The occasional use of cannabis during late adolescence is not independently associated with adverse effects on cognitive abilities in young adulthood, according to longitudinal data published in the journal Drug and Alcohol Dependence. A team of investigators affiliated with the University of Colorado at Boulder assessed the impact of cannabis use on cognition, executive function, and working memory in 856 individual twins. Cannabis consumers were compared to their non-using twins in late adolescence and then again in their early twenties. Most of the cannabis consuming participants in the study reported occasional use of the substance, but not daily use. Authors found “little support for a causal effect of cannabis use on cognition. This conclusion is consistent with those from previous…
The use of cannabis during adolescence is not associated with structural brain differences in adulthood, according to longitudinal data published in the journal Drug and Alcohol Dependence. Researchers concluded, concluded, “[T]he patterns of cannabis use typically seen in community-dwelling adolescents does not appear to have lasting effects on brain structure.”
Cannabis exposure is not associated with significant changes in brain morphology in either older or younger subjects, according to a pair of newly published studies.
Cannabis use by teens is not independently linked with adverse changes in intelligence quotient or executive functioning, according to longitudinal data published online ahead of print in the journal Addiction. Investigators concluded, “Short-term cannabis use in adolescence does not appear to cause IQ decline or impair executive functions, even when cannabis use reaches the level of dependence.”
Alcohol consumption is associated with negative changes in gray matter volume and in white matter integrity, while cannabis use is not, according to data published online ahead of print in the journal Addiction.
Medical cannabis administration is associated with improved cognitive performance and lower levels of prescription drug use, according to longitudinal data published online in the journal Frontiers in Pharmacology.
It was less than a year ago when the mainstream media was chock-full of headlines like this one: ‘Brain changes associated with casual marijuana use in young adults, study finds.’
But a funny thing happened when a team of scientists from the University of Colorado and the University of Kentucky tried to replicate these results in a separate, larger sample (158 participants) of subjects after rigorously controlling for both groups’ use of alcohol. They couldn’t.
NORML’s Deputy Director today on Alternet.org addressed new media claims that cannabis use can potentially shrink the brain.
Investigators at the University College of London analyzed data from 2,612 subjects who had their IQ tested at the age of eight and again at age 15. They reported no relationship between cannabis use and lower IQ at age 15 when confounding factors such as alcohol use and cigarette use were taken into account.
Using high–resolution MRI imaging, scientists identified specific changes in particular regions of the brain that they inferred were likely due to marijuana exposure. Notably, however, these changes did not appear to be associated with any overt adverse effects in subjects’ actual cognition or behavior.