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Very Long-Term Users of Marijuana in the United States: A Pilot Study

NCJ Number
Substance Use and Misuse Volume: 32 Issue: 3 Dated: (1997) Pages: 249-264
A J Gruber; H G Pope Jr; P Oliva
Date Published
16 pages
This study examined the residual neuropsychological effects of marijuana in long-term frequent users.
The authors recruited a sample of 37 Americans, aged 30-74, who had smoked marijuana on at least 5,000 separate occasions. These subjects were found to span a wide range of ethnic groups, educational backgrounds, occupations, and annual income; they did not display any obvious features that distinguished them from the population as a whole. They typically began smoking marijuana in the 1960's or early 1970's and then continued to smoke heavily into middle adulthood, because they felt that marijuana relieved unpleasant feeling states such as anxiety or depression. Most subjects believed that marijuana use had either no effect or a positive effect on their social lives. Subjects that claimed positive effects cited decreased anxiety in social situations, a structured environment for interacting with others, or decreased interpersonal boundaries. Four subjects, however, believed that marijuana caused them to focus on their own perceptions, thus increasing their isolation. The majority of subjects reported that their marijuana use had not affected their careers, but most said they did not use marijuana at work because they believed that the acute effects of marijuana would impair their performance. Those who reported that marijuana had a positive effect on their career believed that it made them more creative or more relaxed. Of the five who reported a negative effect on their work, three described a lack of ambition and motivation when smoking regularly. This study is apparently similar in its findings to previous relevant studies in finding that frequent marijuana users do not display any striking features, at least on a screening interview, that would sharply distinguish them from the rest of the population. 5 tables and 40 references


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