Pubdate: Wed, 16 Apr 2014 Source: Denver Post (CO) Copyright: 2014 The Denver Post Corp Contact: http://www.denverpost.com/ Details: http://www.mapinc.org/media/122 Author: Malcolm Ritter, The Associated Press POT SMOKERS' BRAINS SHOW CHANGES, STUDY FINDS New York (AP) - A small study of casual marijuana smokers has turned up evidence of changes in the brain, a possible sign of trouble ahead, researchers say. The young adults who volunteered for the study were not dependent on pot, nor did they show any marijuana related problems. "What we think we are seeing here is a very early indication of what becomes a problem later on with prolonged use," things like lack of focus and impaired judgment, said Dr. Hans Breiter, a study author. Longer-term studies will be needed to see if such brain changes cause any symptoms over time, said Breiter, of the Northwestern University Feinberg School of Medicine and Massachusetts General Hospital. Previous studies have shown mixed results in looking for brain changes from marijuana use, perhaps because of differences in the techniques used, he and others noted in Wednesday's issue of the Journal of Neurosciences. The study is among the first to focus on possible brain effects in recreational pot smokers, said Dr. Nora Volkow, director of the National Institute on Drug Abuse, which helped pay for the work. The results showed differences in two brain areas associated with emotion and motivation - the amygdala and the nucleus accumbens. It was more pronounced in those who reported smoking more marijuana. "I think the clear message is we see brain alterations before you develop dependence," said brain researcher Krista Lisdahl of the University of Wisconsin-Milwaukee. - --- MAP posted-by: Jay Bergstrom