Verbal working memory deficits in current and previous users of MDMA

Previous research suggests that MDMA users are impaired in various aspects of cognitive functioning, however, it remains unclear whether they might experience deficits in established measures of verbal working memory functioning. In the present study current and previous MDMA users were compared with non-users on verbal working memory measures including reading and computation span. Both user groups were found to be impaired on the computation span measure while current users also exhibited impairment in reading span. The MDMA-related deficit on the computation span measure remained significant following the introduction of statistical controls for the potentially confounding effects of cannabis and other drugs. The results are discussed in the context of recent research on executive processes. It is suggested that MDMA may produce differential effects on specific components within a fractionated executive system.