University of Vermont researchers found that "even small amounts" of marijuana changes teen brains.
"You're changing your brain with just one or two joints. Most people would likely assume that one or two joints would have no impact on the brain," UVM Professor of Psychiatry Hugh Garavan said in a press statement regarding the implications of the study.
What the increased brain matter volume means was not part of the study. But Garavan explained in the statement that the enlargement of gray matter is in opposition to normal adolescent development....