Pahnke’s ‘Good Friday Experiment’: a long-term follow-up and methodological critique
This methodological critique and long-term, between-subjects, follow-up study (n=16) challenges how the mystical experiences occasioned by psilocybin were measured during Walter Pahnke's infamous 'Good Friday experiment' (1963) on the basis of its imprecise questionnaire assessment and unsuccessful placebo blinding. However, all psilocybin subjects participating in the long-term follow-up, but none of the controls, still considered their original experience to have had genuinely mystical elements and to have made a uniquely valuable contribution to their spiritual lives even 27 years after.
Authors
- Rick Doblin
Published
Abstract
Introduction
To investigate the potential of psychedelic drugs to facilitate mystical experience, W. Pahnke (1963) administered psilocybin or placebo to 20 White male Protestant divinity students before Good Friday services. The present study critiques the preparation phase of the experiment, Pahnke's questionnaire for measuring mystical experience, and completeness of his reporting.
Methods
Between 1986 and 1989, the present author recorded personal interviews with 16 of the original Ss. All 16 were re-administered the 100-item questionnaire used for 6-mo follow-up in the original experiment. The original experiment found that psilocybin Ss who experienced a mystical experience would, after 6 mo, report a substantial amount of positive, and virtually no negative, persisting changes in attitude and behavior.
Results
The present study further supports these findings.
Research Summary of 'Pahnke’s ‘Good Friday Experiment’: a long-term follow-up and methodological critique'
Introduction
Pahnke's 1962 "Good Friday" experiment administered psilocybin or a placebo to twenty Protestant divinity students during a Marsh Chapel Good Friday service to test whether psychedelics could facilitate mystical experiences. Earlier reports of the study argued that psilocybin recipients reported more elements of a classical mystical experience and greater persisting positive changes than controls, but raw data from the original project were lost and subsequent legal restrictions prevented replication for decades. Doblin conducted a long-term follow-up and methodological critique roughly 24–27 years after the original study. The follow-up aimed to locate the original participants, re-administer Pahnke's six-month questionnaire, conduct tape-recorded interviews, and reassess both the empirical findings and the original study's methods — in particular the adequacy of the blinding, the questionnaire, and reporting of adverse events.
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Study Details
- Study Typeindividual
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- Compound
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- APA Citation
(1991). Pahnke’s ‘Good Friday Experiment’: a long-term follow-up and methodological critique. Journal of Transpersonal Psychology.
References (1)
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