Positive expectations predict improved mental-health outcomes linked to psychedelic microdosing
Scientific Reports – January 21, 2021
Source: OpenAlex
Summary
After four weeks, 81 individuals microdosing psychedelics reported improved mood, reduced anxiety, and enhanced mental health, reaching a key clinical endpoint. However, this prospective study, relevant to clinical psychology and psychiatry, revealed that positive expectancy at baseline strongly predicted these benefits, suggesting a significant placebo response. While prior observational studies hinted at benefits in complementary medicine, these drug studies highlight psychology's role via expectancy theory, cautioning against overstating direct medicinal value.
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.