Laura A. Halvorsen is a 2014 graduate of the PsyD Program in Clinical Psychology at Antioch University, New England.


peritraumatic dissociation, dissociation, PTSD, trauma

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Current literature on the relationship between posttraumatic symptoms and dissociation that occurs during the time of a trauma, or peritraumatic dissociation, appears to be contradictory and inconclusive. Conflicting findings in the empirical literature that disagree on the nature of this association (whether peritraumatic dissociation is a risk factor for PTSD or a neutral or even protective evolutionarily-derived phenomenon) may originate from the lack of conceptual clarity regarding the construct of dissociation, and lack of differentiation between peritraumatic dissociation and dissociation that persists after a traumatic event. This dissertation details a theory for differentiating clusters of peritraumatic dissociation based on distinct phenomenology, neurological profiles, and evolutionary or adaptive purposes. These clusters are hypothesized to carry different degrees of risk for developing persistent dissociation and posttraumatic symptoms. These theoretical clusters will be applied to existing autobiographical accounts of traumatic experiences to illustrate their phenomenological differences. A comprehensive study design entailing factor and cluster analysis to empirically investigate the notion of discrete clusters of peritraumatic and persisting dissociation patterns of trauma response, and to determine the associations between each natural "grouping" of peritraumatic dissociation and posttraumatic symptom severity is proposed. Finally, implications of the theory and proposed study, as well as possible limitations of the theory, are discussed.