Patterns of memory dysfunction in current and 2-year abstinent MDMA users

The popular recreational drug MDMA or "ecstasy" is a selective serotonin neurotoxin in many species and has been found to be associated with memory dysfunction in human beings. Recent studies suggest that this impairment persists after cessation of use for periods up to at least one year. However, there is no clear indication as yet concerning which stage of memory processing is impaired as a result of MDMA use. In the current study, 31 current MDMA users and 30 MDMA users who had been abstinent for more than two years were compared with 30 controls on the WMS-III. The results suggest that MDMA use is associated with memory dysfunction and that this dysfunction persists for up to two years after cessation of use. Importantly, the findings suggest that this memory dysfunction may be due to interference at the encoding stage of memory processing.