Marijuana use may affect decision-making areas in teen brains

Giving adolescent rats a pot-like compound damaged protective 'nets' around nerve cells

Using a marijuana-like drug during adolescence may damage decision-making structures in the brain, a new study finds.

Jolygon/iStockphoto

SAN DIEGO, Calif. — Teen use of marijuana may change the brain in key decision-making areas. That’s the finding of a new study in rats.

“Adolescence is a dangerous time to be insulting the brain,” says Eliza Jacobs-Brichford. This, she adds, is especially true for use of pot and other “drugs of abuse.”

Jacobs-Brichford works at the University of Illinois at Chicago. As a behavioral neuroscientist, she studies links between the brain and behavior. In the new study, her team gave adolescent rats a chemical that mimics the effects of marijuana. Later, the researchers found changes in parts of the brain involved in making decisions.

Normally, many of the affected cells are covered by sturdy webs. These are called perineuronal (PAIR-ih-nurr-OHN-ul) nets. The rigid structures help stabilize links between cells. But adolescent male rats treated with the drug had fewer nerve cells covered by the protective nets. The drug exposure didn’t seem to affect the nets in female rats.

Jacobs-Brichford presented her team’s findings November 7. She spoke, here, at the annual meeting of the Society for Neuroscience.

Laura Sanders is the neuroscience writer. She holds a Ph.D. in molecular biology from the University of Southern California.

More Stories from Science News for Students on Brain