Of Roots and Fruits A Comparison of Psychedelic and Nonpsychedelic Mystical Experiences
In a sample of 739 self‑selected participants, mystical experiences induced by psychedelic substances were rated more intensely mystical and yielded greater reductions in fear of death, increased sense of purpose and enhanced spirituality compared with non‑psychedelic RSMEs. These differences remained significant after controlling for gender, education, socio‑economic status and religious affiliation, supporting the view that psychedelic‑induced RSMEs are genuinely mystical and generally positive in outcome.
Authors
- David Yaden
- Anna Belser
Published
Abstract
Experiences of profound existential or spiritual significance can be triggered reliably through psychopharmacological means using psychedelic substances. However, little is known about the benefits of religious, spiritual, or mystical experiences (RSMEs) prompted by psychedelic substances, as compared with those that occur through other means. In this study, 739 self-selected participants reported the psychological impact of their RSMEs and indicated whether they were induced by a psychedelic substance. Experiences induced by psychedelic substances were rated as more intensely mystical ( d = .75, p < .001), resulted in a reduced fear of death ( d = .21, p < .01), increased sense of purpose ( d = .18, p < .05), and increased spirituality ( d = .28, p < .001) as compared with nonpsychedelically triggered RSMEs. These results remained significant in an expanded model controlling for gender, education, socioeconomic status, and religious affiliation. These findings lend support to the growing consensus that RSMEs induced with psychedelic substances are genuinely mystical and generally positive in outcome.
Research Summary of 'Of Roots and Fruits A Comparison of Psychedelic and Nonpsychedelic Mystical Experiences'
Introduction
Yaden and colleagues frame the study within a longstanding theoretical debate about whether the origins of religious, spiritual, or mystical experiences (RSMEs) matter for their value. Earlier work, notably William James's pragmatism, argues that the worth of such experiences should be judged by their outcomes or "fruits" rather than their physiological or situational causes or "roots." That debate has resurfaced in the context of psychedelic substances, which reliably occasion RSMEs in both laboratory and naturalistic settings; some scholars claim psychedelically induced experiences are essentially the same as spontaneous mystical experiences, while others argue they are qualitatively different or less authentic. This paper sets out to provide empirical data to address that question. Using an online survey, the investigators compared self-reported RSMEs that participants identified as psychedelically induced with those attributed to nonpsychedelic triggers. They hypothesised there would be nonsignificant differences between the two groups on (a) mystical quality, (b) positive impact across domains including family, fear of death, health, and sense of purpose, and (c) religiosity and spirituality, thereby testing whether the "roots" (origin) influence the "fruits" (outcomes) of RSMEs.
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Study Details
- Study Typeindividual
- Journal
- Authors
- APA Citation
Yaden, D. B., Le Nguyen, K. D., Kern, M. L., Belser, A. B., Eichstaedt, J. C., Iwry, J., Smith, M. E., Wintering, N. A., Hood, R. W., & Newberg, A. B. (2017). Of Roots and Fruits A Comparison of Psychedelic and Nonpsychedelic Mystical Experiences. Journal of Humanistic Psychology, 57(4), 338-353. https://doi.org/10.1177/0022167816674625
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Kangaslampi, S. · Journal of Psychedelic Studies (2023)
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Vollenweider, F. X., Smallridge, J. W. · Pharmacopsychiatry (2022)
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Qiu, X., Minda, J. P. · Psyarxiv (2021)
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