Neuropsychological function in ecstasy users: a study controlling for polydrug use

Abstract

Rationale: A number of studies have compared ecstasy users to control groups on various measures of neuropsychological function in order to determine whether ecstasy use results in lasting cognitive deficits. However, few of those studies controlled adequately for non-ecstasy illicit drug use. Objective: The aim of this study was to investigate neuropsychological function in chronic ecstasy users while controlling for polydrug use. Methods: Neuropsychological function was assessed in four groups-30 current 3,4-methylenedioxymethamphetamine (MDMA) users with a little history of illicit drug use other than ecstasy and cannabis, 30 polydrug controls, 30 drug-naïve controls and 20 ex-MDMA users-using a battery of wellvalidated, computerized neuropsychological tests. The battery focused on memory, executive function, impulsivity and risk-taking. Results: Few differences were apparent between the groups, and on no measure were the current MDMA users impaired significantly relative to the polydrug controls. However, within the current MDMA users, questionnaire-measured impulsivity correlated with performance on a number of tests-a relationship that was not apparent in the controls. Conclusions: These data highlight the complexity in understanding the current ecstasy literature and suggest that some individuals may be particularly vulnerable to cognitive impairment following chronic use. Although no differences were identified between the current MDMA users and the controls, trait impulsiveness was significantly correlated with impairment on a number of neuropsychological outcome measures in the MDMA users, but not in the controls. These data suggest that impulsive individuals may be those most at risk for the development of cognitive impairment following chronic ecstasy use.

Elevated Impulsivity and Impaired Decision-Making in Abstinent Ecstasy (MDMA) Users Compared to Polydrug and Drug-Naïve Controls

“…However, we note the statistical association between discrimination between gains and losses on the one hand, and high reflection impulsivity as measured by the MFFT20 on the other hand, in the ecstasy users, is consistent with the possibility that their altered decisionmaking is one manifestation of a tendency to respond without fully sampling all of the information relevant to the choice. This finding is substantiated by a recent study of the risky decision-making in current ecstasy users, ex-users users, polydrug controls, and drug-naive controls using a relatively less sensitive version of the task used in the present study in which the probability of good outcomes varied between 0.8 and 0.2 rather than 0.66 and 0.33 (Roiser et al, 2005). The samples were carefully matched for polydrug use and indicated only modest evidence of neuropsychological deficits in those participants who were currently using ecstasy.…”

The neuropsychology of ecstasy (MDMA) use: a quantitative review

“…For instance, several researchers have repeatedly illustrated memory impairment in abstinent MDMA users in both prolonged (e.g., McCardle et al, 2004;Roiser et al, 2007) and recent samples (e.g., Bayen and Rosenberg, 2006;Smith et al, 2006). For example, Krystal et al (1992) assessed nine former users of MDMA on a battery of neuropsychological measures, and found their performance to be significantly below average on tests of immediate and delayed recall of prose passages.…”

Neurocognitive function in current and ex-users of ecstasy in comparison to both matched polydrug-using controls and drug-naïve controls

“…A recent UK study by Roiser et al (2007) investigated cognitive function in 30 current and 20 ex-ecstasy users (abstinent for at least 1 year) compared with 30 polydrug controls (well matched for the use of other recreational drugs) and 30 drug-naïve controls. Interestingly, no significant differences were found between the three drugusing groups on performance on a variety of tests assessing working memory and decision-making.…”