Neural correlates of working memory in pure and polyvalent ecstasy (MDMA) users

Working memory performance and brain activation were examined in eight abstinent people who used only MDMA (ecstasy), a group who used MDMA plus other drugs, and non-users. Pure MDMA users showed lower brain activation than controls and polyvalent users, particularly in the inferior temporal regions, angular gyrus, and striate cortex. Polyvalent users did not differ from controls. The findings suggest that altered brain activation during cognitive tasks may be primarily linked to prior MDMA use, and that concomitant use of other drugs may modify this effect.

Study at a glance

Abstract

Poor cognitive performance in ecstasy (3,4-methylenedioxymethamphetamine; MDMA) users has been related to the well-recognized neurotoxic effects of the drug upon central serotonergic and possibly also dopaminergic systems. However, concomitant use of other drugs has been a critical confound in most investigations. In this study we used an n-back task and fMRI to investigate working memory performance and related cerebral activation in eight, currently abstinent pure MDMA users and two matched groups of polyvalent MDMA users and non-users. Pure MDMA users presented lower activations than controls and/or polyvalent users, most notably in inferior temporal regions, the angular gyrus and the striate cortex, whereas polyvalent users did not differ from controls. Our results suggest that altered brain activation patterns during cognitive processing in ecstasy users may be mainly associated with prior MDMA use. Concomitant use of other drugs may modify this effect.