FRIDAY, March 5 (HealthDay News) -- Moderate drinking before a traumatic event raises the likelihood that people will suffer flashbacks, but heavy drinking doesn't boost flashbacks, possibly because people forget what happened, new research suggests.
The findings could help scientists understand why some people develop post-traumatic stress disorder and others don't, noted the authors of the new study, published online March 3 in Biological Psychiatry.
"Many people who experience a personally traumatic event, such as rape or a road traffic accident, have consumed alcohol beforehand," the study's leader, James Bisby of University College London, said in a university news release. "For the first time, this research gives us an idea of how being under the influence of alcohol might contribute to our well-being later on."
The researchers recruited almost 50 study participants and gave them an alcoholic drink or a placebo drink, then showed them videos of road accidents. In follow-up interviews, the participants were asked whether they'd experienced flashbacks over the next seven days.
Those who'd had a couple of glasses of wine experienced more flashbacks, whereas those who drank significantly more had fewer flashbacks and less memory of what happened, the study found.
Still, heavy drinking before a traumatic incident can be a problem, Bisby and his colleagues pointed out.
"When people have no memory of the traumatic event, as can happen if they consumed a large amount of alcohol beforehand, they are more likely to imagine a 'worse-case scenario,' " co-author Valerie Curran of University College London said in the news release. "This alone can prove to be extremely distressing and debilitating for the individual involved."
The researchers, she said, were continuing their examination to try to provide a "clearer picture of alcohol's ability to affect memory during trauma."
The U.S. National Institute of Mental Health has more on post-traumatic stress disorder.
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