Neural and subjective effects of inhaled N,N-dimethyltryptamine in natural settings

The Effects of Ayahuasca on Psychological Disorders: A Systematic Literature Review

Ayahuasca is an original Amazonian brew made from the vines and leaves of Psychotroa viridis and Banisteriopsis caapi. Both P. viridis and B. caapi give this brew its unique psychedelic properties which have been revered over centuries. In recent years, ayahuasca has gained attention as a potential therapeutic tool for mental health disorders, including substance abuse and depression. The uniqueness of ayahuasca's therapeutic potential is that it is an amalgamation of its biochemical makeup and the ritual guided by a shaman, along with the interpretation of the participant of their experience. The boom of "ayahuasca tourism" has brought forth testimonies of feeling "cured" of depression, and substance abuse and an improvement in overall well-being. This systematic literature review focuses on summarizing the recently available research on the effectiveness of ayahuasca as a treatment for depression, anxiety, substance abuse, eating disorders, and post-traumatic stress disorder. It also focuses on understanding the effects it has on personality traits that play a significant role in the manifestation of the above-listed mental health conditions effects. Additionally, the review investigates the importance and role the ritual itself plays, often described as the "mystical experience". This systematic literature review aims to explore the current state of knowledge regarding the use of ayahuasca for numerous mental health conditions by analyzing medical research papers published no earlier than September 2017 to no later than May 2023 from Google Scholar and PubMed. A total of 43 articles met the criteria and were used for detailed analysis. This review will synthesize the findings of the studies, examining the potential therapeutic effects of ayahuasca on multiple mental health disorders, the significance of the "mystical experience," and the mechanisms of action underlying its effects. Through the review, ayahuasca proves to be a worthwhile therapeutic tool that if used in the right setting influences mind, body, and spirit. It is important to note that most studies used in this article relied on surveys and self-reporting proving to be a limitation as no clear standard has been achieved to test the efficacy of ayahuasca. The respect for the culture and origin needs to be retained as Western medicine dwells deeper into ayahuasca's benefits.

Safety and tolerability of inhaled N,N-Dimethyltryptamine (BMND01 candidate): A phase I clinical trial

Psychedelics are being increasingly examined for their therapeutic potential in mood disorders. While the acute effects of ayahuasca, psilocybin, and lysergic acid diethylamide (LSD) last over several hours, inhaled N,N-Dimethyltryptamine (DMT) effects last around 10 min, which might provide a cost- and time-effective alternative to the clinical application of oral psychedelics. We aimed at investigating the safety and tolerability of inhaled DMT (BMND01 candidate). We recruited 27 healthy volunteers to receive a first, lower dose and a second, higher dose (5/20 mg, 7.5/30 mg, 10/40 mg, 12.5/50 mg, or 15/60 mg) of inhaled DMT in an open-label, single-ascending, fixed-order, dose-response study design. We investigated subjective experiences (intensity, valence, and phenomenology), physiological effects (blood pressure, heart rate, respiratory rate, blood oxygen saturation, body temperature), biochemical markers (liver, kidney, and metabolic functions), and adverse events during the acute and post-acute effects of DMT. DMT dose-dependently increased intensity, valence and perceptual ratings. There was a mild, transient, and self-limited increase in blood pressure and heart rate. There were no changes in safety blood biomarkers and no serious adverse events. DMT dose-dependently enhanced subjective experiences and positive valence. Inhaled DMT might be an efficient, non-invasive, safe route of administration, which might simplify the clinical use of this substance. This is the first clinical trial to test the effects of inhaled DMT (BMND01 candidate).

Synthetic surprise as the foundation of the psychedelic experience

Psychedelic agents, such as LSD and psilocybin, induce marked alterations in consciousness via activation of the 5-HT2A receptor (5-HT2ARs). We hypothesize that psychedelics enforce a state of synthetic surprise through the biased activation of the 5-HTRs system. This idea is informed by recent insights into the role of 5-HT in signaling surprise. The effects on consciousness, explained by the cognitive penetrability of perception, can be described within the predictive coding framework where surprise corresponds to prediction error, the mismatch between predictions and actual sensory input. Crucially, the precision afforded to the prediction error determines its effect on priors, enabling a dynamic interaction between top-down expectations and incoming sensory data. By integrating recent findings on predictive coding circuitry and 5-HT2ARs transcriptomic data, we propose a biological implementation with emphasis on the role of inhibitory interneurons. Implications arise for the clinical use of psychedelics, which may rely primarily on their inherent capacity to induce surprise in order to disrupt maladaptive patterns.

Paradoxical pharmacological dissociations result from drugs that enhance delta oscillations but preserve consciousness

Low-frequency (<4 Hz) neural activity, particularly in the delta band, is generally indicative of loss of consciousness and cortical down states, particularly when it is diffuse and high amplitude. Remarkably, however, drug challenge studies of several diverse classes of pharmacological agents-including drugs which treat epilepsy, activate GABA_B receptors, block acetylcholine receptors, or produce psychedelic effects-demonstrate neural activity resembling cortical down states even as the participants remain conscious. Of those substances that are safe to use in healthy volunteers, some may be highly valuable research tools for investigating which neural activity patterns are sufficient for consciousness or its absence.

Orally Active Forms of DMT, 5-MeO-DMT, and Long-Acting MDMA for the Treatment of Neuropsychiatric Disorders

This Patent Highlight describes derivatives of DMT, 5-MeO-DMT, and MDMA that are metabolically converted to biologically active analogs. When these prodrugs are administered to a subject, they potentially could be used therapeutically in conditions associated with neurological diseases. Furthermore, the disclosure provides methods to potentially treat conditions comprising major depressive disorder, post-traumatic stress disorder, Alzheimer's disease, Parkinson's disease, schizophrenia, frontotemporal dementia, Parkinson's dementia, dementia, Lewy body dementia, multiple system atrophy, or substance abuse.

N,N-dimethyltryptamine affects electroencephalography response in a concentration-dependent manner-A pharmacokinetic/pharmacodynamic analysis

N,N-dimethyltryptamine (DMT) is a psychedelic substance and is being used as a research tool in investigations of the neurobiology behind the human consciousness using different brain imaging techniques. The effects of psychedelics have commonly been studied using electroencephalography (EEG) and have been shown to produce suppression of alpha power and increase in signal diversity. However, the relationship between DMT exposure and its EEG effects has never been quantified. In this work, a population pharmacokinetic/pharmacodynamic analysis was performed investigating the relationship between DMT plasma concentrations and its EEG effects. Data were obtained from a clinical study where DMT was administered by intravenous bolus dose to 13 healthy subjects. The effects on alpha power, beta power, and Lempel-Ziv complexity were evaluated. DMT was shown to fully suppress alpha power. Beta power was only partially suppressed, whereas an increase in Lempel-Ziv complexity was observed. The relationship between plasma concentrations and effects were described using effect compartment models with sigmoidal maximum inhibitory response or maximum stimulatory response models. Values of the concentration needed to reach half of the maximum response (EC_50,e ) were estimated at 71, 137, and 54 nM for alpha, beta, and Lempel-Ziv complexity, respectively. A large amount of between-subject variability was associated with both beta power and Lempel-Ziv complexity with coefficients of variability of 75% and 77% for the corresponding EC_50,e values, respectively. Alpha power appeared to be the most robust response, with a between-subject variability in EC_50,e of 29%. Having a deeper understanding of these processes might prove beneficial in choosing appropriate doses and response biomarkers in the future clinical development of DMT.

Psychedelic-Assisted Neuroplasticity for the Treatment of Mental Health Disorders

The renaissance of research into psychedelics class of drugs has renewed interest for a possible psychedelic clinical therapy for treating psychiatric conditions such as treatment-resistant depression, major depressive-disorder, post-traumatic stress disorder, and other neuropsychiatric diseases. Psychedelics are known to stimulate neurogenesis and gliogenesis, reduce inflammation, and ameliorate oxidative stress, which makes them promising candidates for therapeutics in psychiatric, neurodegenerative, and movement disorders. The patent highlight showcase methods for treating mental health disorders and promoting neural plasticity.

The Altered States Database: Psychometric data from a systematic literature review

In this paper, we present the development of the Altered States Database (ASDB), an open-science project based on a systematic literature review. The ASDB contains psychometric questionnaire data on subjective experiences of altered states of consciousness (ASC) induced by pharmacological and non-pharmacological methods. The systematic review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Scientific journal articles were identified through PubMed and Web of Science. We included studies that examined ASC using the following validated questionnaires: Altered States of Consciousness Rating Scale (APZ, 5D-ASC, 11-ASC), Phenomenology of Consciousness Inventory (PCI), Hallucinogen Rating Scale (HRS), or Mystical Experience Questionnaire (MEQ30). The systematic review resulted in the inclusion of a total of 165 journal articles, whereof questionnaire data was extracted and is now available on the Open Science Framework (OSF) website (https://osf.io/8mbru) and on the ASDB website (http://alteredstatesdb.org), where questionnaire data can be easily retrieved and visualized. This data allows the calculation of comparable psychometric values of ASC experiences and of dose-response relationships of substances inducing ASC.

Measurement(s)	Psychometric questionnaire data
Technology Type(s)	Systematic literature review (PRISMA)
Sample Characteristic - Organism	Human

Changes in mental health, wellbeing and personality following ayahuasca consumption: Results of a naturalistic longitudinal study

Background: Naturalistic and placebo-controlled studies suggest ayahuasca, a potent psychedelic beverage originating from Indigenous Amazonian tradition, may improve mental health, alter personality structure, and reduce alcohol and drug intake. To better understand ayahuasca’s therapeutic potential and to identify factors that influence therapeutic efficacy, we conducted a naturalistic, longitudinal study of facilitated ayahuasca consumption in naïve participants using a comprehensive battery of self-report questionnaires.

Materials and Methods: Ayahuasca naive individuals registering for ayahuasca ceremonies were asked to complete a range of validated questionnaires assessing mental health, alcohol/cannabis use, relationships, personality, and connection to self and spirituality, prior to and 1 month after attending an ayahuasca ceremony. Data for two mental health measures (the DASS-21 and PANAS) and acute subjective effects via the MEQ-30 were also assessed 7 days post-ceremony. Repeated measures ANOVA were used to examine pre-to-post changes, and Pearson correlations explored predictors of improvement in outcomes.

Results: Fifty-three attendees (32 women, 21 men) completed pre and post ayahuasca assessments with 55.6% of the sample reporting a complete mystical experience based on the MEQ-30. One-month post-ayahuasca, significant reductions were identified in depression, anxiety, stress, alcohol and cannabis use, body dissociation, accepting external influence, self-alienation, impulsivity, and negative affect/emotionality. Significant increases were identified in positive mood, self-efficacy, authentic living, extraversion, agreeableness, open-mindedness, spirituality, and satisfaction with relationships. While facets of the mystical experience held little predictive validity on outcome measures, baseline traits, particularly high negative emotionality and body dissociation, and low sense of self-efficacy, robustly predicted improvements in mental health and alcohol/cannabis use, and alterations in personality structure which are linked to better mental health.

Discussion: This study suggests facilitated ayahuasca consumption in naïve participants may precipitate wide-ranging improvements in mental health, relationships, personality structure, and alcohol use. Associations between baseline traits and therapeutic improvements mark an important first step toward personalized, precision-based medicine and warrant randomized controlled trials to confirm and elaborate on these findings.

Contribution Statement: Longitudinal, observational studies and randomized clinical control trials suggest ayahuasca may exert therapeutic effects on mental health and alcohol/cannabis use, and alter personality structure. However, it is unclear if improvements are diagnosis-specific and factors that predict therapeutic gains have yet to be extensively elucidated. This longitudinal, observational study examined the effects of facilitated ayahuasca consumption in naive participants on mental health, alcohol and substance use/abuse, personality traits, relationships, and connection to self and spirituality. We found wide-ranging improvements 1-month post-treatment across these domains, and identified baseline traits which predict pre-to-post changes on primary outcome measures. Improvements were not diagnostic-specific, suggesting ayahuasca may be generally efficacious. Personality traits, body dissociation, and self-efficacy were strong predictors of therapeutic improvements, marking an important first step toward personalized, precision-based medicine. Randomized controlled trials are warranted to confirm and elaborate on these findings.

Microdosing with psilocybin mushrooms: a double-blind placebo-controlled study

The use of low sub-perceptual doses of psychedelics ("microdosing") has gained popularity in recent years. Although anecdotal reports claim multiple benefits associated with this practice, the lack of placebo-controlled studies severely limits our knowledge of microdosing and its effects. Moreover, research conducted in standard laboratory settings could fail to capture the motivation of individuals engaged or planning to engage in microdosing protocols, thus underestimating the likelihood of positive effects on creativity and cognitive function. We recruited 34 individuals starting to microdose with psilocybin mushrooms (Psilocybe cubensis), one of the materials most frequently used for this purpose. Following a double-blind placebo-controlled experimental design, we investigated the acute and short-term effects of 0.5 g of dried mushrooms on subjective experience, behavior, creativity (divergent and convergent thinking), perception, cognition, and brain activity. The reported acute effects were significantly more intense for the active dose compared to the placebo, but only for participants who correctly identified their experimental condition. These changes were accompanied by reduced EEG power in the theta band, together with preserved levels of Lempel-Ziv broadband signal complexity. For all other measurements there was no effect of microdosing except for few small changes towards cognitive impairment. According to our findings, low doses of psilocybin mushrooms can result in noticeable subjective effects and altered EEG rhythms, but without evidence to support enhanced well-being, creativity and cognitive function. We conclude that expectation underlies at least some of the anecdotal benefits attributed to microdosing with psilocybin mushrooms.

N,N-dimethyltryptamine and Amazonian ayahuasca plant medicine

OBJECTIVE

Reports have indicated possible uses of ayahuasca for the treatment of conditions including depression, addictions, post-traumatic stress disorder, anxiety and specific psychoneuroendocrine immune system pathologies. The article assesses potential ayahuasca and N,N-dimethyltryptamine (DMT) integration with contemporary healthcare. The review also seeks to provide a summary of selected literature regarding the mechanisms of action of DMT and ayahuasca; and assess to what extent the state of research can explain reports of unusual phenomenology.

DESIGN

A narrative review.

RESULTS

Compounds in ayahuasca have been found to bind to serotonergic receptors, glutaminergic receptors, sigma-1 receptors, trace amine-associated receptors, and modulate BDNF expression and the dopaminergic system. Subjective effects are associated with increased delta and theta oscillations in amygdala and hippocampal regions, decreased alpha wave activity in the default mode network, and stimulations of vision-related brain regions particularly in the visual association cortex. Both biological processes and field of consciousness models have been proposed to explain subjective effects of DMT and ayahuasca, however, the evidence supporting the proposed models is not sufficient to make confident conclusions. Ayahuasca plant medicine and DMT represent potentially novel treatment modalities.

CONCLUSIONS

Further research is required to clarify the mechanisms of action and develop treatments which can be made available to the general public. Integration between healthcare research institutions and reputable practitioners in the Amazon is recommended.

Language as a Window Into the Altered State of Consciousness Elicited by Psychedelic Drugs

Psychedelics are drugs capable of eliciting profound alterations in the subjective experience of the users, sometimes with long-lasting consequences. Because of this, psychedelic research tends to focus on human subjects, given their capacity to construct detailed narratives about the contents of their consciousness experiences. In spite of its relevance, the interaction between serotonergic psychedelics and language production is comparatively understudied in the recent literature. This review is focused on two aspects of this interaction: how the acute effects of psychedelic drugs impact on speech organization regardless of its semantic content, and how to characterize the subjective effects of psychedelic drugs by analyzing the semantic content of written retrospective reports. We show that the computational characterization of language production is capable of partially predicting the therapeutic outcome of individual experiences, relate the effects elicited by psychedelics with those associated with other altered states of consciousness, draw comparisons between the psychedelic state and the symptomatology of certain psychiatric disorders, and investigate the neurochemical profile and mechanism of action of different psychedelic drugs. We conclude that researchers studying psychedelics can considerably expand the range of their potential scientific conclusions by analyzing brief interviews obtained before, during and after the acute effects. Finally, we list a series of questions and open problems that should be addressed to further consolidate this approach.

Predictors and potentiators of psychedelic-occasioned mystical experiences

Mystical experiences are often described as being among the most profound and meaningful events of a person’s life. Their occurrence, while a normal but uncommon phenomenon, is reliably occasioned by psychedelic substances under the appropriate conditions, although care is needed around the context of usage to help ensure safe and beneficial experiences. The occurrence of mystical experiences in psychedelic sessions is a key mediator of the sustained psychological benefits reported in both healthy and clinical populations. Certain factors including set and setting, drug dosage, trait absorption, drug type, intention and states of surrender and acceptance all predict or influence the occurrence of mystical experiences. Various additional factors may further contribute to the occurrence and intensity of mystical experiences and enhance their long-term benefits, including music, meditation and spiritual practices and nature-based settings. This review examines these factors and considers how they might be optimised to increase the chances of a mystical experience occurring, while also considering factors that are negatively associated with mystical experiences with suggestions on how these might be mitigated where applicable. Finally, potential future research avenues for furthering our knowledge of psychedelic mystical experiences and how their benefits might be enhanced is suggested. Maximising the potential for the occurrence of mystical experiences is an important aspect of the beneficial application of psychedelics.

Effects of Setting on Psychedelic Experiences, Therapies, and Outcomes: A Rapid Scoping Review of the Literature

The health and well-being impacts of art and aesthetic experiences have been rigorously studied by a range of disciplines, including cognitive neuroscience, psychiatry, public health, and translational clinical research. These experiences, encompassed in the concepts of set and setting, have long been claimed to be pivotal in determining the acute and enduring effects of psychedelic experiences. Responding to the field's longstanding emphasis on the role and value of setting, a rapid scoping review was undertaken to identify the extent to which effects of setting and aesthetics on psychedelic experiences and therapies have been explicitly studied. It offers an analysis of the strengths and limitations of the extant literature and discusses evidentiary gaps as well as evidentiary opportunities for the field. The 43 included studies indicate apparent consensus regarding the importance of setting in psychedelic therapies, as well as consistent interest in theorizing about these effects. However, this consensus has yet to generate consistent, prospective, rigorous tests of setting and its complexities. As a result, the field continues to lack understanding or agreement regarding the effects of various specific elements of setting, the mechanisms by which they affect outcomes, for whom these effects occur, under what circumstances, given what conditions, and other critical factors. Further studies of setting and aesthetics in the context of psychedelic therapies are likely to not only improve these therapies and their delivery, but also inform considerations of setting and aesthetics for non-psychedelic interventions.

Administration of N,N-dimethyltryptamine (DMT) in psychedelic therapeutics and research and the study of endogenous DMT

As with all drugs, the route, form, and/or dose of a substance administered or applied can play a defining role in its overall pharmacology and use as a therapeutic. This review will focus on these factors as they relate to the psychedelic N,N-dimethyltryptamine (DMT). It will examine the positive and negative aspects of different formulations and routes of administration of DMT and the observed effects from such administrations in the form of ayahuasca teas; oral "pharmahuasca"; injections by intravenous (IV) and intramuscular (IM) routes; inhalation, insufflation; and other routes; and high-dose, low-dose, and "micro-dose" effects. The review will consider possible oral route of administration alternatives that would not require concomitant use of a monoamine oxidase inhibitor. The review will then address the current research findings for DMT from in vivo and in vitro studies as well as the possibility that these findings may be revealing the role of endogenous DMT in normal brain function.

Baseline Power of Theta Oscillations Predicts Mystical-Type Experiences Induced by DMT in a Natural Setting

N,N-Dimethyltryptamine (DMT) is a classic psychedelic capable of inducing short-lasting but profound changes in consciousness. As with other psychedelics, the experience induced by DMT strongly depends upon contextual factors, yet the neurobiological determinants of this variability remain unknown. The present study investigated changes in neural oscillations elicited by inhaled DMT, and whether baseline electroencephalography (EEG) recordings could predict the subjective effects reported by the participants. Healthy volunteers (N = 35) were measured with EEG before and during the acute effects of DMT consumed in a natural setting. Source-localized neural oscillations were correlated with the results of multiple questionnaires employed to assess the subjective effects of the drug. DMT resulted in a marked reduction of alpha and beta oscillations, and increased posterior spectral power in the delta, theta and gamma bands. The power of fronto-temporal theta oscillations was inversely correlated with scales indexing feelings of unity and transcendence, which are an integral part of the phenomenology of mystical-type experiences. The robustness of these results was supported using a machine learning model for regression trained and tested following a cross-validation procedure. These results are consistent with the observation that the state of mind prior to consuming a psychedelic drug influences the ensuing subjective experience of the user. They also suggest that baseline EEG screenings before administration of a serotonergic psychedelic could be useful to estimate the likelihood of inducing mystical-type experiences, previously linked to sustained positive effects in well-being and improved outcome of therapeutic interventions.