Trauma-related altered states of consciousness in post-traumatic stress disorder patients with or without comorbid dissociative disorders.

Background: The four-dimensional ('4-D') model has been proposed as a theoretical framework to understand and delineate trauma-related dissociative experiences, categorizing symptoms into trauma-related altered states of consciousness (TRASC) and normal waking consciousness (NWC), which occur along four dimensions: time, thought, body and emotion. Objective: The main aim of the present study was to evaluate the validity of this model in patients with post-traumatic stress disorder (PTSD), with and without comorbid dissociative disorders. Method: The predictions of the 4-D model were tested in 142 patients with PTSD, with (N = 46) and without (N = 96) comorbid dissociative disorders. Results: As predicted by the 4-D model, experiences of TRASC were less frequent and more specifically related to other measures of dissociation, dissociative disorder comorbidity and a history of childhood sexual abuse compared to experiences of NWC. The predicted lower intercorrelation of TRASC was not supported. Conclusion: The 4-D model represents a promising framework for understanding dissociation across trauma-related disorders.