A recent study has provided the first direct evidence that chronic use of Ecstasy causes brain damage in people. Using advanced brain imaging techniques, it was found that Ecstasy harms neurons that release serotonin, a brain chemical thought to play an important role in regulating memory and other functions. In a similar study, it was found that heavy Ecstasy users have memory problems that persist for at least 2 weeks after they have stopped using Ecstasy.
A study was conducted using several standardized memory tests on 24 MDMA users who had not used the drug for at least 2 weeks, and similarly conducted on 24 people who had never used Ecstasy. Both groups were matched for age, gender, education, and vocabulary scores. The study found that, compared to the nonusers, heavy Ecstasy users had significant impairments in visual and verbal memory. As had been found in the brain imaging study, Ecstasy's harmful effects were dose-related. The more Ecstasy people used, the greater difficulty they had in recalling what they had seen and heard during testing.
Findings from another study suggest that Ecstasy use may lead to impairments in other cognitive functions besides memory, such as the ability to reason verbally or sustain attention.
Ecstasy users may also find they have a dry mouth, blurred vision, wiggling eyes and the chills. Involuntary muscular activity and muscular tension sometimes occurs, resulting in twitches and cramps. The lower face muscles are especially prone to this, causing jaw clenching and teeth grinding. Hence, chronic Ecstasy users experience various severe dental maladies, namely cracking enamel, worn teeth and jaw problems. Pacifiers and retainers are used by Ecstasy users to attempt to combat this problem. A recent British study found that 60 percent of Ecstasy users examined had worn their teeth through the enamel and into the underlying dentine. The Ecstasy user's decay was nearly five times worse than that of the average Brit.