dr Sukhbinder Kumar, from the Institute of Neuroscience at Newcastle University, said:
“For many people with misophonia, this will come as welcome news, as for the first time we have demonstrated a difference in brain structure and function in sufferers. This study demonstrates the critical brain changes as further evidence to convince a sceptical medical community that this is a genuine disorder.”
Ventromedial Prefrontal Cortex Myelination
A physical difference in the frontal lobe between the cerebral hemispheres was observed in people with misophonia – with higher myelination in the grey matter of the ventromedial prefrontal cortex (vmPFC).
The study also used functional MRI to measure the brain activity of people with and without misophonia while they were listening to a range of sounds such as;
- Rain, busy café, a kettle boiling – neutral sounds
- Baby crying, a person screaming – unpleasant sounds
- The sounds of breathing, eating – trigger sounds
This showed abnormal connections between this frontal-lobe area and an area called the anterior insular cortex (AIC). This area is in the grey matter of the brain but buried in a deep fold at the side of the brain and is known to be involved in processing emotions and integrating signals both from the body and outside world.
When presented with trigger sounds activity goes up in both areas in misophonic subjects, whilst in normal subjects the activity goes up in the AIC but down in the frontal area. The team think that this reflects an abnormality of a control mechanism between the frontal lobe and AIC.
Dr Kumar says this research opens up future possibilities for therapy:
“My hope is to identify the brain signature of the trigger sounds – those signatures can be used for treatment such as for neuro-feedback for example, where people can self-regulate their reactions by looking at what kind of brain activity is being produced.”
Hearing People Eat Makes Me Want To Punch Them
The term misophonia was coined by US scientists Margaret and Pawel Jastreboff in 2001. Age of onset typically is the pre-teens.
Trigger sounds are most commonly focused on eating, breathing and hand noises such as typing or pen clicking. Responses can include irritation, upset, disgust and extreme rage.
One example is Olana Tansley-Hancock, 29. She was only 8 years old when family meals became unbearable for her. Olana explains:
“The noise of my family eating forced me to retreat to my own bedroom for meals. I can only describe it as a feeling of wanting to punch people in the face when I heard the noise of them eating – and anyone who knows me will say that doesn’t sound like me.
My family were supportive and it was only at University that I found it becoming more of an issue. I found it spread to my housemates and to other noises and it all came to a head on a train journey when I had changed carriages 7 times as the noise of people eating or rustling papers was unbearable.
When I saw my GP at the time, he laughed at me. Then I tried a counsellor but in my case, that made it worse as it made me even more sensitive to sound.
It was only after I searched on the internet for ‘hearing people eat makes me want to punch them’ that I heard of misophonia – and through the misophonia UK website got involved with the research.
Now, I’m a lot better probably through a combination of better bodily awareness and changes I’ve made to my lifestyle. I mediate and have reduced my caffeine and alcohol intake and I am always prepared – so take earplugs on a journey so I can watch a film and ask for headphones at the cinema so block out the sound of people rustling and eating. These steps have helped me manage and understand my condition better.
“This research is a huge relief as it shows there is a physical basis for misophonia which should help others understand the condition. It also opens up the opportunity for better management.”
Image: Surian Soosay/Flickr