Preliminary evidence of hippocampal dysfunction in adolescent MDMA ("ecstasy") users: possible relationship to neurotoxic effects

Abstract

Rationale: 3,4-Methylenedioxymethamphetamine (MDMA or ecstasy) is a potent and selective serotonin neurotoxin whose use is growing among adolescents. Although cognitive deficits among adult MDMA users are well documented, little is known of the cognitive and brain functional sequelae of MDMA use during adolescence.

Objective: We tested for evidence of cognitive deficits and changes in brain function in a pilot sample of adolescent MDMA users, who were compared with adolescent non-users of MDMA.

Methods: Selective and divided attention and verbal working memory were examined in six adolescent MDMA users and six non-users of MDMA who were similar in age, gender, IQ, and other substance use. Brain function was assessed during performance of the working memory task using functional magnetic resonance imaging (fMRI).

Results: MDMA users had significantly prolonged reaction times during tests of selective and divided attention, and failed to deactivate the left hippocampus normally during high verbal working memory load.

Conclusions: MDMA use in adolescence may be associated with cognitive impairments and dysfunction of inhibitory circuits within the hippocampus. Further work is urgently needed to delineate the developmental impact and long-term functional and clinical significance of MDMA use during adolescence.