TUESDAY, Oct. 30, 2001 (HealthDayNews) -- If you can't remember the last time you took ecstasy, don't be surprised. The increasingly popular rave and club drug may be wreaking long-term havoc with your memory, contends a new study.
Researchers from Holland say people who've used ecstasy, including both recent users and those who haven't used the drug in more than a year, have more problems remembering words than people who have not used the drug. The researchers also say that brain images of people who've used ecstasy show a decreased density of the cells involved in memory.
But a Johns Hopkins Medical School researcher says the memory problems could have been caused by something else, such as marijuana use, and more study is necessary to confirm the findings.
The research stems from a doctoral thesis that looked at the potential harmful effects of ecstasy use on brain cells, says Dr. Liesbeth Reneman, a staff radiologist at the Academic Medical Center in Amsterdam, in an e-mail interview.
Ecstasy, the popular name for MDMA (3,4-methylenedioxymethamphetamine), is a synthetic drug that produces both stimulant and hallucinogenic effects. Ecstasy also goes by the street names Adam, XTC, hug, beans and love drug. Its chemical structure is similar to methamphetamine and mescaline, drugs known to cause brain damage, says the National Institute on Drug Abuse.
Roughly 1.3 million American students in grades 8 to 12 have tried ecstasy at least once, and 450,000 currently use it, says a recent institute survey.
It's also popular in Holland, Reneman says, and "some studies suggest that the recreational use of this drug is increasing in every Westernized county."
Scientists have known for some time that ecstasy affects the type of brain cells that use the chemical serotonin to communicate with other cells, she says. To see if the drug had an effect on memory, she put 22 recent ecstasy users, 16 ex-users and 13 people who did not use drugs through a battery of brain imaging and verbal memory tests. All participants, who were aged 18 to 45, agreed not to use any drugs for three weeks before the study.
Brain scans of those who had stopped using ecstasy a year before the study showed that five neurons specifically linked to memory function did not differ from those of people who had not used the drug, Reneman says. Recent users showed fewer cells.
Participants who had used ecstasy, either recently or in the past, performed poorly on verbal memory tests compared with non-drug users, the study says.
"Our findings indicate that individuals who stopped using ecstasy had a deficit in memory similar to that of current users, and that higher lifetime doses of MDMA are associated with greater losses in verbal memory function," Reneman says. Details appear in the October issue of the Archives of General Psychiatry.
Reneman says she's not sure why the study found no observable brain cell changes in those who had stopped using ecstasy, even though they continued to show memory problems. "This is a very interesting finding, and there are several possible explanations," she says.
"Memory testing could be more sensitive to MDMA's neurotoxic effects," she suggests. "Or, the [five neurons] may still be decreased in the brain regions which are very important for memory performance, such as the hippocampus, for instance, which we unfortunately could not study with [the brain-imaging technique] due to it's relatively low resolution." The hippocampus is a structure in the brain involved in the storing memories.
But other doctors see a possible problem with the study.
"The brain-imaging technique these researchers used has never been able to detect the type of damage they thought they were seeing, particularly in the regions where they thought they saw this damage," says Dr. Una McCann, associate professor of psychiatry at Johns Hopkins Medical School, in Baltimore, whose commentary is published along with the study.
Reneman uses cognitive damage "as sort of an indirect measure of the brain damage caused by ecstasy," McCann says. "We have to be cautious about these types of indirect measures because there are many possible reason for cognitive problems."
For instance, she says marijuana use has been shown to cause short-term memory problems.
"We brought marijuana up because a lot of ecstasy users are also shown to be marijuana users," McCann says. "What we should be doing is continuing these studies where we can directly measure and look at a variety of functions including cognitive, sleep, aggression and neuroendocrine function."
What To Do: For more information on ecstasy and memory, go to the National Institute on Drug Abuse online or check ScienceNet.
