Casual marijuana use may come with some not-so-casual side effects. For the first time ever, researchers at Northwestern University have analyzed the relationship between casual use of marijuana and brain changes—and found that young adults who used cannabis just once or twice a week showed significant abnormalities in two important brain structures. The study’s findings, to be published Wednesday in the Journal of Neuroscience, are similar to those of past research linking chronic, long-term marijuana use with mental illness and changes in brain development. …
