After studying the effects of marijuana on the brain, American scientists have disproved the previous findings that weed may cause a decline in intelligence in teenagers.
The researchers from the University of Southern California, Los Angeles, carried out the largest longitudinal investigation on pot and the teens’ IQ change. They examined more than 3,000 American adolescents, including twins, measuring the brain activity decline of cannabis smokers compared to non-smokers.
Previously, cannabis consumption in adolescence was associated with the decline in memory, intelligence, attention, and verbal ability. However, it remains unclear if it is indeed marijuana that leads to cognitive impairment, or whether there are confounding factors.