Purpose: Brain imaging, neurocognitive: To examine the effects of MDMA use on the hippocampus with MRSI, to explore MRSI as an imaging tool, to test the temporal reliability of MRS measurements, and to examine cognitive function in ecstasy users.

Design: Non-experimental (retrospective) between subject / within-subject design, with drug use history as a between-groups factor (self-reported ecstasy use versus no reported drug use) and scan time (two separate scans 3 - 7 days apart) as a within-subjects variable. All participants underwent 2 [1H]-MRSI scans and completed measures of cognitive function.

Subjects: 5 ecstasy users and 5 non-user controls, probably residing in or near the Mannheim (Germany) area. No information is provided concerning recruitment of ecstasy users or controls. Matching - Ecstasy users and non-users were matched for age.

Criteria for Inclusion, Ecstasy Users - Having reported using at least 100 ecstasy tablets in a lifetime. Non-Users - Age-matched with ecstasy users, and no history of substance abuse (apparently meaning no reported use of drugs, and specifically never having used ecstasy). Both Groups - No major psychiatric illnesses, as assessed via BDI and PANSS, and abstinence from any psychoactive drugs on the study day, with abstinence verified through self-report only.

Drug Use Parameters - No information provided on the average lifetime use of ecstasy or on average dose per use. The range of lifetime ecstasy use was 120-350 tablets. No information is provided on average duration of ecstasy use or frequency of use; duration of use, in months, ranged from 36 - 72 months. Range of time since last use, in days, was 27-120 days, with no information provided on average time since last use. Other Drugs - No information is provided concerning use of other drugs.

Group Demographics and Matched Variables - The authors matched ecstasy users with non-user controls. Gender, as M/F ratio. No information provided on gender composition of either group. Age - Ecstasy users were, on average, 25.7 +/- 2.7 years old. Non-users were, on average, 26.6 +/- 2.9 years old.

Measures: Imaging - 2 [1H]-MRS scans were performed with a 1.5 T scanner, with the second scan occurring 3 - 7 days after the first scan. Concentrations of N-acetylaspartate (NA), creatine (Cr), and choline (Ch) were made in L and R hippocampi, with data transformation and measurements performed by an experimenter blind to participant's condition.

Memory and Executive Function - Executive function was measured through the Wisconsin Card Sorting Test (WCST). Working memory was measured via the "Working memory" sub-test in the TAP (German language neurocognitive test battery).

Analyses: Imaging - Hippocampal values of NA, Cr and Ch were compared across ecstasy users and non-users with two-tailed t tests. Scans were assessed for test-retest reliability via student's t test performed with first and second scan.

Executive function and working memory - No information is provided on analysis of WCST or TAP working memory scores. (It is possible that these were used as screening tools.) It is possible that they were analyzed via t-tests.

Results - Significant Differences: None. There was a trend for lower Cr in ecstasy users versus non-users, but this was not statistically significant.

Results - No Differences Found: Imaging - There were no differences in NA concentration in L or R hippocampus of ecstasy users and non-users. Ecstasy users and non-users did not have significantly different concentrations of Cr and Ch compounds in hippocampus. There were no significant differences between the first and the second scan for either group; intra-subject variability was low (within 1% to 5.8%).

Executive Function and Working Memory - There were no significant differences between WCST performance in ecstasy users and non-users. There were no significant differences in performance on the TAP working memory sub-test, with ecstasy users and non-users performing similarly.

Overall Effects: There were no measurable differences in amount of hippocampal NA, Cr or Ch in 5 ecstasy users, as compared with 5 non-user controls, where controls were individuals reporting no past use of ecstasy and possibly no use of any illicit drugs. Only a trend for lower creatine was found in ecstasy users, but this did not reach statistical significance. This method of MRS had low intra-subject variability, as indicated by within-subject comparisons of 2 scans. Ecstasy users and non-user controls performed similarly on the WCST, a measure of executive function, and a working memory sub-test of the TAP.