Brain Reactions to Sounds: Misophonia vs. Hyperacusis

A new brain imaging study has identified distinct neural signatures for misophonia and hyperacusis, even when they co-occur. Published in *Cognitive, Affective, & Behavioral Neuroscience*, the research from the University of Illinois Urbana-Champaign provides some of the clearest evidence to date that these often-confused sound tolerance disorders involve different disruptions in brain network communication.

Mapping Brain Responses in Sound Sensitivity

Led by Namitha Jain and senior author Fatima Husain, the team recruited 91 young adults and categorized them into four groups: those with misophonia, those with hyperacusis, those with both conditions (comorbid), and controls without significant sound sensitivity. The goal was to separate the neural mechanisms of these disorders, which frequently overlap in symptoms and co-occur, complicating diagnosis and treatment.

Inside a functional MRI (fMRI) scanner, participants listened to 90 emotionally valenced sounds from a standardized database, ranging from pleasant (like laughter) and neutral to unpleasant (like screams or vomiting). As they heard each sound, they rated how pleasant or unpleasant it felt. The researchers then analyzed whole-brain activation and the functional connectivity—or communication—between key brain networks.

Visual Brain Areas Are Hyperactive in Misophonia

A primary finding centered on misophonia. The group with misophonia, including those who also had hyperacusis, showed a pattern not typically associated with auditory processing. When listening to unpleasant versus neutral sounds, they had heightened activation in visual association areas of the brain.

More telling was the connectivity analysis. The misophonia groups showed reduced connectivity between the salience network—which flags important stimuli—and the visual network during unpleasant sound processing. “This suggests atypical cross-modal sensory involvement,” the authors note. In simpler terms, a trigger sound like chewing may abnormally recruit brain regions involved in vision, possibly related to mental imagery, context, or a heightened cross-sensory alertness that isn’t seen in typical auditory processing. This finding aligns with previous work, such as that discussed in our article “Misophonia vs Hyperacusis: Brain Responses Explained”, which highlights different neural pathways for these conditions.

Impaired Frontal Control Marks Hyperacusis

In contrast, the neural signature for hyperacusis pointed to a problem with regulation. The hyperacusis group exhibited reduced connectivity between hubs of the salience network and frontal control regions in the prefrontal cortex. This communication pathway is essential for top-down regulation—the brain’s ability to modulate its emotional and physiological response to a stimulus deemed intrusive or loud.

“The hyperacusis group exhibited reduced connectivity between salience hubs and frontal control regions compared to misophonia and controls, indicating impaired top-down regulation,” the paper states. This breakdown could explain why sounds at moderate volumes are perceived as unbearably loud or threatening; the brain’s natural dampening mechanism may be faulty. The role of frontal control networks in sound sensitivity is a growing area of interest, as seen in related research on “Reversing Amygdala Plasticity After Hearing Loss”.

Comorbid Group Shows a Combined Pattern

The individuals diagnosed with both misophonia and hyperacusis displayed neural features associated with each disorder. Their brain scans showed the visual area hyperactivation linked to misophonia alongside the impaired salience-frontal connectivity characteristic of hyperacusis. This additive pattern is significant because it demonstrates that comorbid presentation is not a single, muddled condition but appears to involve the distinct neural mechanisms of both disorders operating simultaneously.

Practical Implications for Diagnosis and Treatment

These findings have direct implications for how we understand and approach these disorders. First, they provide objective neural evidence that misophonia and hyperacusis are etiologically distinct, which can help move diagnosis beyond subjective symptom reports toward more precise definitions.

Second, the results point toward different treatment targets. For hyperacusis, interventions that aim to strengthen top-down regulatory pathways or modulate salience detection—such as certain forms of cognitive therapy or neurofeedback—might be most logical. For misophonia, therapies that address the atypical cross-modal visual-auditory coupling or the specific learned aversions to trigger sounds could be more effective. Understanding these distinct brain responses is a step toward personalized management, a theme also explored in our review of “Hyperacusis: Brain MRI Review on Hearing Health”.

“Future research should combine neural and behavioral data to refine mechanistic models and guide targeted interventions,” conclude Jain and colleagues. The study, available with the identifier DOI: 10.3758/s13415-026-01435-z (PMID: 41981382), offers a clearer roadmap for that future work, separating the neural pathways of two complex disorders that too often leave patients in auditory distress.