Posttraumatic stress disorder (PTSD) is characterised by alterations in autobiographical memory for traumatic and non-traumatic events. Studies that focus on event construction - the ability to search for and identify a specific event - have documented overgeneral memory in PTSD. However, the quality of autobiographical memory also depends on the ability to elaborate on an event once constructed by providing additional details. In a prior study, individuals with PTSD generated as many episodic (event-specific) details as trauma-exposed controls when demands on event construction were minimized, albeit the PTSD group generated more non-episodic details. The current study sought to further characterize PTSD-related alterations in event elaboration by asking participants to describe a stressful negative event specified by the experimenter, thus minimizing event construction demands. Narratives were scored for episodic and non-episodic details and relations with measures of executive function and self-reported avoidance were examined. Compared to controls, the PTSD group generated narratives with equivalent episodic detail but greater non-episodic detail, including semantic information and repeated or extended events. Non-episodic detail generation was associated with greater avoidance but not executive functions. Elaborated non-trauma memories may be perceived as overgeneral in PTSD due to greater generation of non-episodic details, rather than diminished episodic detail.
Keywords: PTSD; autobiographical memory; avoidance; executive functions.