Positive expectations predict improved mental-health outcomes linked to psychedelic microdosing
Laura Kaertner, Michael B. Steinborn, Hannes Kettner, Meg J. Spriggs, Leor Roseman, Tobias Buchborn, Maria Bălăeţ, Christopher Timmermann, David Erritzøe, Robin Carhart-Harris
Scientific Reports January 21, 2021 DOI: 10.1038/s41598-021-81446-7 (opens in new tab) via OpenAlex
Summary
AI-generated from the abstractA prospective study of weekly psychedelic microdosing found that participants reported improved well-being, emotional stability, and reduced anxiety and depressive symptoms over four weeks. However, baseline positive expectancy scores predicted these improvements, suggesting a significant placebo response. The findings caution against overinterpreting the therapeutic value of microdosing.
Study at a glance
| Characteristics | Prospective observational study Placebo-controlled Peer reviewed |
|---|---|
| Sample size | 81 |
| Population | Individuals planning a weekly microdosing regimen |
| Intervention | Psychedelic microdosing |
| Duration | Four-week test period |
| Topics | Anxiety |
| Keywords | Mood Expectancy theory Clinical psychology Mental health |
| Citations | 152 |
| Key finding | Positive expectancy at baseline predicted improvements in well-being, indicating a placebo response rather than a direct drug effect. |
Abstract
Abstract Psychedelic microdosing describes the ingestion of near-threshold perceptible doses of classic psychedelic substances. Anecdotal reports and observational studies suggest that microdosing may promote positive mood and well-being, but recent placebo-controlled studies failed to find compelling evidence for this. The present study collected web-based mental health and related data using a prospective (before, during and after) design. Individuals planning a weekly microdosing regimen completed surveys at strategic timepoints, spanning a core four-week test period. Eighty-one participants completed the primary study endpoint. Results revealed increased self-reported psychological well-being, emotional stability and reductions in state anxiety and depressive symptoms at the four-week primary endpoint, plus increases in psychological resilience, social connectedness, agreeableness, nature relatedness and aspects of psychological flexibility. However, positive expectancy scores at baseline predicted subsequent improvements in well-being, suggestive of a significant placebo response. This study highlights a role for positive expectancy in predicting positive outcomes following psychedelic microdosing and cautions against zealous inferences on its putative therapeutic value.