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Ayahuasca

ayahuasca, a plea for the decolonization of psychedelic studies

“We told people that it was in the name of the Holy Spirit, the Father and the Son, but in reality it is in the name of the Sun, the Moon and the Tiger…”

While the potential benefits of psychedelic plant medicines to society still remain largely unrealised, contemporary psychedelic studies risk replicating harmful colonial practices within the territories and communities in which the use of psychedelic plants originate. 

After decades of prohibition, the so-called “psychedelic renaissance” is undertaking a  state-of-the-art exploration of the psychology, neurology and medical approaches associated with the effects and benefits of psychedelics.  The field runs the risk, however, of privileging the voices of mainstream western male researchers over those of the indigenous practitioners whose ancestral knowledge of psychedelics roots back to their origins (George et al, 2020). 

A decolonial approach is essential to the success of the current psychedelic renaissance, as failing to recognize indigenous perspectives as equally valuable to the discussion in the appropriate use of these substances only contributes to deepening the colonial wound within which usage of the plants is interwoven. As academia reconsiders previously taboo subjects (such as mind-altering substances), it has the duty to reconsider also the re-enactment of colonial epistemicide (the killing off of existing systems of knowledge), and give indigenous expertise the space it deserves in scientific research. 

The very old relationship between humanity and the ritual alteration of consciousness is, in indigenous communities, deeply linked to systems of traditional medicine. Nevertheless, in the West, practices associated with mind-altering substances have faced decades of strong political opposition and, as the renaissance unfolds, there are other, more subtle threats being held at bay, specifically the peril inherent in silencing other voices because of their culturally diverse backgrounds. 

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Ayahuasca’s history and its critical entanglement with colonization: 

Ayahuasca, or yagé, is a traditional brew from the Amazon rainforest that contains the classic psychedelic compound DMT. It has a long history of use by indigenous peoples in the Amazon basin, where it is mainly used for ritual and healing purposes, usually in ceremonial settings led by a shaman or curandero. 

Ayahuasca is a particularly complex substance that relies on two intersecting components to deliver its psychedelic effects. Psychotria viridis, or chacruna, is a shrub, the leaves of which contain the DMT. Banisteriopsis caapi is a vine that contains monoamine oxidase (MAO) inhibitors, which prevent MAO enzymes in the stomach from breaking down the DMT as they’d normally do, thus allowing the body to actively absorb it when it is consumed orally. Taking into account the improbability of discovering the function of this particular combination of a shrub and a vine amongst the the tens of thousands of different plant species in the Amazon, along with the preparatory process needed to coax out its psychoactive properties, ayahuasca can be considered an invention, a piece of technology developed by the Amazonian people.  

The indigenous people of the Amazon relate to their surrounding environment in a way that lends itself to developing a great body of ethnobotanical knowledge. Much of the knowledge that has been produced by indigenous people has, however, been the subject of appropriation and biopiracy, as the history of the rainforest cannot be grasped separately from the history of the colonization of the Americas.

One can go back to Western explorers and botanists to trace historically how ayahuasca came to be known outside the jungle, Richard Spruce and Richard Evans Schultes, for instance, were some of the first outsiders to report on indigenous plant medicines. But, by telling and re-telling the story in such a way, a colonial version of history is reinforced where indigenous peoples and their knowledge are passively discovered by Western institutions, their own contribution, skill, and subjectivity neglected, minimized, or reduced to naturalistic fact. 

The history of the Amazon has been shaped by the way that the Western European imagination has interacted with this territory: from the mythic quests to find rivers of gold in the 16th century as the Spanish conquistadors mapped the Amazon river in the search for El Dorado, to the rubber barons of the 20th century who exploited and enslaved hundreds of thousands of indigenous people as they strove to realize enormous profits. The Amazon is a territory that has been perceived as a well of treasures to be extracted and appropriated. 

Today’s deforestation crisis, related to the extraction of precious timber and the clearing of trees for cattle, are an inheritance of old relationships with this land that still conceives of the Amazon as an uninhabited space full of natural wealth and resources. The rainforest has been historically included in the world’s economy only in terms of exploitation, and indigenous communities as well as their knowledge have been objectified in the same way as their land. 

Ayahuasca, curiously, was used during colonial times as a way of resisting and contesting the settler invasion. As the conquistador’s culture demonized indigenous ritual and traditional medicine, ayahuasca was used as a way of exercising and preserving indigenous identity, and was perceived as a repository of cultural memory for the peoples of the Amazon (Leyva, 1991).

At ICPR 2020, Olivia Marcus, David Dupuis, Bia Labate and Daniela Peluso discussed the globlisation of ayahuasca

Other versions of history; Ayahuasca/Yagé and its traditional users:

To trace historically the movement of ayahuasca and other plant medicines one need not rely entirely on the Western explorers and botanists who explored the Amazon and taxonomized its species. Ayahuasca traveled outside of the Amazon via old shamanic networks that for centuries wove an exchange of knowledge and ritual technologies (Pinzón et al., 2004). For instance, the Putumayo department, located in southwest Colombia, is divided into three sub regions: The Upper Putumayo (Andes mountain range), Middle Putumayo (Amazon foothills) and Lower Putumayo (Amazon basin). The Sibundoy Valley which is famous for being home of prominent ayahuasca shamans in Colombia, is located in the Upper Putumayo, a geographical node between the Andes and the Amazon. People who inhabit the area are both settlers and indigenous people who belong to two ethnic groups, the Inga and the Kamentsá

Relations – including shamanic ones – have existed for centuries between the Upper Putumayo (Andes) and the Lower Putumayo (Amazon). The Cofán, Siona and Coreguajes, who are known to be powerful shamans, live at lower elevations where rainforest vegetation flourishes. As ayahuasca cannot grow outside of the tropical forest, shamans from the Upper Putumayo have long traveled down to acquire the brew and, in doing so, maintained a cross-pollinating network that exchanges plants, ritual and healing technologies, and cosmological knowledge (Pinzón et al., 2004). 

In their travels to the Amazon basin, Ingas from the Upper Putumayo learnt the uses and powers of shamanic plants and engaged in shamanic apprenticeships (Pinzón et al., 2004) with the help of shamans from this area. They then transported plants and other ritual devices, including ayahuasca, from the low tropical forest to Sibundoy. The memory of the botanical relationship between shamans was retained in their respective gardens, disseminating and preserving thus the interchange of knowledge between the Amazon and the Andes. 

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Such movement helped inform the transformation of indigenous practices which came into contact with Catholic missionaries and the general mestizo culture of the rest of the Colombian territory. As we can read in the next excerpt from an interview with a shaman from the Sibundoy Valley:

When I was born, the first thing they gave me was three drops of yagé (ayahuasca). We told people that it was in the name of the Holy Spirit, the Father and the Son, but in reality it is in the name of the Sun, the Moon and the Tiger. That’s how my blood began to be painted.” (Pinzón et al. 146 )

As the previous passage shows, the ritual use of ayahuasca in this area was influenced by the dominant Catholic religion, while at the same time acting as a mechanism to contest and resist the colonial apparatus. The previous statement beautifully depicts how indigenous ritual practices were disguised using catholic motifs as a way to preserve silently their identity: Giving three drops of ayahuasca in the name of the Father, the Son and the Holy Spirit, to conceal it was really given in the name of the Sun, the Moon and the Tiger.  

“…Two years later Eliseo was back again, by bus all the way across the country to dip once more into what he saw as the Indian well of magical power” – (Taussig, 1986. p 435)

With this sentence Michael Taussig begins chapter 27 of his book “Shamanism, Colonialism and the Wild Man” (1986) where, “The Indian well of magical power,” was, of course, the Amazon. Since the very first stages of colonization, the Amazon was a screen upon which European minds could project fantastical mirages of imaginary geographies populated by noble, primitive, and superstitious savages. The picture of an ‘Indian well of magical power’ is a reflection of this. A well of vast and mysterious treasures, gold, rubber, magic, and endless resources, where indigenous communities were perceived through a lens of intellectual inferiority.  The Amazon consequently epitomizes and condenses several European fantasies surrounding a mysterious, irrational and exotic Other. 

What Taussig was looking for in that ‘Indian well of magical power’ was ayahuasca shamanism, where the otherness of indigenous knowledge is capable of healing the maladies of the West. It is precisely the same phenomenon seen when the renowned writer William Burroughs went on a journey to find ayahuasca in Colombia, thinking that it might be his ‘final fix’ (Fotiou, 2019).

The same trope is seen with contemporary ayahuasca tourism, where huge numbers of people from all over the world (though predominantly European and American) travel to the Amazon in search of healing through the exotic otherness of ayahuasca (Losonczy & Mesturini, 2010) (Caicedo, 2009). The contemporary medical approaches to ayahuasca and other psychedelic plant medicines follow the same lines, wherein ayahuasca is being researched for its potential to treat some of the most pervasive illnesses of our time, such as depression, anxiety, and addiction (Fotiou 18)(Frecska et al.) (Palhano-Fontes et al.)(Richards) (Watts et al.) (Roseman et al.).

An interdisciplinary future: 

As psychedelic plant medicines re-enter Western culture, researchers in this field must be aware of the colonial history behind these plants and the communities from which they come to avoid perpetuating the same type of intellectual violence that underlies the old notion of the “noble savage” and current practices of biopiracy. As we enter a globalized society, it will be critical to give regard to knowledge that comes from different cultural and ethnic sources, bestowing upon them equal validity in the discussion of the adequate use of these substances. Mainstream psychedelic research will need to encourage and actively include researchers from diverse ethnic backgrounds, as a diversity of voices and perspectives can only contribute to the advancement of science. 

Besides giving credit to indigenous knowledge (which kept this technology alive for at least the past millennium) it is necessary to recognize the contribution of people of color, women, and researchers from Latin American in the development of psychedelic research, as well as to create spaces within which their perspectives can be heard and  included. 

Understanding how to use these substances will, in the end, require an interdisciplinary effort. The cutting-edge research being performed on psychedelics in the fields of neurobiology and psychology will see its most fruitful results by working hand-in-hand with the humanities (anthropology, decolonial studies, religious studies, philosophy, etc.) to avoid the pitfalls inherent in the epistemicide of non-western voices. The task at hand for the humanities is to reflect on the body-politics of knowledge, help give voice to traditional and indigenous ethno-medicine systems, and create the foundation for a renaissance free from harmful colonial appropriation and silencing.

In conclusion, ayahuasca has a lot to offer the world, as current scientific studies continue to prove its therapeutic potential. It, along with other psychedelic plant medicines, have enormous possibilities in the ongoing fight to alleviate psychological and spiritual suffering. The real question, then, is what can we give back, to the Amazon, to the people that inhabit it, to the preservation of their systems of knowledge, to their worldview and culture, to the most diverse ecosystem of the Earth?

What can we give back? 

References:

1. Caicedo, Alhena. Nuevos chamanismos Nueva Era. 2009, p. 18.
2. Fotiou, Evgenia. ‘The Role of Indigenous Knowledges in Psychedelic Science’. Journal of Psychedelic Studies, vol. 4, no. 1, Dec. 2019, pp. 16–23. DOI.org (Crossref), doi:10.1556/2054.2019.031
3. Frecska, Ede, et al. ‘The Therapeutic Potentials of Ayahuasca: Possible Effects against Various Diseases of Civilization’. Frontiers in Pharmacology, vol. 7, Mar. 2016. DOI.org (Crossref), doi:10.3389/fphar.2016.00035
4. George, Jamilah R., et al. ‘The Psychedelic Renaissance and the Limitations of a White-Dominant Medical Framework: A Call for Indigenous and Ethnic Minority Inclusion’. Journal of Psychedelic Studies, vol. 4, no. 1, Mar. 2020, pp. 4–15. DOI.org (Crossref), doi:10.1556/2054.2019.015
5. Leiva, A., Guerrero, H., Pardo, M., JUNCOSA, J., & AMODIO, E. (1991). Los espíritus aliados: chamanismo y curación en los pueblos indios de Sudamérica. Ediciones Abya Yala, Quito, (31). p. 47
6. Losonczy, Anne-Marie, and Silvia Mesturini. ‘La Selva Viajera: Rutas del chamanismo ayahuasquero entre Europa y América’. Religião & Sociedade, vol. 30, no. 2, 2010, pp. 164–83. Crossref, doi:10.1590/S0100-85872010000200009
7. Mignolo, Walter D. ‘Epistemic Disobedience, Independent Thought and Decolonial Freedom’. Theory, Culture & Society, vol. 26, no. 7–8, Dec. 2009, pp. 159–81. DOI.org (Crossref), doi:10.1177/0263276409349275
8. Miller, M. J., Albarracin-Jordan, J., Moore, C., & Capriles, J. M. (2019). Chemical evidence for the use of multiple psychotropic plants in a 1,000-year-old ritual bundle from South America. Proceedings of the National Academy of Sciences, 116(23), 11207-11212
9. Palhano-Fontes, Fernanda, et al. ‘The Psychedelic State Induced by Ayahuasca Modulates the Activity and Connectivity of the Default Mode Network’. PLOS ONE, edited by Dewen Hu, vol. 10, no. 2, Feb. 2015, p. e0118143. DOI.org (Crossref), doi:10.1371/journal.pone.0118143
10. Pinzón, Carlos, et al. ‘El Jardín de La Ciencia En El Valle de Sibundoy’. Mundos En Red: La Cultura Popular Frente a Los Retos Del Siglo XXI, 2004, pp. 139–99
11. Richards, William A. ‘Psychedelic Psychotherapy: Insights From 25 Years of Research’. Journal of Humanistic Psychology, vol. 57, no. 4, July 2017, pp. 323–37. DOI.org (Crossref), doi:10.1177/0022167816670996
12. Roseman, Leor, et al. ‘Emotional Breakthrough and Psychedelics: Validation of the Emotional Breakthrough Inventory’. Journal of Psychopharmacology, vol. 33, no. 9, Sept. 2019, pp. 1076–87. DOI.org (Crossref), doi:10.1177/0269881119855974
13. Taussig, Michael. Shamanism, Colonialism and the Wild Man. The University of Chicago Press, 1986
14. Watts, Rosalind, et al. ‘Patients’ Accounts of Increased “Connectedness” and “Acceptance” After Psilocybin for Treatment-Resistant Depression’. Journal of Humanistic Psychology, vol. 57, no. 5, Sept. 2017, pp. 520–64. DOI.org (Crossref), doi:10.1177/0022167817709585

When Plants Dream: Ayahuasca, Amazonian Shamanism and the Global Psychedelic Renaissance

When Plants Dream: Ayahuasca, Amazonian Shamanism and the Global Psychedelic Renaissance. David Pinchbeck. Watkins Publishing. ISBN: 9781786780799

Focusing specifically on Ayahuasca, the authors look at the economic, social, political, cultural, and environmental impact that this plant is having on society, both good and bad. This is the first book of its kind to look at the science and expanding culture of ayahuasca, from its historical use to its appropriation by the West and the impact it is having on cultures beyond the Amazon.

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Psychedelic Medicine: The Healing Powers of LSD, MDMA, Psilocybin, and Ayahuasca

PSYCHEDELIC MEDICINE: THE HEALING POWERS OF LSD, MDMA, PSILOCYBIN, AND AYAHUASCA. Dr. Richard Louis Miller. Park Street Press. ISBN: 978-1620556979

Clinical psychologist Dr. Richard Louis Miller discusses what is happening today in psychedelic medicine. Dr. Miller and his contributors explore the ongoing efforts to restore psychedelic therapies to the health field. They also discuss the newly shifting political climate and the push for new research, offering hope for an end to the War on Drugs and a potential renaissance of research into psychedelic medicines around the world.

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Risk assessment of ayahuasca use in a religious context: self-reported risk factors and adverse effects

Abstract

Objective: Whether for spiritual, recreational, or potential therapeutic use, interest in ayahuasca has grown remarkably. Ayahuasca’s main active substances are N,N-dimethyltryptamine and certain monoamine oxidase inhibitor β-carbolines. Possible drug interactions are a major concern, and research is lacking in this area. The objective of this study was to evaluate the safety of ritual ayahuasca use regarding adverse effects and risk factors.

Methods: In this cross-sectional study, ayahuasca users from a religious institution answered an online questionnaire about its safety. Adverse effects, safety measures, and possible risk factors (psychiatric diagnosis and medications) were investigated.

Results: The most frequent adverse effects among the 614 participants were transient gastrointestinal effects (nausea and vomiting). Fifty participants self-reported a psychiatric diagnosis (depression and anxiety were the most prevalent), and these participants experienced adverse effects more frequently. Psychiatric medication use was reported by 31 participants. No indication of increased adverse effects due to drug-drug interactions was found.

Conclusion: A minority of participants reported being very negatively affected by persistent adverse effects. Psychiatric medication use while participating in ayahuasca rituals was not associated with increased adverse effects. For the most part, the institution’s practices seem sufficient to prevent exacerbated reactions. Future studies may focus on negatively affected users.

Durante, Í., Dos Santos, R. G., Bouso, J. C., & Hallak, J. E. (2021). Risk assessment of ayahuasca use in a religious context: self-reported risk factors and adverse effects. Revista brasileira de psiquiatria (Sao Paulo, Brazil : 1999), 43(4), 362–369. https://doi.org/10.1590/1516-4446-2020-0913

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Effects of Ayahuasca on the Recognition of Facial Expressions of Emotions in Naive Healthy Volunteers: A Pilot, Proof-of-Concept, Randomized Controlled Trial

Abstract

Background: The recognition of emotions in facial expressions (REFE) is a core aspect of social cognition. Previous studies with the serotonergic hallucinogens lysergic acid diethylamide and psilocybin showed that these drugs reduced the recognition of negative (fear) faces in healthy volunteers. This trial assessed the acute and prolonged effects of a single dose of ayahuasca on the REFE.

Methods: Twenty-two healthy volunteers participated in a pilot, proof-of-concept, randomized trial. Study variables included a REFE task performed before and 4 hours after drug intake, subjective effects (self-reports/observer impressions), tolerability measures (cardiovascular measures, self-reports), and brain-derived neurotrophic factor plasma levels. The REFE task was applied again 1, 7, 14, and 21 days and 3 months after drug intake. Stability of ayahuasca alkaloids during the study was also assessed (room temperature, 18 months).

Findings: Compared with placebo, ayahuasca did not modify the REFE. No significant effects were observed on cardiovascular measures and brain-derived neurotrophic factor levels. Volunteers reported visual effects, tranquility/relaxation, and well-being, with few reports of transient anxiety/confusion. Ayahuasca was well tolerated, producing mainly nausea, gastrointestinal discomfort, and vomiting. A significant time-dependent deterioration of alkaloids was observed, especially for dimethyltryptamine.

Conclusions: Absence of significant effects on the REFE task could be due to lack of effects of ayahuasca (at the doses used), alkaloid degradation, learning effects, and the high educational level of the sample. Further trials with different samples are needed to better understand the effects of ayahuasca and other serotonergic hallucinogens on the REFE. Future trials should improve methods to guarantee the stability of ayahuasca alkaloids.

Rocha, J. M., Rossi, G. N., de Lima Osório, F., Bouso, J. C., de Oliveira Silveira, G., Yonamine, M., Campos, A. C., Bertozi, G., Cecílio Hallak, J. E., & Dos Santos, R. G. (2021). Effects of Ayahuasca on the Recognition of Facial Expressions of Emotions in Naive Healthy Volunteers: A Pilot, Proof-of-Concept, Randomized Controlled Trial. Journal of clinical psychopharmacology, 41(3), 267–274. https://doi.org/10.1097/JCP.0000000000001396

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Examining changes in personality following shamanic ceremonial use of ayahuasca

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 dzself-reportT1-T2 = – 1.00; dzself-reportT1-T3 = – .85; dzinformant-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.

Weiss, B., Miller, J. D., Carter, N. T., & Keith Campbell, W. (2021). Examining changes in personality following shamanic ceremonial use of ayahuasca. Scientific reports, 11(1), 6653. https://doi.org/10.1038/s41598-021-84746-0

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Hallucinogenic/psychedelic 5HT2A receptor agonists as rapid antidepressant therapeutics: Evidence and mechanisms of action

Abstract

Major depressive disorder (MDD) is among the most prevalent mental health disorders worldwide, and it is associated with a reduced quality of life and enormous costs to health care systems. Available drug treatments show low-to-moderate response in most patients, with almost a third of patients being non-responders (treatment-resistant). Furthermore, most currently available medications need several weeks to achieve therapeutic effects, and the long-term use of these drugs is often associated with significant unwanted side effects and resultant reductions in treatment compliance. Therefore, more effective, safer, and faster-acting antidepressants with enduring effects are needed. Together with ketamine, psychedelics (or classic or serotoninergic hallucinogens) such as lysergic acid diethylamide (LSD), psilocybin, and ayahuasca are among the few compounds with recent human evidence of fast-acting antidepressant effects. Several studies in the 1950s to 1970s reported antidepressive and anxiolytic effects of these drugs, which are being confirmed by modern trials (LSD, one trial; psilocybin, five trials; ayahuasca, two trials). The effects of these drugs appear to be produced primarily by their agonism at serotonin (5-hydroxytryptamine, 5-HT) receptors, especially the 5-HT2A receptor. Considering the overall burden of MDD and the necessity of new therapeutic options, the promising (but currently limited) evidence of safety and efficacy of psychedelics has encouraged the scientific community to explore more fully their beneficial effects in MDD.

Dos Santos, R. G., Hallak, J. E., Baker, G., & Dursun, S. (2021). Hallucinogenic/psychedelic 5HT2A receptor agonists as rapid antidepressant therapeutics: Evidence and mechanisms of action. Journal of psychopharmacology (Oxford, England), 35(4), 453–458. https://doi.org/10.1177/0269881120986422

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A placebo-controlled study of the effects of ayahuasca, set and setting on mental health of participants in ayahuasca group retreats

Abstract

Ayahuasca is a plant concoction containing N,N-dimethyltryptamine (DMT) and certain β-carboline alkaloids from South America. Previous research in naturalistic settings has suggested that ingestion of ayahuasca can improve mental health and well-being; however, these studies were not placebo controlled and did not control for the possibility of expectation bias. This naturalistic observational study was designed to assess whether mental health changes were produced by ayahuasca or by set and setting. Assessments were made pre- and post-ayahuasca sessions in 30 experienced participants of ayahuasca retreats hosted in the Netherlands, Spain, and Germany. Participants consumed ayahuasca (N = 14) or placebo (N = 16). Analysis revealed a main effect of time on symptoms of depression, anxiety, and stress. Compared to baseline, symptoms reduced in both groups after the ceremony, independent of treatment. There was a main treatment × time interaction on implicit emotional empathy, indicating that ayahuasca increased emotional empathy to negative stimuli. The current findings suggest that improvements in mental health of participants of ayahuasca ceremonies can be driven by non-pharmacological factors that constitute a placebo response but also by pharmacological factors that are related to the use of ayahuasca. These findings stress the importance of placebo-controlled designs in psychedelic research and the need to further explore the contribution of non-pharmacological factors to the psychedelic experience.

Uthaug, M. V., Mason, N. L., Toennes, S. W., Reckweg, J. T., de Sousa Fernandes Perna, E. B., Kuypers, K., van Oorsouw, K., Riba, J., & Ramaekers, J. G. (2021). A placebo-controlled study of the effects of ayahuasca, set and setting on mental health of participants in ayahuasca group retreats. Psychopharmacology, 238(7), 1899–1910. https://doi.org/10.1007/s00213-021-05817-8

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Within-treatment changes in a novel addiction treatment program using traditional Amazonian medicine

Abstract

Aims: The therapeutic use of psychedelics is regaining scientific momentum, but similarly psychoactive ethnobotanical substances have a long history of medical (and other) uses in indigenous contexts. Here we aimed to evaluate patient outcomes in a residential addiction treatment center that employs a novel combination of Western and traditional Amazonian methods.

Methods: The study was observational, with repeated measures applied throughout treatment. All tests were administered in the center, which is located in Tarapoto, Peru. Data were collected between 2014 and 2015, and the study sample consisted of 36 male inpatients who were motivated to seek treatment and who entered into treatment voluntarily. Around 58% of the sample was from South America, 28% from Europe, and the remaining 14% from North America. We primarily employed repeated measures on a psychological test battery administered throughout treatment, measuring perceived stress, craving frequency, mental illness symptoms, spiritual well-being, and physical and emotional health. Addiction severity was measured on intake, and neuropsychological performance was assessed in a subsample from intake to at least 2 months into treatment.

Results: Statistically significant and clinically positive changes were found across all repeated measures. These changes appeared early in the treatment and were maintained over time. Significant improvements were also found for neuropsychological functioning.

Conclusion: These results provide evidence for treatment safety in a highly novel addiction treatment setting, while also suggesting positive therapeutic effects.

O’Shaughnessy, D. M., Berlowitz, I., Rodd, R., Sarnyai, Z., & Quirk, F. (2021). Within-treatment changes in a novel addiction treatment program using traditional Amazonian medicine. Therapeutic advances in psychopharmacology, 11, 2045125320986634. https://doi.org/10.1177/2045125320986634

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The acute effects of classic psychedelics on memory in humans

Abstract

Rationale: Memory plays a central role in the psychedelic experience. The spontaneous recall and immersive reliving of autobiographical memories has frequently been noted by researchers and clinicians as a salient phenomenon in the profile of subjective effects of classic psychedelic drugs such as psilocybin, LSD, and ayahuasca. The ability for psychedelics to provoke vivid memories has been considered important to their clinical efficacy.

Objective: This review aims to examine and aggregate the findings from experimental, observational, and qualitative studies on the acute modulation of memory by classic psychedelics in humans.

Method: A literature search was conducted using PubMed and PsycInfo as well as manual review of references from eligible studies. Publications reporting quantitative and/or qualitative findings were included; animal studies and case reports were excluded.

Results: Classic psychedelics produce dose-dependently increasing impairments in memory task performance, such that low doses produce no impairment and higher doses produce increasing levels of impairment. This pattern has been observed in tasks assessing spatial and verbal working memory, semantic memory, and non-autobiographical episodic memory. Such impairments may be less pronounced among experienced psychedelic users. Classic psychedelics also increase the vividness of autobiographical memories and frequently stimulate the recall and/or re-experiencing of autobiographical memories, often memories that are affectively intense (positively or negatively valenced) and that had been avoided and/or forgotten prior to the experience.

Conclusions: Classic psychedelics dose-dependently impair memory task performance but may enhance autobiographical memory. These findings are relevant to the understanding of psychological mechanisms of action of psychedelic-assisted psychotherapy.

Healy C. J. (2021). The acute effects of classic psychedelics on memory in humans. Psychopharmacology, 238(3), 639–653. https://doi.org/10.1007/s00213-020-05756-w

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