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BackgroundMisophonia is often referred to as a disorder that is characterized by excessive negative emotional responses, including anger and anxiety, to “trigger sounds” which are typically day-to-day sounds, such as those generated from people eating, chewing, and breathing. Misophonia (literally ‘hatred of sounds’) has commonly been understood within an auditory processing framework where sounds cause distress due to aberrant processing in the auditory and emotional systems of the brain. However, recent evidence from brain imaging showing involvement of the motor system while listening to trigger sounds suggests that it is the perception of action (e.g., mouth movement) of the trigger person, and not the sounds per se, that drives the distress in misophonia. Since observation or listening to sounds of actions of others are known to prompt automatic mimicry/imitations in perceivers, we hypothesized that mimicking the action of the trigger person may be prevalent in misophonia. Apart from a few case studies and anecdotal information, a relation between mimicking and misophonia has not been systematically evaluated. MethodIn this work, we addressed this limitation by collecting data on misophonia symptoms and mimicry behaviour using online questionnaires from 676 participants. ResultsAnalysis of these data shows that (i) the tendency to mimic varies in direct proportion to misophonia severity assessed using a self-reported questionnaire, (ii) compared to other human and environmental sounds, trigger sounds of eating and chewing are more likely to trigger mimicking, and (iii) the act of mimicking provides relief from distress to most people with misophonia. LimitationsThe format of the study as an online survey used questionnaires to assess misophonia status. The questionnaire has been used extensively in misophonia research, however it is not fully validated for use in clinical populations, therefore we cannot be certain on the degree of severity of symptoms reported in this study population.ConclusionThis study shows that mimicry is widely prevalent in misophonia and is elicited by the most common trigger sounds of eating and chewing. These data reinforce the idea of hyper-mirroring in misophonia proposed in our earlier work (Kumar et al., 2021). Thus, providing crucial implications for how we treat and interpret misophonia moving forward.

Misophonia is a common disorder characterized by the experience of strong negative emotions of anger and anxiety in response to certain everyday sounds, such as those generated by other people eating, drinking, and breathing. The commonplace nature of these “trigger” sounds makes misophonia a devastating disorder for sufferers and their families. How such innocuous sounds trigger this response is unknown. Since most trigger sounds are generated by orofacial movements (e.g., chewing) in others, we hypothesized that the mirror neuron system related to orofacial movements could underlie misophonia. We analyzed resting state fMRI (rs-fMRI) connectivity (N = 33, 16 females) and sound-evoked fMRI responses (N = 42, 29 females) in misophonia sufferers and controls. We demonstrate that, compared with controls, the misophonia group show no difference in auditory cortex responses to trigger sounds, but do show: (1) stronger rs-fMRI connectivity between both auditory and visual cortex and the ventral premotor cortex responsible for orofacial movements; (2) stronger functional connectivity between the auditory cortex and orofacial motor area during sound perception in general; and (3) stronger activation of the orofacial motor area, specifically, in response to trigger sounds. Our results support a model of misophonia based on “hyper-mirroring” of the orofacial actions of others with sounds being the “medium” via which action of others is excessively mirrored. Misophonia is therefore not an abreaction to sounds, per se, but a manifestation of activity in parts of the motor system involved in producing those sounds. This new framework to understand misophonia can explain behavioral and emotional responses and has important consequences for devising effective therapies. SIGNIFICANCE STATEMENT Conventionally, misophonia, literally “hatred of sounds” has been considered as a disorder of sound emotion processing, in which “simple” eating and chewing sounds produced by others cause negative emotional responses. Our data provide an alternative but complementary perspective on misophonia that emphasizes the action of the trigger-person rather than the sounds which are a byproduct of that action. Sounds, in this new perspective, are only a “medium” via which action of the triggering-person is mirrored onto the listener. This change in perspective has important consequences for devising therapies and treatment methods for misophonia. It suggests that, instead of focusing on sounds, which many existing therapies do, effective therapies should target the brain representation of movement.