086 | Psychedelic microdosing: Results from a double-blind placebo-controlled study

Cognition, Behavior, and Memory

Author: Federico Cavanna | Email: f.cavanna@gmail.com

Federico Cavanna , Stephanie Müller , Laura A. De la Fuente , Federico Zamberlan , Matías Palmucci , Lucie Janeckova , Martin Kuchar , Carla Pallavicini , Enzo Tagliazucchi

1° Computational Cognitive Neuroscience Lab, Departamento de Física, UBA, CONICET, Argentina.
2° Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia (FLENI), Argentina.
3° Forensic Laboratory of Biologically Active Substances, UCT, Prague, Czech Republic
4° Latin American Brain Health Institute (BrainLat), Universidad Adolfo Ibañez, Santiago de Chile, Chile.

The use of low sub-perceptual doses of psychedelics, known as ‘microdosing,’ has gained popularity recently. While anecdotal reports suggest various benefits, the lack of placebo-controlled studies limits our understanding of microdosing and its effects. Traditional lab research may also miss the motivation of microdosers, potentially underestimating positive impacts on creativity and cognition. We recruited 34 participants beginning psilocybin mushroom (Psilocybe cubensis) microdosing. In a double-blind placebo-controlled study, we examined the acute and short-term effects of 0.5g of dried mushrooms on subjective experience, behavior, creativity, perception, cognition, and brain activity. Acute effects were significantly stronger for the active dose, but only when participants correctly identified their condition. These changes coincided with reduced theta band EEG power and consistent Lempel-Ziv signal complexity. Other measurements showed minimal effects, with slight cognitive impairment. Low psilocybin doses yield noticeable effects and altered EEG patterns but lack evidence for improved well-being, creativity, or cognition. Our findings suggest that expectations may contribute to anecdotal microdosing benefits.