- Previous studies investigating misophonia have shown connections between the auditory cortex and orofacial motor control areas in the brain in people with sound aversion.
- In a new study, scientists used MRI scans to replicate previous misophonia research on chewing to see what happens in the brain with different sound triggers.
- The results yielded a surprising discovery that could lead to a better understanding of the disorder.
Misophonia, or sound aversion, is a disorder that causes extreme negative reactions to certain noises.
To learn more about what causes the disorder, researchers at The Ohio State University (OSU) studied people with misophonia and people without misophonia to see what happens in the brain when certain sounds are present.
The scientists discovered which parts of the brain involved in misophonia are associated with tapping sounds, and learned that the parts of the brain that contribute to chewing-related misophonia may be different than previously thought.
The results were recently published in the journal Frontiers in Neuroscience.
The Misophonia Institute reports that approximately 20% of the population has misophonia.
According to a
While feeling upset over chewing sounds is one of the most well-known triggers of misophonia, there are other sounds that may trigger anxiety and annoyance. Sniffling, cracking joints, and tapping can also cause an intense reaction.
There is no cure for misophonia, but there are some measures people can take to lessen the effects, such as avoiding situations they know can be triggering.
People can also keep noise-canceling headphones nearby to wear when difficult situations occur. People who have more severe reactions to their misophonia triggers may wish to seek out sound therapy.
Prior misophonia research has mostly focused on how chewing sounds affect people with the condition.
For the new study, OSU researchers recruited 19 participants. Some of the participants had no misophonia symptoms while others experienced the condition.
The participants underwent MRI scanning in three states:
- while in a resting state
- while making speech sounds
- while tapping their fingers
These states allowed the researchers to determine which parts of the participants’ brains were activated at different times.
The researchers scanned the brains of participants who were in a resting state to see if they could replicate the results of a 2021 study. As was the case with the older study, they saw that the people who scored higher for misophonia had a stronger connection in the auditory cortex and orofacial motor cortex regions of the brain.
However, when the participants had to make mouth sounds, this activity did not show the same connectivity, which led the researchers to think the old research “was not capturing true orofacial cortex.”
Additionally, the brain imaging captured when the participants were tapping their fingers showed more activity in the insula area of the brain.
“Using task-based fMRI evidence, we find no selectivity to orofacial action in these previously described ‘orofacial’ regions,” the researchers wrote. “Instead, we observed higher connectivity between finger [functionally defined regions] and insula in mild misophonia, demonstrating neural evidence for non-orofacial triggers.”
The insular cortex is located in the
This study shows misophonia can be caused by more than just chewing noises — it can be triggered by other noises, such as tapping sounds.
The research indicates that not only were previous studies off the mark on the brain region that contributes to misophonia but that the notion it was caused only by sounds related to the face or mouth was off as well.
Dr. Tom MacLaren, a consultant psychiatrist at Re:Cognition Health, not involved in the study, spoke with Medical News Today about the research:
“This is a really interesting study into something that is clearly very prevalent in the general population. “The researchers have made new discoveries about the neural links underpinning the symptom of misophonia and how it can be triggered.”
MacLaren said he believes this discovery has the potential to shape new treatments for the disorder.
“This research could, in the future, lead to new medications or even psychological therapies that might help alleviate the condition faced by so many.”
– Dr. Tom MacLaren, consultant psychiatrist at Re:Cognition Health
Despite the positive implications of the findings, MacLaren noted that the sample size for the study was small and that he hopes to see a study with a larger sample size in the future. “This will help scientists to map out different types of misophonia and its neural basis in even greater detail,” he said.
Heather Hansen, a PhD candidate, graduate teaching and research associate at OSU, and lead author of the study, spoke with MNT about what’s next for misophonia research.
While the new study opened up new avenues for misophonia research, Hansen said there’s still much to be examined. She listed the following questions that she’d like to answer in future research:
- How do these neural differences in misophonia develop?
- Do the differences precede misophonic experiences, such that we could potentially detect the onset of misophonia neurally and intervene before it gets worse?
- Do they come about as a result of a person’s misophonic aversion?
“After seeing the novel results of this study, I’m specifically interested in studying people with more extreme levels of misophonia and with both orofacial and non-orofacial triggers, now that we have neural evidence that misophonia extends past oral [or] nasal aversion,” Hansen said.
“Moving forward, now that we see mounting evidence of non-orofacial triggers in misophonia, we can research more effective strategies to help people cope with all the various ways the condition presents itself.”
– Heather Hansen, lead author of the study
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