Dose–response relationships of psilocybin-induced subjective experiences in humans
Journal of Psychopharmacology – March 04, 2021
Source: OpenAlex
Summary
Psilocybin, a potent hallucinogen, significantly intensifies subjective experiences. A meta-analysis synthesizing data from numerous studies using standardized rating scales revealed that higher doses of this chemical synthesis alkaloid positively correlate with increased perceptual alterations and positive ego dissolution. Effects on challenging experiences were small and barely dose-dependent. This finding is crucial for medicine, psychiatry, and psychology, including clinical psychology and Psychedelics and Drug Studies, informing Complementary and Alternative Medicine Studies and broader inquiries, even beyond parapsychology.
Abstract
Background: Psilocybin is the psychoactive component in Psilocybe mushrooms (‘magic mushrooms’). Whether and how the quality of the psilocybin-induced experience might mediate beneficial health outcomes is currently under investigation, for example, in therapeutic applications. However, to date, no meta-analysis has investigated the dose-dependency of subjective experiences across available studies. Aim: Establishing dose–response relationships of the subjective experiences induced by psilocybin in healthy study participants and a comparison of patient groups. Method: We applied a linear meta-regression approach, based on the robust variance estimation framework, to obtain linear dose–response relationship estimates on questionnaire ratings after oral psilocybin administration. Data were obtained from the Altered States Database, which contains data extracted from MEDLINE-listed journal articles that used standardized and validated questionnaires: the Altered States of Consciousness Rating Scale, the Mystical Experience Questionnaire and the Hallucinogen Rating Scale. Results: Psilocybin dose positively correlated with ratings on most factors and scales, mainly those referring to perceptual alterations and positively experienced ego dissolution. Measures referring to challenging experiences exhibited small effects and were barely modulated by dose. Conclusion: Psilocybin intensified almost all characteristics of altered states of consciousness assessed with the given questionnaires. Because subjective experiences are not only determined by dose, but also by individual and environmental factors, the results may only apply to controlled laboratory experiments and not to recreational use. This paper may serve as a general literature citation for the use of psilocybin in experimental and clinical research, to compare expected and observed subjective experiences.