Prediction of Psilocybin Response in Healthy Volunteers
Erich Studerus, Alex Gamma, Michael Kometer, Franz X. Vollenweider
PLoS ONE February 17, 2012 DOI: 10.1371/journal.pone.0030800 via OpenAlex
Summary
AI-generated from the abstractDose is the strongest predictor of how people respond to psilocybin, but non-pharmacological factors also matter. Among 409 administrations to 261 healthy volunteers, pleasant and mystical-type experiences were most strongly associated with high Absorption personality trait, emotional excitement and activity just before the drug, and few recent psychological problems. Unpleasant or anxious reactions were most strongly predicted by high Emotional Excitability, younger age, and undergoing a PET scan during the session. The findings confirm that personality, mood, and setting significantly shape psilocybin's effects, though dose remains the dominant factor.
Study at a glance
| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 409 |
| Population | Healthy volunteers |
| Intervention | Psilocybin |
| Topics | Psilocybin |
| Keywords | Hallucinogen Mood Personality Clinical psychology |
| Citations | 372 |
| Key finding | Drug dose was the most important predictor of acute psilocybin response, but non-pharmacological variables such as Absorption personality trait, pre-drug emotional state, and recent psychological problems also significantly influenced the nature of the experience. |
Abstract
Responses to hallucinogenic drugs, such as psilocybin, are believed to be critically dependent on the user's personality, current mood state, drug pre-experiences, expectancies, and social and environmental variables. However, little is known about the order of importance of these variables and their effect sizes in comparison to drug dose. Hence, this study investigated the effects of 24 predictor variables, including age, sex, education, personality traits, drug pre-experience, mental state before drug intake, experimental setting, and drug dose on the acute response to psilocybin. The analysis was based on the pooled data of 23 controlled experimental studies involving 409 psilocybin administrations to 261 healthy volunteers. Multiple linear mixed effects models were fitted for each of 15 response variables. Although drug dose was clearly the most important predictor for all measured response variables, several non-pharmacological variables significantly contributed to the effects of psilocybin. Specifically, having a high score in the personality trait of Absorption, being in an emotionally excitable and active state immediately before drug intake, and having experienced few psychological problems in past weeks were most strongly associated with pleasant and mystical-type experiences, whereas high Emotional Excitability, low age, and an experimental setting involving positron emission tomography most strongly predicted unpleasant and/or anxious reactions to psilocybin. The results confirm that non-pharmacological variables play an important role in the effects of psilocybin.