"Favorable reports about cognitive function, memory, and concentration on the LTFU Questionnaire were consistent with findings from formal measures of cognitive function that were taken before and after psychotherapy with MDMA versus placebo, in the original study. Though reports from actual testing are more reliable than reports of perceived cognitive function, this long-term self-reported evidence is still important, because of the controversy surrounding theories that there are potential risks of neurocognitive decline resulting from MDMA administration, as has been suggested by animal studies and some retrospective studies in recreational drug users (Thomasius et al., 2006; Kalechstein et al., 2007; Laws and Kokkalis, 2007; Zakzanis et al., 2007; De Sola Llopis et al., 2008; Jager et al., 2008; Schilt et al., 2008; Brown et al., 2010; Kish et al., 2010; Verbaten, 2010) and one prospective study (Schilt et al., 2007)."

Source

Mithoefer, Michael C., et al., "Durability of improvement in posttraumatic stress disorder symptoms and absence of harmful effects or drug dependency after 3,4-methylenedioxymethamphetamine-assisted psychotherapy: a prospective long-term follow-up study," Journal of Psychopharmacology, published online Nov. 20, 2012, DOI: 10.1177/0269881112456611.
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