By ABIGAIL SULLIVAN MOOREOCT. 29, 2014
The gray matter of the nucleus accumbens, the walnut-shaped pleasure center of the brain, was glowing like a flame, showing a notable increase in density. “It could mean that there’s some sort of drug learning taking place,” speculated Jodi Gilman, at her computer screen at the Massachusetts General Hospital-Harvard Center for Addiction Medicine. Was the brain adapting to marijuana exposure, rewiring the reward system to demand the drug?….
Evidence of long-term effects is also building. A study released in 2012showed that teenagers who were found to be dependent on pot before age 18….
“Working memory is key for learning,” Dr. Breiter said. “If I were to design a substance that is bad for college students, it would be marijuana.”
A Harvard-Northwestern study has found differences between the brains of young adult marijuana smokers and those of nonsmokers. In these composite scans, colors represent the differences — in the shape of the amygdala, top, and nucleus accumbens. Yellow indicates areas that are most different, red the least. Credit: The Journal of Neuroscience