The impact of ecstasy upon prospective memory

The prolonged use of MDMA or 'ecstasy' has been associated with a range of memory deficits in the past, including impairments in prospective memory (PM: remembering future activities or events). What is not clear is the extent to which ecstasy users' PM problems might be underpinned by more general central executive problems within memory (CE: a set of processes underpinning the organisation and flow of information within memory). The present study extended this research by comparing ecstasy users with non-users on an objective PM task after controlling for CE processes. Methods An existing-groups design was utilised, comparing a group of regular ecstasy users with a non-user group control group as the independent factor. Scores on the PM subscale of the Prospective and Retrospective Memory Questionnaire (self-reported PM) and scores on the Cambridge Prospective Memory Test (CAMPROMPT: an objective measure of time- and event- based PM) constituted the PM dependent measures. Scores on the Dysexecutive Questionnaire (self-reported CE) and a Reverse Digit Span task (RDS: an objective CE task) constituted the CE dependent measures. Age, mood, and other drug use were also measured. Results After observing no between-group differences on age, mood, and other drug use (cigarettes, alcohol, cannabis), ecstasy users and non-users did not differ significantly on self-reported PM or CE. However, ecstasy users performed significantly worse on the CAMPROMPT and RDS than did the non-users. After controlling for RDS scores, the difference between users and non-users on CAMPROMPT disappeared. Conclusion The observation that difference between ecstasy users and non-users on the CAMPROMPT disappeared after controlling for CE performance on the RDS task suggests strongly that objective PM performance is underpinned by CE functions. The deficits on CAMPROMPT performance found in the ecstasy users must therefore have their origins in faulty CE processes. These findings will be discussed further at the conference.