Melbourne, Australia: The use of cannabis, even long-term, is not associated with changes in the cortical surface of the brain, according to data published in the journal European Neuropsychopharmacology.
A team of investigators from Australia and the Netherlands assessed the relationship between cannabis use and brain morphology in a cohort of 261 subjects (141 cannabis users and 120 controls). Researchers reported "no significant effects on cortical surface morphology" that could be attributable to subjects' cannabis use, dependence, or age of initiation.
Authors concluded, "Our lack of finding in a well-powered study suggests that cortical surface morphology may be less associated with cannabis use than previously assumed."
The findings are consistent with other recent brain imaging studies – such as those here, here, and here – and are largely inconsistent with those of a well-publicized 2014 study purporting that even causal cannabis exposure was linked to changes in the brain in young people.
For more information, contact Paul Armentano, NORML Deputy Director, at: email@example.com. Full text of the study, "Cortical surface morphology in long-term cannabis users: A multi-site MRI study," appears in European Neuropsychopharmacology. Further information is available from the NORML fact-sheet, "Marijuana Exposure and Cognitive Performance."