Cognitive and Subjective Effects of Psilocybin Microdosing: Results from Two Double-Blind Placebo-Controlled Longitudinal Trials
This set of two randomised, double-blind, placebo-controlled trials (n=141) investigated the longitudinal effects of microdosing psilocybin truffles on cognition and well-being in semi-naturalistic settings. Contrary to anecdotal reports, the study finds no significant improvements in cognitive control, memory, social cognition, or subjective well-being compared with placebo.
Authors
- Prochazkova, L.
- Marschall, J.
- Lippelt, D. P.
Published
Abstract
Objective
Microdosing psychedelics has been widely reported to enhance focus and problem-solving, sparking interest in its potential to treat attentional disorders such as ADHD. However, existing studies largely rely on anecdotal evidence and lack adequate placebo control.
Methods
This study contributes to the literature by examining the longitudinal effects of microdosing psilocybin truffles in two randomized, double-blind, placebo-controlled trials conducted in semi-naturalistic settings. We assessed multiple domains, including cognitive control, memory, social cognition, subjective well-being and subjective experiences using mix of quantitative and qualitative methods.
Results
Contrary to expectations, microdosing did not significantly affect behavioral or subjective measures compared to placebo. While some initial effects were observed in social cognition, mood, and self-reported cognitive flexibility, these did not remain significant after correcting for multiple comparisons. Regardless of condition, participants predominantly reported their subjective experiences as positive yet negative bodily feelings were enhanced in the active condition. Notably, participants remained effectively blinded throughout the trials.
Discussion
In conclusion, our findings do not support the idea that microdosing psilocybin reliably enhances cognitive or emotional functioning beyond placebo. Future research should explore individual differences in response to microdosing and examine whether specific populations might benefit from targeted microdosing interventions.
Research Summary of 'Cognitive and Subjective Effects of Psilocybin Microdosing: Results from Two Double-Blind Placebo-Controlled Longitudinal Trials'
Introduction
Earlier anecdotal and observational reports have portrayed psychedelic microdosing as a means to boost focus, creativity and mood, prompting interest in its potential therapeutic use for attentional and affective disorders. However, placebo-controlled evidence has been inconsistent: some open or poorly controlled studies reported improvements in well-being, mindfulness, and convergent thinking, but many effects vanished once expectancy and blinding were modelled. The field is also hampered by small samples, heterogeneous dosing regimens, diverse outcome measures and a lack of a unifying mechanistic framework, leaving it difficult to determine whether microdosing produces reliable cognitive or emotional changes. Prochazkova and colleagues designed two randomized, double-blind, placebo-controlled longitudinal trials to address these gaps by testing whether psilocybin microdosing biases cognitive control toward flexibility at the expense of persistence. Using the Metacontrol State Model (MSM) as the organising theory, the investigators selected a battery of behavioural tasks and questionnaires predicted to detect shifts along the persistence–flexibility axis (e.g., AX-CPT, Multi-Armed Bandit, Reference-Back, Attentional Blink, N-back, RMET) alongside measures of well-being, psychological flexibility and momentary mood. The goal was to evaluate acute and cumulative effects of two microdosing regimens in semi-naturalistic workshop settings while maintaining rigorous placebo control and blinding.
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Study Details
- Study Typeindividual
- Journal
- Compound
- Topics
- APA Citation
Prochazkova, L., Marschall, J., Lippelt, D. P., Schon, N. R., Kuchař, M., & Hommel, B. (2026). Cognitive and Subjective Effects of Psilocybin Microdosing: Results from Two Double-Blind Placebo-Controlled Longitudinal Trials. Neuropharmacology, 283, 110722. https://doi.org/10.1016/j.neuropharm.2025.110722
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