Marijuana impairs the brain by acting on two types of brain cell at once, a new Ottawa study shows.
Read more: http://www.ottawacitizen.com/technology/Marijuana%2Beffect%2Bbrain%2Bdoubled%2Bstudy%2Bindicates/6268015/story.html#ixzz1oXshUNiI
READ MORE: Marijuana's effect on brain doubled, study indicates.