Tripping on nothing: placebo psychedelics and contextual factors
This placebo-only study (n=33) found that by creating a highly psychedelic-like setting (including actors), a majority of participants believed they felt some drug effects.
Authors
- Olson, J. A.
- Suissa-Rocheleau, L.
- Lifshitz, M.
Published
Abstract
Rationale
Is it possible to have a psychedelic experience from a placebo alone? Most psychedelic studies find few effects in the placebo control group, yet these effects may have been obscured by the study design, setting, or analysis decisions.
Objective
We examined individual variation in placebo effects in a naturalistic environment resembling a typical psychedelic party.
Methods
Thirty-three students completed a single-arm study ostensibly examining how a psychedelic drug affects creativity. The 4-h study took place in a group setting with music, paintings, coloured lights, and visual projections. Participants consumed a placebo that we described as a drug resembling psilocybin, which is found in psychedelic mushrooms. To boost expectations, confederates subtly acted out the stated effects of the drug and participants were led to believe that there was no placebo control group. The participants later completed the 5-Dimensional Altered States of Consciousness Rating Scale, which measures changes in conscious experience.
Results
There was considerable individual variation in the placebo effects; many participants reported no changes while others showed effects with magnitudes typically associated with moderate or high doses of psilocybin. In addition, the majority (61%) of participants verbally reported some effect of the drug. Several stated that they saw the paintings on the walls “move” or “reshape” themselves, others felt “heavy… as if gravity [had] a stronger hold”, and one had a “come down” before another “wave” hit her.
Conclusion
Understanding how context and expectations promote psychedelic-like effects, even without the drug, will help researchers to isolate drug effects and clinicians to maximise their therapeutic potential.
Research Summary of 'Tripping on nothing: placebo psychedelics and contextual factors'
Introduction
Psychedelic experiences are shaped not only by pharmacology but also by non-pharmacological factors such as mindset, expectations, and environment (the so-called "set and setting"). Olson and colleagues note that although placebo effects occur across many domains, placebo arms in psychedelic research have generally shown few effects, which may reflect laboratory settings, study design choices, or analytic practices that obscure individual responses. The authors draw attention to the phenomenon of "contact highs"—drug-like effects experienced without ingestion, reported in naturalistic groups—and argue that such effects have been little studied despite plausible mechanisms including classical conditioning, social modelling, and emotional contagion. This feasibility study set out to test whether a placebo could produce psychedelic-like subjective experiences when delivered in a naturalistic, party-like context with strong expectation manipulations and social modelling. Specifically, the investigators hypothesised that at least some participants would report alterations in consciousness after ingesting an inert capsule that they were led to believe contained a fast-acting psilocybin analogue, and they emphasised examining individual variation rather than group averages.
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Study Details
- Study Typeindividual
- Journal
- Compound
- Topics
- APA Citation
Olson, J. A., Suissa-Rocheleau, L., Lifshitz, M., Raz, A., & Veissière, S. P. L. (2020). Tripping on nothing: placebo psychedelics and contextual factors. Psychopharmacology, 237(5), 1371-1382. https://doi.org/10.1007/s00213-020-05464-5
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