Categorical and dimensional brain network-based models of trauma-related dissociative subtypes

Abstract Background Trauma-related pathological dissociation is a multidimensional and disabling phenomenon that involves disruptions or discontinuities in psychological functioning. Despite its prevalence, personal and societal burden, dissociation remains underappreciated in clinical practice, and it lacks a synthesized neurobiological model that could place it in context with other common psychiatric symptoms. To identify a nuanced neurobiological model of pathological dissociation, we examined the functional connectivity of three core neurocognitive networks as related to the dimensional dissociation subtypes of depersonalization/derealization and partially-dissociated intrusions, and the diagnostic category of a complex dissociation disorder, dissociative identity disorder (DID). Methods Participants were 91 adult women with and without: a history of childhood trauma, current posttraumatic stress disorder (PTSD) and varied levels of pathological dissociation. Participants provided interview and self-report data about pathological dissociation, PTSD symptoms, childhood maltreatment history, and completed a resting-state functional magnetic resonance imaging scan. Results After controlling for age, childhood maltreatment and PTSD symptom severity, we found that pathological dissociation was associated with hyperconnectivity within central executive, default, and salience networks, and decreased connectivity of central executive and salience networks with other areas. Moreover, we isolated unique connectivity markers linked to depersonalization/derealization, to partially-dissociated intrusions, and to DID. Conclusions Our work suggests subtypes of pathological dissociation have robust, discernable, and unique functional connectivity signatures. The neural correlates of dissociation may serve as potential targets for treatment engagement to facilitate recovery from PTSD and pathological dissociation. These results underscore dissociation assessment as crucial in clinical and medical care settings.