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Casual Marijuana Use Linked to Brain Abnormalities

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The April 15, 2014 online edition of The Journal of Neuroscience published a study by Northwestern University which shows that recreational marijuana use (at least one time per week) by young adults (ages 18-25) results in altered brain changes. This MRI-scan study showed the degree of brain abnormalities in these regions and its direct relationship to the number of joints a person smoked per week. The more joints a person smoked, the more abnormal the shape, volume and density of the brain regions.


According to the Northwestern University press release, “This study raises a strong challenge to the idea that casual marijuana use isn’t associated with bad consequences,” said corresponding and co-senior study author Hans Breiter, M.D. He is a professor of psychiatry and behavioral sciences at Northwestern University Feinberg School of Medicine and a psychiatrist at Northwestern Memorial Hospital. – “Some of these people only used marijuana to get high once or twice a week,” Breiter said. “People think a little recreational use shouldn’t cause a problem, if someone is doing OK with work or school. Our data directly says this is not the case.”  

Read more studies on the negative effects of marijuana use on the brain at the bottom of this link.