Examining changes in personality following shamanic ceremonial use of ayahuasca

This open-label study (n=256) found that directly after an ayahuasca retreat, and three months later, the personality of the participants was changed. The strongest finding was for neuroticism, but noted should be that there was no control group.

Abstract

“The present study examines the association between the ceremonial use of ayahuasca—a decoction combining the Banistereopsis caapi vine and N,N-Dimethyltryptamine-containing plants—and changes in personality traits as conceived by the Five-Factor model (FFM). We also examine the degree to which demographic characteristics, baseline personality, and acute post-ayahuasca experiences affect personality change. Participants recruited from three ayahuasca healing and spiritual centers in South and Central America (N = 256) completed self-report measures of personality at three timepoints (Baseline, Post, 3-month Follow-up). Informant-report measures of the FFM were also obtained (N = 110). Linear mixed models were used to examine changes in personality and the moderation of those changes by covariates. The most pronounced change was a reduction in Neuroticism dz_{self-reportT1–T2} =  − 1.00; dz_{self-reportT1–T3} =  − .85; dz_{informant-reportT1–T3} =  − .62), reflected in self- and informant-report data. Moderation of personality change by baseline personality, acute experiences, and purgative experiences was also observed.”

Authors: Brandon Weiss, Joshua D. Miller, Nathan T. Carter & W. Keith Campbell

Notes

This is another paper that describes changes in personality after psychedelics. Although changes were found, one can see from figure one in the paper that, although significant, the changes were not that large. The biggest effects were found on the measure of Neuroticism (lower).

With respect to expectancy effects (also see Uthaug and colleagues also published in March 2021), the authors note the following:

“Two notable patterns of change were observed. First, with respect to Neuroticism, participants endorsing an expectancy of favorable change in Neuroticism, depression, and anxiety exhibited higher baseline Neuroticism, and showed a greater decrease in Neuroticism following ceremony (B = − .35) and at Follow-up (B = − .37), compared to participants with lower expectancies.“

Accounting for expectancy effects, the changes in Neuroticism scores still remained significant.

Summary

The revival of interest in psychedelic medicines has two primary strands: laboratory-based clinical research focusing on therapeutic applications of serotonergic psychedelic compounds, and shamanic medicine using psychedelic compounds.

This study examined the effect of ayahuasca on personality. It found that predisposing factors and experiential factors moderated personality changes, but not demographic characteristics and baseline personality.

Ayahuasca shamanism has a long history of ceremonial use among indigenous peoples of Brazil and the Amazonian basin of South America. Studies of ayahuasca in the ceremonial versus laboratory setting may provide insight into key elements of psychedelic-assisted experience that potentiate positive psychological changes.

Shamanic ceremonies include chanting of prayer, use of adjunct plants, engagement with a shaman, and engagement with personal challenges.

Shipibo shamans believe that the ayahuasca decoction has a spirit that helps remove blockages to health, such as “dirty” or “calcified” energies, and that the shaman’s icaro opens up “portals” that guide positive spirits to extract and remove mahua yoshin from ceremony participants.

The dieta process, outside Western medical and scientific training, involves consuming a plant teacher and focusing on its psychospiritual effects/teachings. It has three functions: purificatory, cultivation of intuition, and bestowing of protection.

Psychedelic research as a window into personality change has shown mixed evidence. Changes in Five-Factor model (FFM) domains have been observed across healthy2,33 – 35 and clinical1 samples, including decreases in Harm Avoidance (i.e., characterized by worry36) and increases in Self-Directedness (i.e., adaptive capacity to achieve chosen goals38).

The empirical inconsistency in these findings and null results within placebo-controlled studies may be due to the fact that most studies use small samples and have low statistical power, and that few studies have corroborated self-reported change with informant-reported change.

Predisposing factors for psychedelic experience include mind-set, setting, personality traits, affective states, age, and experimental setting.

A small literature has examined the effects of non-ordinary psychological states on personality. It has been suggested that mystical-type and intense emotional experiences may potentiate change in FFM Openness2, Neuroticism1, and Extraversion1.

Present study

The present study examined whether personality changed following ceremonial use of ayahuasca in a sample of 256 participants using self- and informant-report measures of personality across three timepoints.

We investigated factors that may affect the degree of personality change found in relation to psychedelic experience, and hypothesized that mystical-type experience would contribute to a larger difference in FFM Openness between timepoints.

Examining personality change, main effects of timepoint were observed on Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness. Within a week following ayahuasca ceremony, Neuroticism, Openness, Agreeableness, and Conscientiousness were significantly lower, and Extraversion, .23, .28, .57, .30, and .38, respectively, were significantly higher. Three months following ayahuasca ceremony, Neuroticism was significantly lower, and Extraversion, Openness, Agreeableness, and Conscientiousness were significantly higher than immediately following ayahuasca ceremony. In addition, Conscientiousness was significantly lower three months following ayahuasca ceremony compared to immediately following ayahuasca ceremony.

To examine the degree to which predisposing and experiential factors moderated ayahuasca-induced personality change, linear mixed models were conducted with five sets of moderators. The results show that validity variables, participant characteristics, baseline personality scores, acute experience elements, and ceremony variables moderated personality change.

Results

Two notable patterns of change were observed with respect to Neuroticism, Extraversion, and Conscientiousness: higher baseline Neuroticism and greater decrease in Neuroticism following ceremony and at Follow-up.

Participants with lower expectancies, lower baseline personality, and higher suggestibility showed a greater decrease in Neuroticism following ayahuasca ceremony and at Follow-up.

We examined self-reported change in personality among participants who denied expectancy of favorable change and who exhibited low trait suggestibility. We found that change in Neuroticism and Extraversion was evident, but Conscientiousness was not.

Results indicated that all baseline domain scores were significantly associated with adaptive changes in their respective personality domain three months following ayahuasca ceremony. Participants showed a significant decrease in Neuroticism regardless of their standing on baseline Neuroticism, and participants higher in Extraversion, Agreeableness, and Conscientiousness showed no significant increase in these domains.

With respect to acute experience elements, factor analyses were conducted on (sub)scales of acute experience variables to reduce redundancy. A one-standard-deviation increase in Mystical factor significantly amplified decreases in Neuroticism and increases in Extraversion, Openness, Agreeableness, and Conscientiousness following ayahuasca ceremony.

Ayahuasca ceremony moderated change in personality, with higher AEI Reappraisal experiences resulting in lower levels of Neuroticism, and higher AEI Discomfort resulting in higher levels of Extraversion.

Three sets of variables regarding the ceremonies were examined: ceremony characteristics, perceptions of ceremony, and purgative experiences. The results showed that no ceremony characteristics were significantly associated with change in FFM domains, and that participants with higher levels of certain perceptions and purgative experiences showed greater changes.

Discussion

The present study prospectively explored the ceremonial use of ayahuasca as a potential driver of personality change. It used a series of methodological safeguards to reduce placebo, expectancy, and demand effects, and provided resolution on traits that may be more accurately described by observers.

Ayahuasca ceremony was observed to decrease neuroticism substantially, and remain substantially below pre-retreat scores, three months following ceremony. This decline was also reflected in informant-report data.

In a meta-analysis of clinical interventions, a .57 average pre-post effect size decline in self-report neuroticism was observed. The present results are consistent with previous findings for psychedelic-assisted therapy.

Support for hypotheses predicting change in extraversion and openness was not found as robustly, but the sample size may have been limited and a ceiling effect may have limited upward change in openness.

Baseline personality seemed to be a strong moderator of adaptive changes in personality across domains. Specifically, individuals with higher levels of neuroticism and lower levels of extraversion, openness, agreeableness, and conscientiousness demonstrated the most change towards greater adaptivity in trait scores.

Ayahuasca ceremony induces non-ordinary states of consciousness that may influence subsequent outcomes. Mystical-type experiences were associated with larger adaptive changes in all personal- ity domains, and may be a core component of ayahuasca-induced mystical experience.

Ayahuasca ceremony promotes AEI Reappraisal, a construct reflecting introspective reappraisal of difficult life experiences and negative core beliefs. This construct resembles core elements of psychotherapy.

Support for the influence of certain ceremonial and purgative elements in ayahuasca ceremony raises questions about the unique value of a shamanic context for personality change. However, the results are suggestive that most measured shamanic elements are not additive.

Ayahuasca ceremony may contain additional therapeutic components such as shaman, icaro, purgative elements, cognitive reappraisal, sacramental atmosphere, and communal/group context. These components may help individuals vulnerably confront adversity and enact new behavioral patterns of interpersonal relating.

The results suggest that elements of shamanic philosophy may contribute to adaptive outcomes, and that psychospiritual agents may guide adaptive changes.

Limitations

Although the study had several limitations, such as the absence of a placebo-control group and blinding protocols, it showed that participants with higher baseline openness showed positive personality changes after attending a therapeutically designed retreat in a foreign country.

Conclusion

Attending ayahuasca ceremony was associated with a medium-sized decrease in neuroticism, and predisposing and experiential factors that may potentiate personality change were identified. Furthermore, baseline personality, mystical-type experiences, meta-cognitive reappraisal, and certain shamanic elements emerged as predictors of favorable personality change.

Three hundred thirty participants were recruited from three ayahuasca retreat centers across South and Central America. Of these, 320 validly responding participants provided data for at least one timepoint, and seven participants were removed on the basis of inadequate time-commitment and untimely completion.

A sample of 110 participants had informant-report measurement at Baseline and Follow-up. Independent-samples t-test analyses were conducted to test for differences between final sample participants with informant data (N = 104) and final sample participants without informant data (N = 165).

Methods

Retreat centers in the west Amazon basin offer ayahuasca ceremonies, as well as nunu, flower baths, kambo, sapo, and huachuma. Ayahuasca ceremonies are conjectured to contribute most meaningfully to the observed effects.

A 120-item set of the International Personality Item Pool was used to index self-reported personality traits, and a 60-item set of the International Personality Item Pool was used to index informant-reported personality traits. The IPIP-NEO has demonstrated good reliability and construct validity.

Measures

An original scale was developed, consisting of ten dichotomous items measuring expected change in personality domains, spirituality, and internalizing symptoms.

Overreporting of acute mystical-type experiences was measured using a 3-item scale. Data for 11 participants was excluded based on strong or extreme endorsement of all three validity items.

Invalid responding was detected using the Infrequency and Unlikely Virtue scales from the Elemental Psychopathy Assessment88.

Participants’ characteristics were measured, including sex, age, personal education level, and parents’ income level.

The Revised-Mystical Experience Questionnaire (RMEQ) was used to assess mystical aspects of participants’ experiences during ayahuasca ceremony. It consists of thirty items and was able to measure four subscales: Mystical, Positive mood, Transcendence of time and space, and Ineffability.

Ego dissolution was measured using the Ego Dissolution Inventory (EDI91), which consists of eight items using a 5-point Likert scale.

Ayahuasca Experience Inventory (AEI) was developed to measure thoughts, feelings, behaviors, and attitudes that arise within ayahuasca ceremonies. The AEI consists of three factors: Clarity, Reappraisal, and Discomfort.

Shamanic elements items were generated using the same method as the AEI and RMEQ, and were administered to 195 participants.

Participants were asked about characteristics of their retreat experience, including the number of ceremonies they consumed ayahuasca, the length of the retreat, the average dosage of ayahuasca, and experiences with other plant medicines.

To reduce redundancy among related experiential variables, exploratory factor analyses were conducted on experiential factor subscales. A mystical experience and reappraisal factor was identified, and a discomfort factor was identified.

Five sets of analyses were conducted to determine the degree to which personality changed in relation to ayahuasca ceremony. These analyses included linear mixed models, moderating effects on time, comparing self- and informant-reported FFM domains, and zero-order correlations among Baseline personality domains and experiential factors.

Power analyses indicated that the self-report sample and the informant-sample were both sufficiently large to detect true differences between timepoints exceeding .11 (Neuroticism), .15 (Extraversion), .15 (Openness), .15 (Agreeableness), and .16 (Conscientiousness) standard deviations.

Acknowledgements

The authors thank all participants for their valuable time, and the Source Research Foundation, Soltara Healing Center, La Medicina, Arkana Spiritual Center, and Heroic Hearts Project for their support.

Additional information

The article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source.