Proponents of marijuana use have enjoyed a string of successes lately as both Washington and Colorado voted to legalize recreational use of the drug in the November 2012 election. Eight states and the District of Columbia also permit the use of marijuana for medical reasons. Despite the rising potency of the plant’s active ingredient, due to a professional class of growers, and evidence suggesting that the drug slows reaction time and impairs distance perception behind the wheel, most new marijuana regulations, for medical or recreational use, fail to account for these potential risks.
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What’s the Big Idea?
Whether the kinds of impairment caused by marijuana use that have been documented in laboratory conditions translate into traffic accidents is still under debate. Even less sure than the drug’s immediate effects, however, are its long term consequences for users’ health and intelligence. “In one recent study, clinical psychologist…found that people who began using pot earlier in life and used it most frequently over the years experienced an average decline of eight IQ points by the time they turned 38. By comparison, those who never smoked pot had an average increase of one IQ point by the same age.”