Consistency of memory for combat-related traumatic events in veterans of Operation Desert Storm

OBJECTIVE: The nature of traumatic memories is currently the subject of intense scientific investigation. While some researchers have described traumatic memory as fixed and indelible, others have found it to be malleable and subject to substantial alteration. The current study is a prospective investigation of memory for serious combat-related traumatic events in veterans of Operation Desert Storm. METHOD: Fifty- nine National Guard reservists from two separate units completed a 19- item trauma questionnaire about their combat experiences 1 month and 2 years after their return from the Gulf War. Responses were compared for consistency between the two time points and correlated with level of symptoms of posttraumatic stress disorder (PTSD). RESULTS: There were many instances of inconsistent recall for events that were objective and highly traumatic in nature. Eighty-eight percent of subjects changed their responses on at least one of the 19 items, while 61% changed two or more items. There was a significant positive correlation between score on the Mississippi Scale for Combat-Related Posttraumatic Stress Disorder at 2 years and the number of responses on the trauma questionnaire changed from no at 1 month to yes at 2 years. CONCLUSIONS: These findings do not support the position that traumatic memories are fixed or indelible. Further, the data suggest that as PTSD symptoms increase, so does amplification of memory for traumatic events. This study raises questions about the accuracy of recall for traumatic events, as well as about the well-established but retrospectively determined relationship between level of exposure to trauma and degree of PTSD symptoms.