Major Depressive Disorder (MDD)Depressive Disorders

Psychedelics alter metaphysical beliefs

Using large prospective online samples and an independent controlled trial, the authors show that psychedelic use shifts metaphysical beliefs away from physicalist/materialist views and towards panpsychism and fatalism, with changes detectable up to six months. These shifts correlated with greater past use and improved mental-health outcomes, were moderated by baseline impressionability and mediated by perceived emotional synchrony during the experience, implying a causal influence of psychedelics on metaphysical belief.

Authors

  • Fernando Rosas
  • Robin Carhart-Harris
  • Christopher Timmermann

Published

Scientific Reports
individual Study

Abstract

Are psychedelics able to induce lasting changes in metaphysical beliefs? While it is popularly believed that they can, this has never been systematically tested. Here we exploited a large sample derived from prospective online surveying to determine whether and how beliefs concerning the nature of reality, consciousness, and free-will, change after psychedelic use. Results revealed significant shifts away from ‘physicalist’ or ‘materialist’ views, and towards panpsychism and fatalism, post use. These changes remained detectable at 6 months, and were associated with the extent of past use and improved mental-health outcomes. Path modelling suggested that the belief-shifts were moderated by impressionability at baseline and mediated by perceived emotional synchrony with others during the psychedelic experience. The observed belief-shifts post psychedelic use were confirmed by data from an independent controlled clinical trial. Together, these findings imply that psychedelic use has a causal influence on metaphysical beliefs – shifting them away from ‘hard materialism’.

Available with Blossom Pro

Research Summary of 'Psychedelics alter metaphysical beliefs'

Introduction

Metaphysics concerns fundamental questions about reality, consciousness and free will, and people typically hold distinct metaphysical positions even if not explicitly aware of them. Timmermann and colleagues note that intense life events and altered states — including psychedelic experiences — can make such beliefs explicit, and that psychedelic experiences often include features (mystical-type experiences, perceived encounters with supernatural entities, feelings of unity or cosmic consciousness) that could plausibly induce durable shifts in metaphysical outlooks. Prior evidence for such shifts has been largely anecdotal, qualitative or retrospective, and no systematic, controlled quantitative study had tested whether psychedelics alter metaphysical beliefs. This study set out to address three linked questions: whether psychedelic use can causally affect core metaphysical beliefs about reality, consciousness and free will; whether any belief changes relate to mental-health outcomes; and what psychological mechanisms underlie the putative changes. To do so, the researchers conducted a prospective survey of people planning to attend psychedelic ceremonial retreats, measuring beliefs before and after use, and sought external validation by analysing data from an independent double-blind randomised clinical trial comparing psilocybin therapy with a 6-week course of escitalopram in patients with major depressive disorder.

Expert Research Summaries

Go Pro to access AI-powered section-by-section summaries, editorial takes, and the full research toolkit.

See Pro PlansAlready have an account? Sign in

Full Text PDF

Full Paper PDF

Pro members can view the original manuscript directly in the browser.

See Pro PlansAlready have an account? Sign in
Open PDF in new tab

Study Details

References (28)

Papers cited by this study that are also in Blossom

Pivotal Mental States

Brouwer, A., Carhart-Harris, R. L. · Journal of Psychopharmacology (2020)

Validation of the revised Mystical Experience Questionnaire in experimental sessions with psilocybin

Barrett, F. S., Johnson, M. W., Griffiths, R. R. · Journal of Psychopharmacology (2015)

Survey of entity encounter experiences occasioned by inhaled N,N-dimethyltryptamine: Phenomenology, interpretation, and enduring effects

Davis, A. K., Clifton, J. M., Weaver, E. G. et al. · Journal of Psychopharmacology (2020)

Mystical-type experiences occasioned by psilocybin mediate the attribution of personal meaning and spiritual significance 14 months later

Griffiths, R. R. · Journal of Psychopharmacology (2008)

Psilocybin-induced spiritual experiences and insightfulness are associated with synchronization of neuronal oscillations

Kometer, M., Pokorny, T., Seifritz, E. et al. · Psychopharmacology (2015)

Survey of subjective “God encounter experiences”: Comparisons among naturally occurring experiences and those occasioned by the classic psychedelics psilocybin, LSD, ayahuasca, or DMT

Griffiths, R. R., Hurwitz, E. S., Davis, A. K. et al. · PLOS ONE (2019)

171 cited
Rapid and sustained symptom reduction following psilocybin treatment for anxiety and depression in patients with life-threatening cancer: A randomized controlled trial

Ross, S., Bossis, A. P., Guss, J. et al. · Journal of Psychopharmacology (2016)

Transformative experience and social connectedness mediate the mood-enhancing effects of psychedelic use in naturalistic settings

Forstmann, M., Yudkin, D. A., Prosser, A. M. B. et al. · PNAS (2020)

The peak experience variable in DPT-assisted psychotherapy with cancer patients

Richards, W. A., Rhead, J. C., Dileo, F. B. et al. · Journal of Psychedelic Drugs (2012)

LSD enhances suggestibility in healthy volunteers

Carhart-Harris, R. L., Kaelen, M., Whalley, M. G. et al. · Psychopharmacology (2014)

257 cited
Show all 28 references
Positive expectations predict improved mental-health outcomes linked to psychedelic microdosing

Kaertner, L. S., Steinborn, M. B., Kettner, H. et al. · Scientific Reports (2021)

112 cited
Effects of psilocybin therapy on personality structure

Erritzoe, D., Roseman, L., Nour, M. R. et al. · Acta Psychiatrica Scandinavica (2018)

219 cited
Mystical experiences occasioned by the hallucinogen psilocybin lead to increases in the personality domain of openness

Maclean, K. A., Johnson, M. W., Griffiths, R. R. · Journal of Psychopharmacology (2011)

The therapeutic potential of psychedelic drugs: past, present, and future

Carhart-Harris, R. L., Goodwin, G. M. · Neuropsychopharmacology (2017)

Lifetime experience with (classic) psychedelics predicts pro-environmental behavior through an increase in nature relatedness

Forstmann, M., Sagioglou, C. · Journal of Psychopharmacology (2017)

134 cited
Increased nature relatedness and decreased authoritarian political views after psilocybin for treatment-resistant depression

Lyons, T., Carhart-Harris, R. L. · Journal of Psychopharmacology (2018)

Psychedelics and the essential importance of context

Carhart-Harris, R. L., Roseman, L., Haijen, E. C. H. M. et al. · Journal of Psychopharmacology (2018)

Psychedelics promote structural and functional neural plasticity

Ly, C., Greb, A. C., Cameron, L. P. et al. · Cell Reports (2018)

REBUS and the Anarchic Brain: Toward a Unified Model of the Brain Action of Psychedelics

Carhart-Harris, R. L., Friston, K. J. · Pharmacological Reviews (2019)

Set and setting, psychedelics and the placebo response: An extra-pharmacological perspective on psychopharmacology

Hartogsohn, I. · Journal of Psychopharmacology (2016)

Psychedelic Communitas: Intersubjective experience during psychedelic group sessions predicts enduring changes in psychological wellbeing and social connectedness

Kettner, H., Rosas, F. E., Timmermann, C. et al. · Frontiers in Pharmacology (2021)

157 cited
Trial of Psilocybin versus Escitalopram for Depression

Carhart-Harris, R. L., Giribaldi, B., Watts, R. et al. · New England Journal of Medicine (2021)

927 cited
Patients’ accounts of increased “Connectedness” and “Acceptance” after psilocybin for treatment-resistant depression

Watts, R., Day, C. M., Krzanowski, J. et al. · Journal of Humanistic Psychology (2017)

LSD-assisted psychotherapy for anxiety associated with a life-threatening disease: a qualitative study of acute and sustained subjective effects

Kirchner, K. · Journal of Psychopharmacology (2014)

389 cited
DMT models the near-death experience

Timmermann, C., Roseman, L., Williams, L. et al. · Frontiers in Psychology (2018)

A qualitative report on the subjective experience of intravenous psilocybin administered in an FMRI environment

Nutt, D. J., Carhart-Harris, R. L. · Current Drug Abuse Reviews (2015)

50 cited
Prediction of psilocybin response in healthy volunteers

Studerus, E., Gamma, A., Kometer, M. et al. · PLOS ONE (2012)

Predicting responses to psychedelics: a prospective study

Haijen, E. C. H. M., Kaelen, M., Roseman, L. et al. · Frontiers in Pharmacology (2018)

339 cited

Cited By (44)

Papers in Blossom that reference this study

Intact neurophysiological markers of death denial in long-term ayahuasca users

Dor-Ziderman, Y., David, J., Berkovich-Ohana, A. · Psychopharmacology (2025)

Prediction of hallucinogen persisting perception disorder and thought disturbance symptoms following psychedelic use

Zhou, K., De Wied, D., Carhart-Harris, R. L. et al. · PNAS (2025)

On Minimizing Risk and Harm in the Use of Psychedelic

Evans, J., Aixalà, M., Anderson, B. T. et al. · Psychiatric Research & Clinical Practice (2025)

An Integrated theory of false insights and beliefs under psychedelics

McGovern, H., Grimmer, H. J., Doss, M. K. et al. · Communications Psychology (2024)

How Do Psychedelics Reduce Fear of Death?

Letheby, C. · Neuroethics (2024)

11 cited
Investigating the relationship between changes in metaphysical beliefs and death anxiety following a significant psychedelic experience

Moreton, S. G., Barr, N., Giese, K. J. · Death Studies (2024)

Psychedelic Experiences Increase Mind Perception but do not Change Atheist-Believer Status: A Prospective Longitudinal Study

Nayak, S., Jackson, H., Griffiths, R. R. et al. · Journal of Psychoactive Drugs (2024)

Unique Psychological Mechanisms Underlying Psilocybin Therapy Versus Escitalopram Treatment in the Treatment of Major Depressive Disorder

Weiss, B., Leor Roseman, •., Giribaldi, B. et al. · International Journal of Mental Health and Addiction (2024)

What Predicts Beneficial Outcomes in Psychedelic Use? A Quantitative Content Analysis of Psychedelic Health Outcomes

Acevedo, E. C., Uhler, S., White, K. et al. · Journal of Psychoactive Drugs (2024)

Exploring mechanisms of psychedelic action using neuroimaging

Erritzoe, D., Timmermann, C., Godfrey, K. et al. · Nature Mental Health (2024)

28 cited
Show all 44 papers
Psychedelics and sexual functioning: a mixed-methods study

Barba, T., Kettne, H., Radu, C. et al. · Scientific Reports (2024)

19 cited
Synthetic surprise as the foundation of the psychedelic experience

De Filippo, R., Schmitz, D. · Neuroscience and Biobehavioral Reviews (2024)

Spiritual health practitioners’ contributions to psychedelic assisted therapy: A qualitative analysis

Peacock, C., Mascaro, J. S., Brauer, E. et al. · PLOS ONE (2024)

21 cited
Navigating Groundlessness: An interview study on dealing with ontological shock and existential distress following psychedelic experiences

Argyri, E. K., Evans, J., Luke, D. et al. · SSRN (2024)

Ayahuasca-induced personal death experiences: prevalence, characteristics, and impact on attitudes toward death, life, and the environment

David, J., Bouso, J. C., Kohek, M. et al. · Frontiers in Psychiatry (2023)

Perceptions of psychedelic personality change, determinants of use, setting and drug moderation: Toward a holistic model

Weiss, B., Sleep, C., Beller, N. et al. · Journal of Psychedelic Studies (2023)

10 cited
Psychological and physiological effects of extended DMT

Luan, L. X., Eckernäs, E., Ashton, M. et al. · Journal of Psychopharmacology (2023)

Alternative beliefs in psychedelic drug users

Lebedev, A. V., Acar, K., Horntvedt, O. et al. · Scientific Reports (2023)

History repeating: guidelines to address common problems in psychedelic science

Van Elk, M., Fried, E. I. · Therapeutic Advances in Psychopharmacology (2023)

94 cited
N, N-Dimethyltryptamine (DMT)-Occasioned Familiarity and the Sense of Familiarity Questionnaire (SOF-Q)

Lawrence, D. W., Timmermann, C. · Journal of Psychoactive Drugs (2023)

Transpersonal Ecodelia: Surveying Psychedelically Induced Biophilia

Luke, D., Gandy, S., Irvine, A. et al. · Psychoactives (2023)

17 cited
On the need for metaphysics in psychedelic therapy and research

Sjöstedt-Hughes, P. · Frontiers in Psychology (2023)

An encounter with the self: A thematic and content analysis of the DMT experience from a naturalistic field study

Michael, P., Luke, D., Robinson, O. · Frontiers in Psychology (2023)

Human brain effects of DMT assessed via EEG-fMRI

Timmermann, C., Roseman, L., Haridas, S. et al. · PNAS (2023)

158 cited
Canalization and plasticity in psychopathology

Carhart-Harris, R. L., Chandaria, S., Erritzoe, D. E. et al. · Neuropharmacology (2023)

A neurophenomenological approach to non-ordinary states of consciousness: hypnosis, meditation, and psychedelics

Timmermann, C., Vollenweider, F. X. · Trends in Cognitive Sciences (2023)

Psychedelic integration challenges: Participant experiences after a psilocybin truffle retreat in the Netherlands

Lutkajtis, A., Evans, J. · Journal of Psychedelic Studies (2023)

The association between naturalistic use of psychedelics and co-occurring substance use disorders

Rabinowitz, J., Lev-Ran, S., Gross, R. · Frontiers in Psychiatry (2023)

Journeying to Ixtlan: Ethics of Psychedelic Medicine and Research for Alzheimer’s Disease and Related Dementias

Peterson, A., Largent, E. A., Sisti, D. et al. · AJOB Neuroscience (2022)

More than meets the eye: The role of sensory dimensions in psychedelic brain dynamics, experience, and therapeutics

Aqil, M., Roseman, L. · Neuropharmacology (2022)

A long trip into the universe: Psychedelics and space travel

Lerer, L. B., Varia, J. · Frontiers in Space Travel (2022)

2 cited
Adverse events in clinical treatments with serotonergic psychedelics and MDMA: A mixed-methods systematic review

Breeksema, J. J., Kuin, B. W., Kamphuis, J. et al. · Journal of Psychopharmacology (2022)

The Watts Connectedness Scale: a new scale for measuring a sense of connectedness to self, others, and world

Watts, R., Kettner, H., Gandy, S. et al. · Psychopharmacology (2022)

Reduced death anxiety and obsessive beliefs as mediators of the therapeutic effects of psychedelics on obsessive compulsive disorder symptomology

Moreton, S. G., Burden-Hill, A., Menzies, R. E. · Clinical Psychologist (2022)

Pharmacological, Neural, and Psychological Mechanisms underlying Psychedelics: A Critical Review

van Elk, M., Yaden, D. B. · Neuroscience and Biobehavioral Reviews (2022)

Pattern Breaking: A Complex Systems Approach to Psychedelic Medicine

Hipólito, I., Mago, J., Rosas, F. E. et al. · Psyarxiv (2022)

Belief changes associated with psychedelic use

Nayak, S., Singh, M., Yaden, D. B. et al. · Journal of Psychopharmacology (2022)

Psychedelics and Psychotherapy: Cognitive-Behavioral Approaches as Default

Yaden, D. B., Earp, D., Graziosi, M. et al. · Frontiers in Psychology (2022)

The Psychedelic Integration Scales: Tools for Measuring Psychedelic Integration Behaviors and Experiences

Whitney, S., Yaden, D. B., Lipson, J. et al. · Frontiers in Psychology (2022)

Naturalistic use of psychedelics is related to emotional reactivity and self-consciousness: The mediating role of ego-dissolution and mystical experiences

Orłowski, P., Ruban, A., Szczypiński, J. et al. · Journal of Psychopharmacology (2022)

A Single Belief-Changing Psychedelic Experience Is Associated With Increased Attribution of Consciousness to Living and Non-living Entities

Nayak, S., Griffiths, R. R. · Frontiers in Psychology (2022)

37 cited
Towards psychedelic apprenticeship: Developing a gentle touch for the mediation and validation of psychedelic-induced insights and revelations

Timmermann, C., Watts, R., Dupuis, D. · Transcultural Psychiatry (2022)

95 cited
Great Expectations: Recommendations for improving the methodological rigor of psychedelic clinical trials

Aday, J. S., Heifets, B. D., Pratscher, S. D. et al. · Psychopharmacology (2021)

Psychedelics as Tools for Belief Transmission. Set, Setting, Suggestibility, and Persuasion in the Ritual Use of Hallucinogens

Dupuis, D. · Frontiers in Psychology (2021)

Your Personal Research Library

Go Pro to save papers, add notes, rate studies, and organize your research into custom shelves.

See Pro PlansSign in