Researchers at the University of Sydney in Australia found that the chemical in marijuana affects adult and adolescent rats differently. In particular, adolescent rats lost more long and short-term memory.

Dr. Ian McGregor and his colleagues tested the rats' memories right after they ingested the drug, and again after all traces of it had left their bodies. The adolescent rats had deeper memory impairment. In addition, the adult rats avoided the "room" where the marijuana had been "served," but the teen rats did not.

"Cannabis produces much greater long-term changes in adolescent than adult rat brains," Dr. McGregor said.

This study appears in the journal Neuropsychopharmacology.

Labels: brain_damage, marijuana, memory