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Roland R. Griffiths

Johns Hopkins University, Johns Hopkins Medicine

100 papers in the library · 21,304 citations · publishing 1986-2025

Papers

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Effects of Psilocybin on Religious and Spiritual Attitudes and Behaviors in Clergy from Various Major World Religions

Psychedelic Medicine May 16, 2025 Roland R. Griffiths, William A. Richards, Robert L. Jesse et al. 14 citations

Background: Although historical writings, anthropological accounts, and experimental studies document associations between psilocybin use and religion, no prospective experimental study has investigated how the effects of psilocybin are experienced and interpreted by religious clergy. This exploratory study evaluated the overall safety and the acute and enduring effects of psilocybin in clergy....

Sex Differences in Religious Beliefs Before and After an Entity Encounter During an Ayahuasca Experience.

Journal of Psychoactive Drugs February 13, 2025 Yitong Xin, Roland R. Griffiths, Alan K. Davis 1 citation

An interesting aspect of entity encounters during psychedelic experiences is their ability to transform one's religious beliefs. However, little is known about sex differences in these transformations. This study investigates sex differences in changes in religious beliefs before and after an entity encounter among ayahuasca users. Data were collected via an anonymous Internet-based survey (N =...

A Field-Wide Review and Analysis of Study Materials Used in Psilocybin Trials: Assessment of Two Decades of Research

Psychedelic Medicine January 20, 2025 Marianna Graziosi, Gabrielle Agin-Liebes, Mary P Cosimano et al. 9 citations

Introduction: Serotonergic psychedelics, serotonin 2A receptor agonists such as psilocybin that can result in substantially altered states of consciousness, are used in recreational and research settings. The safety of psychedelic experiences in research settings is supported by controlled physical environments, presence of clinical and medical staff to address emergent issues, screening for...

Psilocybin-assisted psychotherapy improves psychiatric symptoms across multiple dimensions in patients with cancer

Nature Mental Health October 7, 2024 Petros Petridis, Jack Grinband, Gabrielle Agin-Liebes et al. 10 citations

Psilocybin-assisted psychotherapy (PAP) has shown promise in treating mood and anxiety disorders in patients with cancer. However, patients with cancer often suffer from more than just depression and anxiety, and so far, PAP's effect on other psychiatric symptoms remains largely unknown. To address this gap, we pooled previously unpublished data from two phase II, randomized, placebo-controlled...

Belief change and agnostic frames in psychedelic research and clinical contexts

Philosophical Perspectives on Psychedelic Psychiatry September 13, 2024 David B. Yaden, Sandeep M. Nayak, Roland R. Griffiths 4 citations

Abstract The proportion of people who change their metaphysical beliefs after psychedelic experiences is not yet known with specificity. However, it appears that belief changes can occur in some cases, and evidence more precisely estimating the prevalence and magnitude of such belief changes is accruing. The evidence for metaphysical belief changes is reviewed and the potential psychological...

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

Journal of Psychoactive Drugs May 7, 2024 Sandeep M. Nayak, Sydney H White, Samantha Hilbert et al. 18 citations

Recent studies suggest psychedelic use may be associated with changes in a variety of beliefs or belief-like states, including increased 1) mind perception, 2) non-naturalistic beliefs, and 3) Atheist-Believer status (e.g. believer, agnostic, or nonbeliever). We conducted a prospective longitudinal study among participants (N = 657) who planned to have a psilocybin experience outside a...

The therapeutic alliance between study participants and intervention facilitators is associated with acute effects and clinical outcomes in a psilocybin-assisted therapy trial for major depressive disorder

PLoS One March 14, 2024 Adam W. Levin, Rafaelle Lancelotta, Nathan D. Sepeda et al. 65 citations

We examined if the therapeutic alliance between study participants and intervention facilitators in a psilocybin-assisted therapy (PAT) trial changed over time and whether there were relationships between alliance, acute psilocybin experiences, and depression outcomes. In a randomized, waiting list-controlled clinical trial for major depressive disorder in adults ( N = 24), participants were...

Unique effects of sedatives, dissociatives, psychedelics, stimulants, and cannabinoids on episodic memory: A review and reanalysis of acute drug effects on recollection, familiarity, and metamemory.

Psychological review March 1, 2024 Manoj K. Doss, Jason Samaha, Frederick S. Barrett et al. 24 citations

Despite distinct classes of psychoactive drugs producing putatively unique states of consciousness, there is surprising overlap in terms of their effects on episodic memory and cognition more generally. Episodic memory is supported by multiple subprocesses that have been mostly overlooked in psychopharmacology and could differentiate drug classes. Here, we reanalyzed episodic memory confidence...

Impact of Psilocybin on Peripheral Cytokine Production

Psychedelic Medicine February 28, 2024 Dana D. DiRenzo, Jamie Perin, Erika Darrah et al. 4 citations

This preliminary study suggests that a transient increase in cytokine production ≤1-week postpsilocybin may be found, although not consistently across patient populations. More broadly, peripheral cytokine production is possibly altered by psilocybin administration. ClinicalTrials.gov Identifier: NCT01988311.

Naturalistic psilocybin use is associated with persisting improvements in mental health and wellbeing: results from a prospective, longitudinal survey

Frontiers in Psychiatry September 19, 2023 Hillary Jackson, Sara So, Abigail Yaffe et al. 87 citations

Introduction The classic psychedelic psilocybin, found in some mushroom species, has received renewed interest in clinical research, showing potential mental health benefits in preliminary trials. Naturalistic use of psilocybin outside of research settings has increased in recent years, though data on the public health impact of such use remain limited. Methods This prospective, longitudinal...

Single-Dose Psilocybin Treatment for Major Depressive Disorder

JAMA August 31, 2023 Charles L. Raison, Gerard Sanacora, Joshua Woolley et al. 493 citations

Importance Psilocybin shows promise as a treatment for major depressive disorder (MDD). Objective To evaluate the magnitude, timing, and durability of antidepressant effects and safety of a single dose of psilocybin in patients with MDD. Design, Setting, and Participants In this phase 2 trial conducted between December 2019 and June 2022 at 11 research sites in the US, participants were...

Double-Blind Comparison of the Two Hallucinogens Dextromethorphan and Psilocybin: Experience-Dependent and Enduring Psychological Effects in Healthy Volunteers

Psychedelic Medicine August 30, 2023 Samantha Hilbert, David S. Mathai, Nathan D. Sepeda et al. 10 citations

This analysis suggests the utility of exploring clinical applications of dissociatives that occur within the supportive contexts that are characteristic of psychedelic research and that prioritize the optimization of psychologically valuable drug experiences. This study was registered with ClinicalTrials.gov (NCT02033707).

Assessing the risk of symptom worsening in psilocybin-assisted therapy for depression: A systematic review and individual participant data meta-analysis

Psychiatry Research July 23, 2023 Otto Simonsson, Per Carlbring, Robin Carhart-Harris et al. 24 citations

We conducted a meta-analysis using individual participant data from three, two-dose psilocybin trials for depression (N = 102) with the aim of assessing the risk of symptom worsening. Clinically significant symptom worsening occurred for a minority of participants in the psilocybin and escitalopram conditions (∼10%) and for a majority of participants in the waitlist condition (63.6%). Using...

Translation and Initial Psychometric Evaluation of Spanish Versions of Three Psychedelic Acute Effects Measures: Mystical, Challenging, and Insight Experiences

Journal of Psychoactive Drugs July 14, 2023 Christopher Timmermann, Aki Nikolaidis, Alan K. Davis et al. 4 citations

This study translated and tested the psychometric properties of acute psychedelic effects measures among Spanish-speaking people. The Psychological Insight Questionnaire (PIQ), Challenging Experiences Questionnaire (CEQ), and Mystical Experiences Questionnaire (MEQ) were translated before being incorporated into a web-based survey. We recruited native Spanish-speakers (N = 442; Mage = 30.8, SD...

Naturalistic Psilocybin Use Increases Mind Perception but not Atheist-Believer status: A Prospective Longitudinal Study

June 9, 2023 Sandeep M. Nayak, Sydney H White, Samantha Hilbert et al. 1 citation preprint

Recent studies suggest psychedelic use may be associated with changes in a variety of beliefs or belief-like states, including increased 1) mind perception, 2) non-naturalistic beliefs, and 3) Atheist-Believer status (e.g., believer, agnostic, or non-believer). We conducted a prospective longitudinal study among participants (N = 657) who planned to have a psychedelic experience. We asked...

Attenuation of psilocybin mushroom effects during and after SSRI/SNRI antidepressant use

Journal of Psychopharmacology June 8, 2023 Natalie Gukasyan, Roland R. Griffiths, David B. Yaden et al. 60 citations

Background: Psilocybin is being studied for depression, but little is known about how it interacts with common antidepressants. Limited data suggest that psilocybin’s effects may be diminished by serotonergic antidepressants acutely and even after a medication washout period. Aims: To learn the extent to which antidepressants may diminish the effects of psilocybin-containing mushrooms both...

Corrigendum to 'Psilocybin induces spatially constrained alterations in thalamic functional organizaton and connectivity': Neuroimage 2022 Oct 15;260:119434.

Neuroimage May 4, 2023 Andrew Gaddis, Daniel E. Lidstone, Mary Beth Nebel et al. correction

Corrigendum to 'Psilocybin induces spatially constrained alterations in thalamic functional organizaton and connectivity': Neuroimage 2022 Oct 15;260:119434.

Belief changes associated with psychedelic use.

Journal of psychopharmacology (Oxford, England) 2023 Sandeep M. Nayak, Manvir Singh, David B. Yaden et al. 87 citations

Psychedelic use is anecdotally associated with belief changes, although few studies have tested these claims. Characterize a broad range of psychedelic occasioned belief changes. A survey was conducted in 2374 respondents who endorsed having had a belief changing psychedelic experience. Participants rated their agreement with belief statements Before and After the psychedelic experience as well...

Clinical Trial Design Challenges and Opportunities for Emerging Treatments for Opioid Use Disorder: A Review.

JAMA Psychiatry 2023 Brian D Kiluk, Bethea A Kleykamp, Sandra D Comer et al. 22 citations

Novel treatments for opioid use disorder (OUD) are needed to address both the ongoing opioid epidemic and long-standing barriers to existing OUD treatments that target the endogenous μ-opioid receptor (MOR) system. The goal of this review is to highlight unique clinical trial design considerations for the study of emerging treatments for OUD that address targets beyond the MOR system. In...

Psychedelic Science, Contemplative Practices, and Indigenous and Other Traditional Knowledge Systems: Towards Integrative Community-Based Approaches in Global Health.

Journal of Psychoactive Drugs 2023 Julian Urrutia, Brian T Anderson, Sean J Belouin et al. 21 citations

As individuals and communities around the world confront mounting physical, psychological, and social threats, three complimentary mind-body-spirit pathways toward health, wellbeing, and human flourishing remain underappreciated within conventional practice among the biomedical, public health, and policy communities. This paper reviews literature on psychedelic science, contemplative practices,...

Subtypes of the psychedelic experience have reproducible and predictable effects on depression and anxiety symptoms.

J Affect Disord December 27, 2022 Aki Nikolaidis, Rafaelle Lancelotta, Natalie Gukasyan et al. 24 citations

BackgroundSubjective experiences seem to play an important role in the enduring effects of psychedelic experiences. Although the importance of the subjective experience on the impact of psychedelics is frequently discussed, a more detailed understanding of the subtypes of psychedelic experiences and their associated impacts on mental health has not been well documented.MethodsIn the current...

Psychedelic-Assisted Therapy for People with Eating Disorders.

Current Psychiatry Reports December 1, 2022 Natalie Gukasyan, Colleen C Schreyer, Roland R. Griffiths et al. 29 citations

A growing body of research suggests psychedelic-assisted therapy (PAT) may be safe and effective for a variety of mental health conditions. Among these, eating disorders have been a recent target of interest. This review provides an up-to-date summary of the potential mechanisms and use of PAT in people diagnosed with eating disorders, with a focus on anorexia nervosa. Classic psychedelics may...

Serotonergic antidepressant use is associated with weaker psilocybin effects

October 28, 2022 Natalie Gukasyan, Roland R. Griffiths, David B. Yaden et al. 1 citation preprint

Background: Psilocybin is being studied for depression, but little is known about how it interacts with common antidepressants. Limited data suggests that psilocybin’s effects may be diminished by serotonergic antidepressants acutely and even after a medication washout period.Aims: To learn the extent to which serotonergic antidepressants may diminish psilocybin’s effects both concurrently and...

Psilocybin induces spatially constrained alterations in thalamic functional organizaton and connectivity.

Neuroimage October 15, 2022 Andrew Gaddis, Daniel E. Lidstone, Mary Beth Nebel et al. 38 citations

Classic psychedelics, such as psilocybin and LSD, and other serotonin 2A receptor (5-HT2AR) agonists evoke acute alterations in perception and cognition. Altered thalamocortical connectivity has been hypothesized to underlie these effects, which is supported by some functional MRI (fMRI) studies. These studies have treated the thalamus as a unitary structure, despite known differential 5-HT2AR...