Frequent marijuana use leads to memory problems, low IQ in teens

A new study has revealed that frequent marijuana use can lead to cognitive decline, poor attention and memory, and decreased IQ in teenagers and young adults.

Krista Lisdahl, director of the brain imaging and neuropsychology lab at University of Wisconsin-Milwaukee, said that it needs to be emphasized that regular cannabis use, which we consider once a week, is not safe and may result in addiction and neurocognitive damage, especially in youth and when considering legalization, policymakers need to address ways to prevent easy access to marijuana and provide additional treatment funding for adolescent and young adult users.

She also recommended that legislators consider regulating levels of tetrahydrocannabinol, or THC, the major psychoactive chemical in marijuana, in order to reduce potential neurocognitive effects.

The scientists said that Brain imaging studies of regular marijuana users have shown significant changes in their brain structure, particularly among adolescents.

Abnormalities in the brain's gray matter, which is associated with intelligence, have been found in 16- to 19-year-olds who increased their marijuana use in the past year and these findings remained even after researchers controlled for major medical conditions, prenatal drug exposure, developmental delays and learning disabilities.