The party may be over for marijuana and Ecstasy users: In several studies, scientists have weeded out the popular drugs' mental impact and found nothing to rave about.
In the one study, published in the Journal of Neurology, Neurosurgery and Psychiatry, Euphrosyne Gouzoulis-Mayfrank, M.D., a psychiatrist at the University of Technology in Germany, put 28 Ecstasy users through tests on a range of mental abilities. While users were as mentally alert as non-users, they fared far worse on measures of memory, learning and general intelligence. The more frequently they took Ecstasy, the worse they did. This is likely because Ecstasy alters neuronal function in a brain structure called the hippocampus, which helps create short-term memory.
In two other studies, published in NeuroReport, scientists at the University of Iowa took PET (positron emission tomography) scans of marijuana users' heads and found that activity in the cerebellum--the brain area that coordinates movement and Is key to awareness of time--seems to slow when smoking pot. "Having an underactive cerebellum could upset the way the brain processes information," says researcher Robert Block, Ph.D., which may hinder one's ability to learn new information.