Moderate drinking before trauma leads to more flashbacks

March, 2010

A study has found that those given alcohol equivalent to around 2 glasses of wine experienced more flashbacks from a video of serious road traffic accidents than those given twice as much alcohol, and those given none. The findings support the view that flashbacks reflect the reactivation of sensory memory in the absence of contextual memory.

A study in which nearly 50 participants consumed either alcohol (.4 or .8 g/kg, around 2 or 4 glasses of wine) or a placebo drink, performed a memory task, then were shown a video of serious road traffic accidents, has found that those given the smaller amount of alcohol experienced more flashbacks during the next week than those given the larger amount of alcohol, and those given no alcohol. Although that may seem to suggest drinking a large amount of alcohol might result in less involuntary re-experiencing of the event, excessive alcohol produced an overall reduction in memory which may be even more distressing if they then imagine a 'worse case scenario.' The findings support the view that flashbacks reflect the reactivation of image-based egocentric representations (based on sensory features) in the absence of a corresponding allocentric representing (incorporating the spatiotemporal context). Alcohol appears to impair allocentric (contextual) memory first.

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