Addictive is as addictive does

Despite user proclamations about harmlessness, biochemically speaking heavy marijuana use leads to the same reduced dopamine release that is seen in other addictions. Anissa Abi-Dargham, professor of psychiatry at Columbia University Medical Center, New York, USA, has demonstrated, using positron emission tomography (PET), lower dopamine release in the striatum, a brain region associated with working memory, impulsive behavior, and attention. "In light of the more widespread acceptance and use of marijuana, especially by young people, we believe it is important to look more closely at the potentially addictive effects on key regions of the brain,"€ she says.