Just one or two joints seem to change the structure of the brain, say researchers from universities around the world, led by senior author and University of Vermont professor of psychiatry Hugh Garavan, PhD, and first author and former UVM postdoctoral fellow Catherine Orr, PhD.
 
The study is part of a long-term European effort called IMAGEN, which has collected brain images from 2,000 children in Ireland, France, and Germany, starting when they were age 14 and continuing through age 23.
 
Researchers compared the brain images of 46 children age 14 who reported having used marijuana once or twice with those of children that age who had not used the drug. The images of the marijuana triers showed greater brain volume in areas with cannabinoid receptors. The biggest differences were in the amygdala, involved in fear and other emotions, and the hippocampus, the site of memory development and spatial abilities.
 
“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,” says Dr. Garavan.
 
It is unclear what the extra gray matter in these brain areas means. Normally at age 14, the brain is refining its synaptic connections to make it thinner, not thicker. Dr. Garavan says one possibility is that initial marijuana use in this age group may be disrupting that “pruning” process.
 
The new findings open a new area of focus for future research.
 
Read study abstract here.

Source:  The Marijuana Report  16.01.2019