In the first stage, the scientists analyzed MRI data from the brains of adolescents under 16 who used marijuana. They found a finer structure of the cerebral cortex. This data was very useful, but did not allow any conclusions to be drawn about the causal relationship between cannabis and brain cell function, so the scientists turned to preclinical models. The results are published on the website of the University of Montreal.
Experiments showed that tetrahydrocannabinol (THC) altered the expression of genes that affect the structure and function of synapses and dendrites, resulting in signs of atrophy that explain the thinning of the cortex in adolescents.
Among the main consequences of cortex thinning in the developing brain, scientists highlight difficulties in learning and interacting with people, as well as coping with new situations. “In other words, it makes the brain of a young person vulnerable to everything that will happen to it in later life,” concluded the author of the study, Thomas Paus.
In another study, scientists previously found that cannabis leaves a unique mark on DNA. It was found that smoking marijuana affects mitochondrial and immune function and can alter biological processes in the body.