Microevidence for microdosing with psilocybin mushrooms: a double-blind placebo-controlled study of subjective effects, behavior, creativity, perception, cognition, and brain activity
Federico Cavanna, Stephanie Müller, Laura Alethia de la Fuente, Federico Zamberlán, Matías Palmucci, Lucie Janeckova, Martin Kuchař, Carla Pallavicini, Enzo Tagliazucchi
bioRxiv (Cold Spring Harbor Laboratory) December 7, 2021 preprint DOI: 10.1101/2021.11.30.470657 via OpenAlex
Summary
AI-generated from the abstractA double-blind placebo-controlled trial tested the effects of a low (0.5 g) sub-hallucinogenic dose of dried psilocybin mushrooms in 34 individuals planning to microdose. Acute subjective effects were significantly stronger with the active dose than with placebo, possibly due to unblinding. For other measures—including creativity, perception, cognition, and brain activity—the results were null or showed a trend toward cognitive impairment and, in electroencephalography, reduced theta band spectral power. These findings suggest that expectation effects may account for some of the anecdotal benefits people report from microdosing psilocybin.
Study at a glance
| Characteristics | Randomized controlled trial Placebo-controlled Double-blind |
|---|---|
| Sample size | 34 |
| Population | Individuals planning to microdose with psilocybin mushrooms |
| Dose | 0.5 g dried mushrooms |
| Topics | Psilocybin |
| Keywords | Placebo Psychology Hallucinogen Cognition |
| Citations | 8 |
| Key finding | Expectation effects may explain at least some of the anecdotal benefits attributed to microdosing with psilocybin mushrooms, as the active dose produced stronger acute effects but null or impairing effects on other measures. |
Abstract
Abstract The use of low sub-hallucinogenic doses of psychedelics (“microdosing”) has gained popularity in recent years. Although anecdotal reports claim multiple benefits associated with this practice, the lack of placebo-controlled studies limits our knowledge of microdosing and its effects. Moreover, research conducted in laboratory settings might fail to capture the motivation of individuals engaged in microdosing protocols. We recruited 34 individuals planning to microdose with psilocybin mushrooms ( Psilocybe cubensis ), one of the materials most frequently used for this purpose. Following a double-blind placebo-controlled design, we investigated the effects of 0.5 g dried mushrooms on subjective experience, behavior, creativity, perception, cognition, and brain activity. The reported acute effects were significantly more intense for the active dose compared to the placebo, which could be explained by unblinding. For the other measurements, we observed either null effects or a trend towards cognitive impairment and, in the case of EEG, towards reduced theta band spectral power. Our findings support the possibility that expectation effects underlie at least some of the anecdotal benefits attributed to microdosing with psilocybin mushrooms.