3,4-Methylenedioxymethamphetamine (ecstasy)-induced learning and memory impairments depend on the age of exposure during early development

Use of 3,4- methylenedioxymethamphetamine (MDMA; ecstasy) has increased dra matically in recent years, yet little is known about its effects on the dev eloping brain. Neonatal rats were administered MDMA on days 1-10 or 11-20 ( analogous to early and late human third trimester brain development). MDMA exposure had no effect on survival but did affect body weight gain during t reatment. After treatment, body weight largely recovered to 90-95% of contr ols. MDMA exposure on days 11-20 resulted in dose-related impairments of se quential learning and spatial learning and memory, whereas neonatal rats ex posed on days 1-10 showed almost no effects. At neither stage of exposure d id MDMA-treated offspring show effects on swimming ability or cued learning . Brain region-specific dopamine, serotonin, and norepinephrine changes wer e small and were not correlated to learning changes. These findings suggest that MDMA may pose a previously unrecognized risk to the developing brain by inducing long-term deleterious effects on learning and memory.