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William A Richards

The Bill Richards Center for Healing, Sunstone Therapies, Rockville, MD, USA.

3 papers in the library · 987 citations · publishing 2011-2026

Papers

Psilocybin occasioned mystical-type experiences: immediate and persisting dose-related effects.

Psychopharmacology December 1, 2011 Roland R Griffiths, Matthew W Johnson, William A Richards et al. 938 citations

Psilocybin can produce mystical-type experiences that lead to lasting positive changes in attitudes, mood, and behavior. In a double-blind study, 18 adults (17 with no prior hallucinogen use) received 0, 5, 10, 20, or 30 mg/70 kg psilocybin in five sessions under supportive conditions. At the two highest doses, 72% of volunteers reported a mystical-type experience, and 39% experienced extreme anxiety or fear. One month later, participants rated these sessions as having substantial personal and spiritual significance, with the ascending dose sequence showing greater positive effects. At 14 months, these positive ratings remained undiminished and were consistent with observer reports. The effects generally increased with dose.

Top Ten Tips Palliative Care Clinicians Should Know About Psychedelic-Assisted Therapy in the Context of Serious Illness.

Journal of palliative medicine August 1, 2022 William E Rosa, Zachary Sager, Megan Miller et al. 49 citations

Psychedelic-assisted therapy (PAT) is a promising treatment for conditions like treatment-resistant depression, substance use disorder, and PTSD. In palliative care, a single PAT session can produce lasting reductions in anxiety, depression, and demoralization—symptoms that harm quality of life for seriously ill and end-of-life patients. Although interest in psychedelics has revived, few resources exist for applying PAT in hospice and palliative care. This article provides 10 evidence-informed tips for palliative care clinicians, developed with international experts, to help familiarize teams with PAT, address legal and logistical barriers, discuss therapeutic competencies, and highlight approaches to maximize safety and benefits for patients and caregivers.

Integrating the Mystical Experience Questionnaire Into a Broader Psychometric Framework: English Validation of the Psychedelic Experience Scale and Comparison of Psilocybin and LSD Sessions Across Two Controlled Settings.

International journal of methods in psychiatric research June 1, 2026 Kurt Stocker, Matthias Hartmann, Frederick S Barrett et al.

The eight-factor structure of the Psychedelic Experience Scale (PES48), which includes the Mystical Experience Questionnaire (MEQ30) and additional factors for paradoxicality, connectedness, visual experience, and distressing experience, is valid for use in English. Analysis of 280 measurements from 145 healthy participants in four placebo-controlled psilocybin studies found that six subscales have high internal consistency, one good, and one acceptable. Both the MEQ30 and MEQ40 models show acceptable to good model fits, with better fits in English than in German. All six MEQ40 scale means were higher in English data, suggesting that the PES48 provides a broader conceptualization of mystical and non-mystical psychedelic experiences, and that setting may influence mystical experience.