If you were the kind of teen stoner who watched those PSA’s and thought, “I don’t get it, I just see a fried egg,” you might be a little concerned about whether or not the apple fell far from the tree — and whether or not your own kid will figure out how to carve that apple into a sweet fruit pipe some day. In that case, you’ll be pleased to learn that a new study takes a lot of accepted ideas about weed’s negative impact on the brain, rolls it into a fat jay, and burns it.
Published recently in the Proceedings Of The National Academy Of The Sciences, the study compared sets of twins, which makes it easier to to take into account any outside factors that might be underlying reported cognitive decline in marijuana users. Researchers gave 3,066 sets of twins standard IQ tests at ages 9-12, and again at 17-20. In hundreds of pairs, one twin reported smoking while the other was a little angel (or a liar). What they found when comparing users to non-users was that IQ did drop at least 4 points — but when comparing using and non-using twins, neither showed any greater or lesser IQ decline. So, the factor making a user dumber than a non-user, in some cases, probably had more to do with things like who they hung out with. Or maybe they were just dumb to begin with.
Granted, the research was observational (the stoners performed fine on problem-solving puzzles!), and there are reams of counter-research to suggest that maybe you should keep Junior away from fried eggs. So, if you’re conflicted on the way forward, maybe take some solace in knowing that Hunter S. Thompson’s son turned out pretty OK.