LSD Microdosing Shows Attention Benefits for Women But Not Men in Pilot Study

Researchers from the University of Maastricht presented their findings at the European College of Neuropsychopharmacology congress in Munich. They examined how very small amounts of lysergic acid diethylamide affect cognitive tasks. The results were shared as part of a pilot study focused on sex-specific responses to psychedelics.

The trial involved 48 healthy volunteers split evenly between women and men. Participants had an average age of 36.9 years and were randomly assigned to groups. Some received a placebo while others took four low doses of LSD over two weeks.

Each dose contained 15 micrograms of the drug, which is well below the level needed for full psychedelic effects. Typical experiences with such drugs usually require doses greater than 60 micrograms to appear. This method ensured participants did not experience hallucinations during the testing period.

Neither the people taking the drug nor the researchers knew who received LSD until after the study finished. They tracked three areas of mental performance including working memory and information processing speed. The most notable changes appeared in tests measuring sustained attention.

Women who took the placebo tended to have slower reaction times than men on the same task. However, women given low-dose LSD responded about 8 percent faster than those on the placebo. They also experienced an average of 2.3 attention lapses compared to 4.7 lapses for the women taking the placebo.

Men receiving the same low doses did not show comparable improvements in their reaction times. The pattern of faster responses and fewer lapses in women appeared after the first dose. This benefit remained consistent during repeated dosing and at follow-up assessments.

Lead researcher Iva Totomanova explained that LSD improved how women sustain attention in certain tasks. She noted the work does not show that low-dose LSD generally improves cognition for everyone. Effects may depend on the person and the specific circumstances of use.

Results for information processing and working memory were not as clear-cut in this study. Previous studies might have missed these sex-related effects by pooling data from men and women. The researchers suggest personalized approaches may be needed for psychedelic treatments.

Because this work is a reanalysis of an earlier dataset, the authors say results need confirmation in larger populations. Future research should look at hormone concentrations and menstrual phases to understand why some people respond differently. This could help explain why individuals vary in their responses to psychedelics.

Dr. Mikkel Højlund from the University of Southern Denmark commented independently on the findings. He stated that testing microdosing in a proper research context is important to advance knowledge. The study merits further work on a bigger scale despite its small size.