Misophonia vs Hyperacusis: Brain Responses Explained

A new fMRI study of 91 young adults has identified distinct and overlapping brain activation patterns in misophonia and hyperacusis. The research, led by Dr. Namitha Jain and Dr. Fatima Husain at the University of Illinois Urbana-Champaign, provides some of the clearest neural evidence to date that these often-confused sound tolerance disorders involve different underlying mechanisms, even when they co-occur.

Mapping Brain Activity to Specific Sounds

To separate the neural signatures of misophonia and hyperacusis, the team recruited participants across four groups: those with misophonia only, hyperacusis only, both conditions, and controls with no sound sensitivity issues. During a functional MRI scan, each person listened to 90 emotionally charged sounds from a standardized database, ranging from pleasant and neutral to unpleasant. They rated how pleasant or unpleasant each sound was while their brain activity was measured.

This task-based approach allowed researchers to see not just which brain regions activated, but also how different neural networks communicated—or failed to communicate—when processing sounds with negative emotional content. The analysis focused on whole-brain activation and functional connectivity between key network hubs.

Misophonia Shows Cross-Sensory Brain Involvement

A central finding was that individuals with misophonia, regardless of whether they also had hyperacusis, showed a unique pattern. When listening to unpleasant versus neutral sounds, their brains displayed hyperactivation in visual association areas. Simultaneously, there was reduced functional connectivity between the salience network—which flags important stimuli—and these visual regions.

This suggests the misophonic brain may be processing specific, trigger sounds in an atypical, cross-modal way. “This points to a cross-sensory involvement,” the authors note, where a sound like chewing might involuntarily engage brain areas typically used for visual processing or mental imagery. This neural pattern could help explain the highly specific and often visually-linked nature of common misophonia triggers. For more on how the brain responds to trigger sounds, see our related article on brain responses in misophonia versus hyperacusis.

Hyperacusis Points to a Breakdown in Regulation

In contrast, the hyperacusis group exhibited a different neural signature. Their primary difference was reduced connectivity between hubs of the salience network and frontal control regions in the prefrontal cortex. This connection is vital for top-down regulation—the brain’s ability to modulate its emotional and physiological response to a stimulus deemed salient or annoying.

The impairment in this pathway indicates that in hyperacusis, the brain may successfully flag a sound as uncomfortably loud or intense, but then lacks the regulatory circuitry to dampen the resulting distress. This mechanism appears distinct from misophonia, where this particular salience-to-frontal connectivity was preserved for generally unpleasant sounds.

When Disorders Co-occur

The comorbid group, with both misophonia and hyperacusis, displayed neural patterns associated with each condition. This additive effect in the brain supports the clinical observation that these are separate but frequently overlapping disorders, rather than different expressions of a single condition. The study confirms that comorbidity is a real, measurable state in the brain, not just a diagnostic overlap.

Implications for Diagnosis and Future Treatment

These findings have direct practical implications. Clinically, they provide biological evidence that can help differentiate between misophonia and hyperacusis, leading to more accurate diagnoses. A person reacting violently to chewing sounds but not to moderate-volume traffic noise may have a different underlying neural profile than someone who finds all environmental sounds painfully intense.

The distinct mechanisms also suggest different treatment targets. For hyperacusis, therapies aimed at strengthening top-down cognitive control or modulating salience network activity—such as certain forms of cognitive behavioral therapy or neurofeedback—might be particularly relevant. For misophonia, approaches that address the cross-sensory aspect, like counter-conditioning that alters the visual association, could be explored. Understanding these neural pathways is a step toward more personalized interventions, similar to how research is using neural data to guide wearable tech for hearing health.

The study, published in Cognitive, Affective, & Behavioral Neuroscience, calls for future research to combine this type of neural data with detailed behavioral measures. This will help build more complete models of what causes these debilitating reactions to sound and how to best treat them. For a look at how brain stimulation is being studied for related auditory disorders, you can read about research into deep brain stimulation for tinnitus.

Source: Jain N, Ajmera S, Shahsavarani S, et al. Differential brain responses to affective sounds in misophonia and hyperacusis: A task-based fMRI approach. Cogn Affect Behav Neurosci (2026). doi:10.3758/s13415-026-01435-z. PMID: 41981382.