Validation of the Psychological Insight Scale: A new scale to assess psychological insight following a psychedelic experience
The authors developed and validated the six- to seven‑item Psychological Insight Scale (PIS) to assess post‑psychedelic insight, finding a single principal component explaining 73.6% of variance and excellent internal consistency (average Cronbach’s α = 0.94) with supporting criterion and convergent validity. PIS scores significantly mediated the relationship between emotional breakthrough during the experience and long‑term well‑being, suggesting insight is a key mechanism linking acute psychedelic effects to sustained psychological outcomes.
Authors
- Fernando Rosas
- Robin Carhart-Harris
- Christopher Timmermann
Published
Abstract
Introduction
As their name suggests, ‘psychedelic’ (mind-revealing) compounds are thought to catalyse processes of psychological insight; however, few satisfactory scales exist to sample this. This study sought to develop a new scale to measure psychological insight after a psychedelic experience: the Psychological Insight Scale (PIS).
Methods
The PIS is a six- to seven-item questionnaire that enquires about psychological insight after a psychedelic experience (PIS-6) and accompanied behavioural changes (PIS item 7). In total, 886 participants took part in a study in which the PIS and other questionnaires were completed in a prospective fashion in relation to a planned psychedelic experience. For validation purposes, data from 279 participants were analysed from a non-specific ‘global psychedelic survey’ study.
Results
Principal components analysis of PIS scores revealed a principal component explaining 73.57% of the variance, which displayed high internal consistency at multiple timepoints throughout the study (average Cronbach’s α = 0.94). Criterion validity was confirmed using the global psychedelic survey study, and convergent validity was confirmed via the Therapeutic-Realizations Scale. Furthermore, PIS scores significantly mediated the relationship between emotional breakthrough and long-term well-being.
Conclusion
The PIS is complementary to current subjective measures used in psychedelic studies, most of which are completed in relation to the acute experience. Insight – as measured by the PIS – was found to be a key mediator of long-term psychological outcomes following a psychedelic experience. Future research may investigate how insight varies throughout a psychedelic process, its underlying neurobiology and how it impacts behaviour and mental health.
Research Summary of 'Validation of the Psychological Insight Scale: A new scale to assess psychological insight following a psychedelic experience'
Introduction
Research into psychedelic-assisted change has increasingly suggested that the acute subjective features of a psychedelic experience—particularly peak or emotional breakthrough experiences—may mediate enduring psychological benefits. Prior studies have linked self-reported insight during or after psychedelic sessions to reductions in depressive symptoms and to changes in addictive behaviours, and measures such as the Mystical Experience Questionnaire (MEQ), the Emotional Breakthrough Inventory (EBI) and the Challenging Experience Questionnaire (CEQ) have been used to capture related acute phenomena. However, the investigators note a gap: existing insight measures are either trait-focused or designed to capture insight during the acute session rather than insight that crystallises in the days and weeks after an experience (the so-called subacute or ‘‘afterglow’’ period). Peill and colleagues therefore developed the Psychological Insight Scale (PIS), a seven-item instrument with a six-item core (PIS-6) assessing personal psychological insight emerging after an experience and a separate behavioural item (PIS item 7) to capture consequent positive changes in behaviour. The study aimed to validate the PIS psychometrically, testing factor structure and internal reliability, and to establish criterion (predictive and postdictive), concurrent and convergent validity across two prospective online samples: a ceremony/retreat cohort and a broader global psychedelic survey. Key hypotheses were that early post-acute PIS scores would predict improved well-being at 2 weeks, that PIS scores would correlate with contemporaneous well-being, that acute measures (EBI, MEQ, CEQ) would predict later PIS scores, and that PIS would converge with existing insight measures (MIS and SRIS-IN).
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Study Details
- Study Typeindividual
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- APA Citation
Peill, J. M., Trinci, K. E., Kettner, H., Mertens, L. J., Roseman, L., Timmermann, C., Rosas, F. E., Lyons, T., & Carhart-Harris, R. L. (2022). Validation of the Psychological Insight Scale: A new scale to assess psychological insight following a psychedelic experience. Journal of Psychopharmacology, 36(1), 31-45. https://doi.org/10.1177/02698811211066709
References (40)
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Davis, A. K., Streeter Barrett, F., Griffiths, R. R. et al. · Journal of Psychopharmacology (2021)
Davis, A. K., Clifton, J. M., Weaver, E. G. et al. · Journal of Psychopharmacology (2020)
Erritzoe, D., Roseman, L., Nour, M. R. et al. · Acta Psychiatrica Scandinavica (2018)
Garcia-Romeu, A., Davis, A. K., Griffiths, R. R. et al. · Frontiers in Psychiatry (2020)
Garcia-Romeu, A., Davis, A. K., Fire Erowid et al. · Journal of Psychopharmacology (2019)
Kirchner, K. · Journal of Psychopharmacology (2014)
Griffiths, R. R. · Journal of Psychopharmacology (2008)
Griffiths, R. R., Richards, W. A., Mccann, U. et al. · Journal of Psychopharmacology (2006)
Haijen, E. C. H. M., Kaelen, M., Roseman, L. et al. · Frontiers in Pharmacology (2018)
Hübner, S., Haijen, E. C. H. M., Kaelen, M. et al. · Journal of Medical Internet Research (2021)
Johnson, M. W., Richards, W. A., Griffiths, R. R. · Journal of Psychopharmacology (2008)
Johnstad, P. G. · Journal of Psychedelic Studies (2021)
Lyons, T., Carhart-Harris, R. L. · Frontiers in Psychology (2018)
Maclean, K. A., Johnson, M. W., Griffiths, R. R. · Journal of Psychopharmacology (2011)
MacLean, K. A., Leoutsakos, J. S., Johnson, M. W. et al. · Journal for the Scientific Study of Religion (2012)
Moreno, F. A., Wiegand, C. B., Taitano, E. K. et al. · Journal of Clinical Psychiatry (2006)
Noorani, T., Garcia-Romeu, A., Swift, T. C. et al. · Journal of Psychopharmacology (2018)
Nutt, D. J., Erritzoe, D., Carhart-Harris, R. L. · Cell (2020)
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Roseman, L., Nutt, D. J., Carhart-Harris, R. L. · Frontiers in Pharmacology (2018)
Ross, S., Bossis, A. P., Guss, J. et al. · Journal of Psychopharmacology (2016)
Studerus, E., Gamma, A., Vollenweider, F. X. · PLOS ONE (2010)
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Watts, R., Day, C. M., Krzanowski, J. et al. · Journal of Humanistic Psychology (2017)
Wilcox, C. E. · Journal of Psychoactive Drugs (2014)
Williams, T. M., Davis, A. K., Xin, Y. et al. · Drugs Education Prevention and Policy (2020)
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