Depersonalization-derealization disorder (DDD), a dissociative disorder encompassing disconnections from the self and from reality, remains a widely unknown and underdiagnosed condition. The broad aim of this thesis is to generate a better understanding of DDD from a body-based perspective and to present DDD as a suitable candidate for Dance Movement Therapy (DMT). In the current literature, there is a clear lack of work exploring the potential benefits of body-based therapies for DDD. I first explore DMT and the often-neglected neurocognitive concepts that may be involved including embodied cognition and interoception, with Chapter 2 presenting an in-depth review of controlled trials of DMT for clinical mental health conditions.
Chapters 3 and 4 are focused on better characterizing and understanding DDD. Chapter 3 presents a latent profile analysis of psychometric measures of depersonalizationderealization, anxiety, and dissociation to determine whether symptom heterogeneity in DDD is attributable to the presence of latent subgroups. Chapter 4 presents a study examining the role of verbal suggestibility in DDD and its relationship to depersonalization-derealization symptoms, mindfulness, anxiety, and visual imagery. Both of these chapters have implications for the aetiology, mechanisms, treatment, and classification of DDD.
Chapters 5 and 6 explore DMT for DDD, with Chapter 5 presenting an online intervention study and Chapter 6 presenting an in-person intervention study. Two controlled dance tasks to differentially engage with the body as a means of symptom reduction in DDD were developed: one promoting explicit body awareness and the other implicitly boosting the salience of bodily signals. Dance is presented as a bespoke and efficacious tool to reduce symptoms in DDD whilst improving a sense of body awareness. This research highlights the need for a better understanding of bodily processes in DDD and provides compelling evidence for the continued development of body-based interventions targeting both interoception and mindfulness in this population and in dissociation, more broadly
