Category: IQ

Yet Another Study Finds That Cannabis Use Is Not Independently Linked With IQ Decline

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.”

Twin Study: Marijuana Use Has No Direct Effect On IQ

The cumulative use of cannabis by adolescents has no direct effect on intelligence decline, according to longitudinal data published today in the Proceedings of the National Academy of Sciences. Investigators concluded: “In the largest longitudinal examination of marijuana use and IQ change, … we find little evidence to suggest that adolescent marijuana use has a direct effect on intellectual decline.”

Study: Cannabis Use Not Predictive Of Lower IQ, Poorer Educational Performance

Marijuana use by adolescents is not associated with lower IQ or poorer educational performance once adjustments are made for potential confounders, specifically cigarette smoking, according to longitudinal data published online ahead of print in the Journal of Psychopharmacology. Researchers concluded, “In summary, the notion that cannabis use itself is causally related to lower IQ and poorer educational performance was not supported in this large teenage sample.”

Latest Media Buzz Regarding Pot’s Potential Impact On IQ Misses The Bigger Issue

The mainstream press has been abuzz in recent days regarding the findings of a recent study suggesting that early-onset, persistent cannabis exposure by those under age 18 could potentially pose adverse effects on intelligence quotient. Yet, absent from the media’s discussion of the study — a discussion that has even included some fairly critical reviews of the study’s methodology (See here and here for just two examples.) — is any talk of the role that marijuana prohibition plays in inadvertently steering young people toward cannabis, an issue I address in […]