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Surprising Science

Does Marijuana Impair the Mind?

The most recent research indicates that smoking marijuana causes no long term cognitive impairment and can actually improve performance on some mental tests. 
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What’s the Latest Development?


The mind altering properties of marijuana are ephemeral and fleeting, according to an authoritative study recently completed at the Australian National University. Over the course of eight years, researchers performed cognitive tests on ‘total abstainers’, ‘current light users’ and ‘former heavy users’ of cannabis. While the former heavy users performed slightly worse on short term memory tasks, the effects of smoking were entirely reversible. In another study, smoking improved performance on word association tests. 

What’s the Big Idea?

Given the legality of cigarettes and alcohol, it is increasingly difficult to see why marijuana is classified as a Schedule I drug along with L.S.D., M.D.M.A. and heroin. Marijuana is far less addictive than tobacco and its effects on cognitive performance are shorter lived than alcohol’s. The stereotype of pot smokers as immobile pizza fanatics who cannot utter coherent sentences is contradicted by the most recent research. Feelings of relaxation and giddiness help explain why people have been using marijuana to self medicate for thousands of years.

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