Abstract
Misophonia is a condition where a strong arousal response is triggered when hearing specific human generated sounds, like chewing, and/or repetitive tapping noises, like pen clicking. It is diagnosed with clinical interviews and questionnaires since no psychoacoustic tools exist to assess its presence. The present study was aimed at developing and testing a new assessment tool for misophonia. The method was inspired by an approach we have recently developed for hyperacusis. It consisted of presenting subjects (n = 253) with misophonic, pleasant, and unpleasant sounds in an online experiment. The task was to rate them on a pleasant to unpleasant visual analog scale. Subjects were labeled as misophonics (n = 78) or controls (n = 55) by using self-report questions and a misophonia questionnaire, the MisoQuest. There was a significant difference between controls and misophonics in the median global rating of misophonic sounds. On the other hand, median global rating of unpleasant, and pleasant sounds did not differ significantly. We selected a subset of the misophonic sounds to form the core discriminant sounds of misophonia (CDS Miso). A metric: the CDS score, was used to quantitatively measure misophonia, both with a global score and with subscores. The latter could specifically quantify aversion towards different sound sources/events, i.e., mouth, breathing/ nose, throat, and repetitive sounds. A receiver operating characteristic analysis showed that the method accurately classified subjects with and without misophonia (accuracy = 91%). The present study suggests that the psychoacoustic test we have developed can be used to assess misophonia reliably and quickly. Misophonia, literally hatred of sound 1 , is a condition where subjects experience negative emotional reactions (e.g., irritation, anger and/or disgust) 2,3 and a strong autonomic arousal response when hearing specific "trigger" sounds 4,5. These triggers most often contain human generated mouth sounds (e.g., chewing and slurping), breathing and nose sounds (e.g., heavy breathing and sniffing), throat sounds (e.g., swallowing and throat clearing), but also repetitive sounds of objects operated by humans (e.g., pen clicking and keyboard typing) 2-4. In some cases, visual repetitive stimuli, like leg-rocking or finger tapping, can act as misophonic triggers, a phenomenon known as "misokinesia" 2-4. The physical characteristics of sounds (e.g., intensity and frequency) only partially influence the reaction of misophonics to triggers, rather it is their psychological profile, previous experience, and the context in which triggers are experienced that are the most important 1,4,6,7. For instance, experiencing triggers when one cannot escape from the situation (e.g., plane trip) worsens negative reactions 4. Also, eating and chewing sounds are less annoying when originating from babies or animals, as it is "not their fault" if they are generating them 4. Similarly, an individual's own chewing sounds do not trigger a reaction and are often used as a coping mechanism to "cancel out" incoming triggers 3,4. Other coping mechanisms include listening to music, walking away, avoiding social situations, using earplugs/headphones, and asking the originator of the trigger to stop 2-4. Prevalence reports of misophonia show large variability and range from 6% to 49.1% 8-10. These differ considerably due to the different assessment methods and criterion that were used to define misophonia. Besides, misophonia severity varies: Naylor et al. 10 found that 37%, 12% and 0.3% of medical students had mild, moderate, and severe symptoms, respectively. They suggested that misophonia affects many people mildly, but only a few severely. Misophonia can be accompanied by different comorbidities such as obsessive-compulsive personality traits, depression, and anxiety 2,3,8,11. Perfectionism 2 , neuroticism 2,3,12 , difficulties with emotion regulation 12 , and high interoceptive sensibility 5 are also observed. Generally, no audiological problems are detected (e.g., audiogram, loudness discomfort levels, and speech audiometry) 2,3 , and cases of tinnitus and hyperacusis are scarce (2% and