Characterizing the Nature and Features of Misophonia: A Mechanistic Approach

Abstract

Misophonia is a newly defined sound intolerance disorder that implicates the defensive motivational systems across cognitive, affective, attentional, physiological, and behavioral domains (Swedo et al., 2022). The nature of misophonic triggers and reactions is highly variable, necessitating the need for idiographic assessment of relevant mechanisms (Brout et al., 2018). Still, despite prevalence estimates ranging from 12 to 20% (Vitoratou et al., 2023; Wu et al., 2014; Zhou et al., 2017), and significant distress and functional impairment associated with this condition, the nascency of misophonia literature limits effective assessment and treatment. Existing measures have largely relied on self-report tools based on unvalidated diagnostic criteria that focus on trigger types and frequency, rather than on a more holistic understanding of emotional functioning, impacts to self-concept, and coping strategies. In addition, few studies have helped to build a mechanistic understanding of processes that can be targeted for change via psychological interventions. One key challenge to advancing our understanding of misophonia has been developing measurement tools that holistically and dimensionally reflect relevant constructs in this disorder. A second key challenge in developing effective interventions to treat misophonia has been limited granular understanding of maintenance factors and mechanisms of change that can be leveraged in treatment. This dissertation consists of three original studies that aim to characterize and understand the nature and features of misophonia, and to strengthen a mechanistic approach to assessment and treatment of this condition. Each study utilizes a different community sample of adults across the United States. Chapter 2 details the creation and preliminary validation of the Duke Misophonia Interview (DMI; Guetta et al., 2022a), the first semi-structured clinical interview to assess misophonia in adults. The DMI can be used by both clinicians and researchers to advance our understanding of this understudied disorder and design corollary interventions. Chapter 3 works to further examine components of emotional functioning in misophonia. Findings from this study (Guetta et al., 2022b) suggest that targeting processes of emotion regulation is crucial in treatment for misophonia. Implications of these results also suggest that how individuals perceive and respond to triggers, shaped by learning histories and chronic stress, may impact misophonia severity. Chapter 4 then explores the relationships among perceptions of stress, trauma history, and traumatic stress in adults with misophonia. Results from Chapter 4 (Guetta et al., 2024) indicate that, although there is overlap in transdiagnostic factors between trauma and misophonia (e.g., perceived stress), there is no evidence for a causal link between traumatic events and the development of misophonia. These findings provide further support for integrating idiographic assessment tools to understand individualized histories of chronic stress, as well as the perceptions of stress during misophonic reactions and in functioning more broadly. Taken together, these three studies add to the nascent literature on mechanistic approaches to assessment and treatment of misophonia in adults. This dissertation concludes with a discussion of the limitations of this research and explore opportunities to apply the DMI and identified treatments targets for future intervention work.