Misophonia, Hyperacusis, and Brain Chemistry: What This Study Did and Did Not Find

People with misophonia or hyperacusis are often told that their brains may be “overexcitable” or chemically unbalanced. A new brain imaging study helps clarify this idea by asking a very specific question:

Are these sound intolerance conditions caused by abnormal levels of key brain chemicals?

In late 2025, a research team led by Jamie Ward investigated the brain chemistry of people with misophonia and hyperacusis using advanced magnetic resonance spectroscopy.

Looking directly at brain chemistry

The study focused on two important brain chemicals:

• Glutamate, which is involved in excitation and neural signalling
• GABA, which plays a key role in inhibition and calming neural activity

These chemicals were measured in:

• The auditory cortex, which processes sound
• The insular cortex, which is involved in emotion and bodily awareness
• A control region of the brain unrelated to sound

Importantly, the study carefully excluded people with other conditions such as tinnitus, migraine, or autism, so the findings could be interpreted more clearly.

What the researchers expected to find

Based on existing theories, the researchers expected that people with decreased sound tolerance might show:

• Higher levels of excitatory chemicals
• Lower levels of inhibitory chemicals

This would support the idea that misophonia or hyperacusis is caused by a chemical imbalance leading to excessive brain reactivity.

What the study actually found

The results were surprising and important.

The researchers found no significant differences in glutamate or GABA levels between people with misophonia, people with hyperacusis, and those without sound sensitivity. This was true across all brain regions examined.

Advanced statistical analyses suggested that these were not weak or inconclusive findings, but robust evidence that large chemical differences were unlikely.

Why this matters

These findings challenge a simple explanation of sound intolerance as a problem caused by abnormal levels of brain chemicals. Instead, they suggest that misophonia and hyperacusis are not driven by static neurochemical imbalances in the auditory or emotional brain regions studied.

This does not mean the brain is not involved. Rather, it suggests that:

• The issue is more likely related to how brain networks function and communicate
• Timing, connectivity, learning, and regulation matter more than chemical concentration
• Sound intolerance reflects dynamic processing, not a fixed chemical defect

What this means for treatment

This study helps explain why treatments aimed purely at altering brain chemistry, such as medication, have shown limited and inconsistent benefit for misophonia and hyperacusis.

It also supports approaches that focus on:

• Brain processing and regulation
• Emotional and threat responses
• Learning and adaptation
• Psychological and behavioural strategies

These approaches work with how the brain responds to sound, rather than trying to correct a chemical imbalance that may not exist.

What this means for patients

For people living with misophonia or hyperacusis, this research offers reassurance:

• Strong reactions to sound are real and brain-based
• They are not caused by a simple chemical fault
• Lack of response to medication does not mean the condition is untreatable
• Change is possible through approaches that target brain function and learning

At Hashir Tinnitus Clinic, care for misophonia and hyperacusis is guided by this broader understanding of brain processing, focusing on personalised assessment and evidence-based support rather than one-size-fits-all explanations.

Learn more

If you would like to read the original open-access research paper, it is available here:

Ward, J., Agbude, R., Smees, R., Simner, J., & Ronen, I. (2025). The neurochemistry of decreased sound tolerance: A magnetic resonance spectroscopy study of misophonia and hyperacusis. Hearing Research.
https://doi.org/10.1016/j.heares.2025.109440

If you would like to discuss how this research relates to your own experience of sound sensitivity, we are always happy to explore this with you during an appointment.