In brief
- A pilot study of 48 healthy volunteers associates four 15 µg microdoses of LSD with improved sustained attention in women.
- No comparable improvement appeared in men, and results regarding information processing and working memory were less conclusive.
- This is a re-evaluation of a previous study presented at a conference; the authors themselves call for confirmation with a larger participant pool.
A team from Maastricht University has presented a small study on LSD microdosing at the ECNP congress in Munich. Women who received LSD experienced fewer lapses in attention compared to those who received a placebo. No similar effect was observed in men.
Methodology and Participants
The research, led by Iva Totomanova, reanalyzed a completed randomized, double-blind, placebo-controlled trial. The study involved 48 healthy volunteers, 24 of whom were women, with an average age of 36.9 years. Each participant was randomly assigned either a placebo or four 15-microgram doses of LSD spread over two weeks. According to the press release, typical psychedelic effects usually emerge above 60 micrograms, making this a significantly lower dose.
Researchers measured sustained attention, information processing, and working memory through tests conducted at baseline, after the first dose, after the fourth dose, and during a follow-up period.
Findings
The primary result concerns sustained attention in women. With LSD, their average reaction time was 308 milliseconds compared to 335 milliseconds with the placebo—about 8% faster. Attention lapses dropped from an average of 4.7 with the placebo to 2.3 with LSD. This reduction was observed after the first dose, after repeated dosing, and at follow-up.
There was no comparable improvement in men. In the other two tasks—information processing and working memory—the results were less clear, according to the lead researcher.
Implications
These findings should be interpreted with caution. Totomanova emphasizes that this is a small pilot study that must be confirmed in a larger population, and that the data does not prove that low-dose LSD improves general cognition or that women respond better than men. As a re-analysis, the study was not originally designed to compare sexes, and the press release does not indicate which journal will publish the findings or whether it has undergone peer review. The team suggests that future work should measure blood hormone levels and account for menstrual cycle phases and contraceptive use.
Mikkel Højlund of the University of Southern Denmark, who was not involved in the study, notes that while the study is small and involves several variables, it warrants further investigation on a larger scale.
This finding adds to a mixed body of evidence. Our coverage of a 2026 review on cognition noted that, overall, microdosing did not show clear improvements, suggesting that individual differences—such as sex—are a lead to be investigated rather than a definitive conclusion. For broader context, you can consult our Psychedelics Guide on microdosing.
Source
- ECNP. LSD microdosing: Study indicates it makes women’s attention sharper, but no improvement in men. Press release from the 39th ECNP Congress (Munich), via EurekAlert, October 11, 2026.
Educational content written from a harm reduction perspective and with respect for individual freedom. It is not a substitute for advice from a healthcare professional and is not intended to encourage or condemn any drug use.
