Heavy use of the drug Ecstasy, or MDMA, can lead to persistent problems in remembering what is seen and heard, according to a study appearing in the December issue of Neurology. According to researchers from Johns Hopkins University, Bayview Medical Center, the memory impairment increases with the amount of drug taken and lasts at least two weeks after stopping use. These memory problems appear to be related to the damage Ecstasy does to particular brain cells that use the chemical serotonin for communication.
These findings follow closely on a study published in the October 31 issue of The Lancet by some of the same scientists showing that frequent Ecstasy use damages the brain's ability to use serotonin, and that this brain change lasts at least for three weeks after stopping use.
Short for methylenedioxymethamphetamine, MDMA is an amphetamine derivative long known to be neurotoxic in animals. In recent years use of the drug has been on the rise, in part because of the popularity of large, organized, all night social gatherings known as "raves." Many young adults who use the drug take doses similar to those that cause brain damage in animals.
"These studies sound an alarm to young people and their parents about the serious dangers of this party drug," says Alan I Leshner, Ph.D., Director of the National Institute on Drug Abuse (NIDA), National Institutes of Health, which funded the research. "Not only does Ecstasy cause problems while someone is using the drug, but it damages the brain in ways that can interfere with normal learning and memory that continue weeks after one stops taking it."
The Johns Hopkins researchers compared 24 MDMA users with 24 control subjects. After being matched for age, gender, education, and verbal intelligence, participants were given several standardized tests for memory. The results showed that the "heavy" users?individuals who used at least 400 milligrams of MDMA per month?had greater impairment in verbal memory, which is the ability to remember information that is heard. They also had delayed visual memory, difficulty in recalling viewed material. These difficulties increased with the amount of MDMA used. Women, however, were less susceptible than men to MDMA dose-related decreases in memory.
At the same time, the researchers indirectly assessed brain serotonin function through looking at one of its metabolites (5-HIAA) in spinal fluid. Notes study author Karen I. Bolla, Ph.D., "We found that the more MDMA a person reported using, the lower level of 5-HIAA. In addition, people with the lowest levels of 5-HIAA showed the most trouble with visual memory tests. This suggests that Ecstasy has a dose-related effect on serotonin activity which, in turn, affects memory in humans."
MDMA use has been reported most frequently among young adults and adolescents at clubs, raves, and rock concerts in Atlanta, Miami, St. Louis, Seattle, and areas of Texas. In 1996, NIDA and the University of Michigan Institute for Social Research began collecting data on MDMA use among 8th, 10th and 12th graders. Rates of use remained relatively stable from 1996 to 1997. In 1997, 6.9 percent of 8th graders had used MDMA at least once in their lives.