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Cognitive and subjective effects of psilocybin microdosing: Results from two double-blind placebo-controlled
Luisa Prochazkova1, Josephine Marschall1, Dominique Patrick Lippelt1
1Institute of Psychology, Leiden University, Wassenaarseweg 52, 2333 AK, Leiden, the Netherlands.
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 a 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.
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