Pubdate: Thu, 07 Mar 2002 Source: Advertiser, The (Australia) Copyright: 2002 News Limited Contact: http://www.advertiser.com.au/ Details: http://www.mapinc.org/media/1 CANNABIS 'DAMAGE' A STUDY by a Sydney researcher has found that long-term cannabis users could be damaging their memory and hindering their ability to concentrate. The impairment did not amount to serious brain damage but could be enough to interfere with simple tasks like reading, studying or shopping, Nadia Solowij of the University of NSW said. Dr Solowij led a study by the US Marijuana Treatment Project Research Group which focused on patients seeking help for marijuana dependence in US clinics between 1997 and 2000 The study concluded that chronic heavy pot smokers displayed signs of cognitive impairments serious enough to affect their work, life and ability to learn. "This study has found that there are long-term effects of cannabis use on memory and on attention, and that memory function gets worse with the number of years that cannabis is used," she said. The study examined 51 people who had been using marijuana daily for an average 24 years and compared them to 51 shorter-term users and 33 non-users. As part of the study, the subjects were presented with a list of 15 words and asked to recall them later. "In general we found that the long-term heavy users were recalling approximately three words less than the non-users or shorter-term users," Dr Solowij said. "We found that impairment in memory was there in the group that on average had used for 24 years, but we didn't find any significant difference in the group who had used for about ten years." Dr Solowij said she hoped to determine whether the damage was reversible when she finalised follow-up studies of the subjects later this year. Her findings sparked controversy overseas after her work was published in the March 6 issue of the prestigious Journal of the American Medical Association. Harrison Pope of Harvard Medical School disputed the findings in an editorial and subsequent statements. Dr Pope said Dr Solowij's study had failed to take into account whether the subjects had been taking other drugs or suffered problems like anxiety or depression that could also affect cognitive ability. "The safest thing to say at this point is that the jury is still out on the question of whether long-term marijuana use causes lasting impairment in brain function," he said. While Dr Solowij concedes the jury may be out until her follow-up tests are concluded, her findings add weight to the adage: they don't call it dope 'cause it makes you smart". - --- MAP posted-by: Jay Bergstrom