Originally appearing at http://reason.com/blog/2011/02/17/new-study-finds-no-link-betwee. A new government-funded study finds, contrary to earlier research, that MDMA use is not associated with cognitive impairment. The study, reported yesterday in the journal Addiction, sought to address the weaknesses in comparisons that have been widely cited as evidence of brain damage caused by MDMA (a.k.a. Ecstasy): “The researchers fixed four problems in earlier research on ecstasy. First, the non-users in the experiment were members of the “rave” subculture and thus repeatedly exposed to sleep and fluid deprivation from all-night dancing—factors that themselves can produce long-lasting cognitive effects. “Second, participants were screened for drug and alcohol use on the day of cognitive testing, to make sure all participants were tested while “clean.” “Third, the study chose ecstasy users who did not habitually use other drugs that might themselves contribute to cognitive impairment. “Finally, the experiment corrected for the possibility that any cognitive impairment shown by ecstasy users might have been in place before they started using the drug. “The resulting experiment whittled 1500 potential participants down to 52 carefully chosen ecstasy users, whose cognitive function was compared against 59 closely-matched non-users, with tests administered at several stages to make sure participants were telling the truth about their drug and alcohol use.” The researchers, led by John Halpern of the Laboratory for Integrative Psychiatry, obtained a $1.8 million grant from the National Institute on Drug Abuse to clarify whether the differences in performance found in earlier studies were due to MDMA’s effects. Their conclusion: “We found little evidence of decreased cognitive performance in ecstasy users, save for poorer strategic self-regulation, possibly reflecting increased impulsivity. However, this finding might have reflected a pre-morbid attribute of ecstasy users, rather than a residual neurotoxic effect of the drug.” Halpern seems keen to put a NIDA-friendly spin on these reassuring results: “Ecstasy consumption is dangerous: illegally-made pills can contain harmful contaminants, there are no warning labels, there is no medical supervision, and in rare cases people are physically harmed and even die from overdosing. It is important for drug-abuse information to be accurate, and we hope our report will help upgrade public health messages. But while we found no ominous, concerning risks to cognitive performance, that is quite different from concluding that ecstasy use is “risk-free.”” The press release does not mention that all the risks Halpern cites are either created or exacerbated by prohibition, which makes drug quality unreliable, pushes use underground, and impedes the dissemination of reliable guidelines for responsible use. I made those points in connection with anti-rave legislation in a 2003 New York Times op-ed piece. That same year Ron Bailey examined the drug war’s corrupting impact on MDMA research. In a 2002 Reason article, I explored the link between Ecstasy and sex. Last year I analyzed a retro Ecstasy scare story in the Los Angeles Times. Reason.com shares this blog post about Dr. John Halpern’s new MAPS-supported study finding no links between long-term Ecstasy use and cognitive damage. The author makes a great point about how the real risks of Ecstasy are at least partially (and possibly entirely) the result of irrational policies prohibiting its use. By pushing Ecstasy use underground and behind closed doors, the politics of prohibition make truly responsible use practically impossible.