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Gonçalves J, Luís Â, Gallardo E, Duarte AP. A Systematic Review on the Therapeutic Effects of Ayahuasca. PLANTS (BASEL, SWITZERLAND) 2023; 12:2573. [PMID: 37447135 DOI: 10.3390/plants12132573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 07/04/2023] [Accepted: 07/05/2023] [Indexed: 07/15/2023]
Abstract
Traditional therapies, resorting to the use of plants, have acquired a great demand over the years, both for economic reasons and the preference for natural treatments. Some studies suggest that ayahuasca may have beneficial properties in treating some physical and psychological imbalances. Thus, we carried out a systematic review of studies published up to December 2022, where these themes were addressed. The search was carried out in the PubMed database, and only studies written in English and published in peer-reviewed journals were included. Thus, 228 publications were identified, of which 66 were included in the present study. The reviewed studies suggest that ayahuasca may have beneficial effects on various physical and psychological conditions, namely in the treatment of depression, anxiety and various diseases of the neurobiological system, as well as anti-inflammatory and antimicrobial properties, demonstrating its therapeutic potential. The number of studies that address this issue has also been growing, demonstrating interest in the search for alternative treatments. However, to the best of our knowledge, this is the first systematic review where all the findings of therapeutic effects associated with the consumption of ayahuasca are reviewed.
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Affiliation(s)
- Joana Gonçalves
- Centro de Investigação em Ciências da Saúde (CICS-UBI), Universidade da Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
- Laboratório de Fármaco-Toxicologia, UBIMedical, Universidade da Beira Interior, Estrada Municipal 506, 6200-284 Covilhã, Portugal
| | - Ângelo Luís
- Centro de Investigação em Ciências da Saúde (CICS-UBI), Universidade da Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
- Laboratório de Fármaco-Toxicologia, UBIMedical, Universidade da Beira Interior, Estrada Municipal 506, 6200-284 Covilhã, Portugal
| | - Eugenia Gallardo
- Centro de Investigação em Ciências da Saúde (CICS-UBI), Universidade da Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
- Laboratório de Fármaco-Toxicologia, UBIMedical, Universidade da Beira Interior, Estrada Municipal 506, 6200-284 Covilhã, Portugal
| | - Ana Paula Duarte
- Centro de Investigação em Ciências da Saúde (CICS-UBI), Universidade da Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
- Laboratório de Fármaco-Toxicologia, UBIMedical, Universidade da Beira Interior, Estrada Municipal 506, 6200-284 Covilhã, Portugal
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Costa MÂ. A Dose of Creativity: An Integrative Review of the Effects of Serotonergic Psychedelics on Creativity. J Psychoactive Drugs 2022:1-11. [PMID: 35895868 DOI: 10.1080/02791072.2022.2106805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
This integrative review was conducted to summarize the knowledge pertaining to the effects that serotonergic psychedelics can have on creativity, a multi-dimensional construct referring to the ability to produce original and valuable artifacts. Psychedelics, which have long been hailed as substances that can enhance the creative process in their users, have experienced a recent resurgence in research, allowing the opportunity to better understand this relationship. To this end, I reviewed literature which attempted to study the effects of serotonergic psychedelics on creativity through psychometric methods. A total of eleven studies were reviewed, with four psychedelic compounds represented. Every study assessed components and subcomponents of divergent and convergent thinking, with only one instance of product assessment. Results suggest that convergent thinking may increase during the post-acute phases of the drugs' intake, fostering the capacity for development of previously generated ideas. However, this evidence may be circumstantial based on the low number of studies available, small sample sizes, overall lack of randomized controlled trials, and significant methodological limitations throughout most studies. Potential mechanisms underlying these effects are discussed, along with the current state of the research and implications for future studies.
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Affiliation(s)
- Miguel Ângelo Costa
- Instituto de Ciências da Saúde, Universidade Católica Portuguesa, Lisbon, Portugal
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3
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McGovern HT, Leptourgos P, Hutchinson BT, Corlett PR. Do psychedelics change beliefs? Psychopharmacology (Berl) 2022; 239:1809-1821. [PMID: 35507071 DOI: 10.1007/s00213-022-06153-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 04/19/2022] [Indexed: 01/29/2023]
Abstract
Renewed interest in psychedelics has reignited the debate about whether and how they change human beliefs. In both the clinical and social-cognitive domains, psychedelic consumption may be accompanied by profound, and sometimes lasting, belief changes. We review these changes and their possible underlying mechanisms. Rather than inducing de novo beliefs, we argue psychedelics may instead change the impact of affect and of others' suggestions on how beliefs are imputed. Critically, we find that baseline beliefs (in the possible effects of psychedelics, for example) might color the acute effects of psychedelics as well as longer-term changes. If we are to harness the apparent potential of psychedelics in the clinic and for human flourishing more generally, these possibilities must be addressed empirically.
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Affiliation(s)
- H T McGovern
- School of Psychology, The University of Queensland, Brisbane, QLD, Australia
| | - P Leptourgos
- Department of Psychiatry, Yale University, New Haven, CT, USA
| | - B T Hutchinson
- Research School of Psychology, The Australian National University, Canberra, ACT, Australia
| | - P R Corlett
- Department of Psychiatry, Yale University, New Haven, CT, USA.
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Carter O, van Swinderen B, Leopold DA, Collin S, Maier A. Perceptual rivalry across animal species. J Comp Neurol 2020; 528:3123-3133. [PMID: 32361986 PMCID: PMC7541519 DOI: 10.1002/cne.24939] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 04/18/2020] [Accepted: 04/20/2020] [Indexed: 01/10/2023]
Abstract
This review in memoriam of Jack Pettigrew provides an overview of past and current research into the phenomenon of multistable perception across multiple animal species. Multistable perception is characterized by two or more perceptual interpretations spontaneously alternating, or rivaling, when animals are exposed to stimuli with inherent sensory ambiguity. There is a wide array of ambiguous stimuli across sensory modalities, ranging from the configural changes observed in simple line drawings, such as the famous Necker cube, to the alternating perception of entire visual scenes that can be instigated by interocular conflict. The latter phenomenon, called binocular rivalry, in particular caught the attention of the late Jack Pettigrew, who combined his interest in the neuronal basis of perception with a unique comparative biological approach that considered ambiguous sensation as a fundamental problem of sensory systems that has shaped the brain throughout evolution. Here, we examine the research findings on visual perceptual alternation and suppression in a wide variety of species including insects, fish, reptiles, and primates. We highlight several interesting commonalities across species and behavioral indicators of perceptual alternation. In addition, we show how the comparative approach provides new avenues for understanding how the brain suppresses opposing sensory signals and generates alternations in perceptual dominance.
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Affiliation(s)
- Olivia Carter
- Melbourne School of Psychological Sciences, University of Melbourne, Parkville, VIC, AUS
| | | | | | - Shaun Collin
- School of Life Sciences, La Trobe University, Melbourne, VIC, AUS
| | - Alex Maier
- Department of Psychology, Vanderbilt University, Nashville, TN, USA
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Estrella-Parra EA, Almanza-Pérez JC, Alarcón-Aguilar FJ. Ayahuasca: Uses, Phytochemical and Biological Activities. NATURAL PRODUCTS AND BIOPROSPECTING 2019; 9:251-265. [PMID: 31134518 PMCID: PMC6646606 DOI: 10.1007/s13659-019-0210-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 05/12/2019] [Indexed: 05/14/2023]
Abstract
Ayahuasca (caapi, yajé), is a psychoactive brew from the Amazon Basin region of South America traditionally considered a "master plant." It is prepared as a decoction from Banisteriopsis caapi and Psychotria viridis, which it is thought that it stimulates creative thinking and visual creativity. Native healers of the Orinoco and Amazon basins have used traditionally ayahuasca as a healing tool for multiple purposes, particularly to treat psychological disorders in the patients, with some beneficial effects experimentally and clinically validated. Recently, several syncretic religions, as the "União de Vegetal" (UDV) group in Brazil, have been spread around the world. The use of ayahuasca has been popularized by internet and smart-shops, bringing the psychoactive substance to new highs, emerging new "ayahuasqueros." Ayahuasca has alkaloids as β-carbolines and dimethyltryptamines, which inhibit the monoamine oxidase and active the 5-HT2A (5-hydroxytryptamine) receptor, respectively, resulting in hallucinations in the users. Ayahuasca induces a psychedelic change in the anteroposterior coupling of the electrophysiological brain oscillations in humans. Traditional ayahuasca beverage is generating pharmacological, commercial and spiritual interest among the scientific community, government people, and different populations worldwide. The goal of this article is to report about the uses, chemistry and biological activities of ayahuasca.
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Affiliation(s)
- Edgar Antonio Estrella-Parra
- Laboratorio de Farmacología. Dpto. Ciencias de la Salud. Div. C.B.S. Universidad Autónoma Metropolitana, Unidad Iztapalapa. Av. San Rafael Atlixco No. 186, Col. Vicentina, 09340, Mexico CDMX, Mexico
- Laboratorio de Fitoquímica, Laboratorio de Farmacognosia, Laboratorio de Fisiología Vegetal, Unidad UBIPRO, FES-Iztacala, UNAM, Tlalnepantla de Baz, 54090, Mexico CDMX, Mexico
| | - Julio Cesar Almanza-Pérez
- Laboratorio de Farmacología. Dpto. Ciencias de la Salud. Div. C.B.S. Universidad Autónoma Metropolitana, Unidad Iztapalapa. Av. San Rafael Atlixco No. 186, Col. Vicentina, 09340, Mexico CDMX, Mexico
| | - Francisco Javier Alarcón-Aguilar
- Laboratorio de Farmacología. Dpto. Ciencias de la Salud. Div. C.B.S. Universidad Autónoma Metropolitana, Unidad Iztapalapa. Av. San Rafael Atlixco No. 186, Col. Vicentina, 09340, Mexico CDMX, Mexico.
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Abstract
How do psychedelic drugs produce their characteristic range of acute effects in perception, emotion, cognition, and sense of self? How do these effects relate to the clinical efficacy of psychedelic-assisted therapies? Efforts to understand psychedelic phenomena date back more than a century in Western science. In this article I review theories of psychedelic drug effects and highlight key concepts which have endured over the last 125 years of psychedelic science. First, I describe the subjective phenomenology of acute psychedelic effects using the best available data. Next, I review late 19th-century and early 20th-century theories-model psychoses theory, filtration theory, and psychoanalytic theory-and highlight their shared features. I then briefly review recent findings on the neuropharmacology and neurophysiology of psychedelic drugs in humans. Finally, I describe recent theories of psychedelic drug effects which leverage 21st-century cognitive neuroscience frameworks-entropic brain theory, integrated information theory, and predictive processing-and point out key shared features that link back to earlier theories. I identify an abstract principle which cuts across many theories past and present: psychedelic drugs perturb universal brain processes that normally serve to constrain neural systems central to perception, emotion, cognition, and sense of self. I conclude that making an explicit effort to investigate the principles and mechanisms of psychedelic drug effects is a uniquely powerful way to iteratively develop and test unifying theories of brain function.
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Affiliation(s)
- Link R. Swanson
- Center for Cognitive Sciences, University of Minnesota, Minneapolis, MN, United States
- Department of Philosophy, University of Minnesota, Minneapolis, MN, United States
- Minnesota Center for Philosophy of Science, University of Minnesota, Minneapolis, MN, United States
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Dos Santos RG, Balthazar FM, Bouso JC, Hallak JE. The current state of research on ayahuasca: A systematic review of human studies assessing psychiatric symptoms, neuropsychological functioning, and neuroimaging. J Psychopharmacol 2016; 30:1230-1247. [PMID: 27287824 DOI: 10.1177/0269881116652578] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
RATIONALE In recent decades, the use of ayahuasca (AYA) - a β-carboline- and dimethyltryptamine-rich hallucinogenic botanical preparation traditionally used by Northwestern Amazonian tribes for ritual and therapeutic purposes - has spread from South America to Europe and the USA, raising concerns about its possible toxicity and hopes of its therapeutic potential. Thus, it is important to analyze the acute, subacute, and long-term effects of AYA to assess its safety and toxicity. OBJECTIVES The purpose of this study was to conduct a systematic review of human studies assessing AYA effects on psychiatric symptoms, neuropsychological functioning, and neuroimaging. METHODS Papers published until 16 December 2015 were included from PubMed, LILACS and SciELO databases following a comprehensive search strategy and pre-determined set of criteria for article selection. RESULTS The review included 28 full-text articles. Acute AYA administration was well tolerated, increased introspection and positive mood, altered visual perceptions, activated frontal and paralimbic regions and decreased default mode network activity. It also improved planning and inhibitory control and impaired working memory, and showed antidepressive and antiaddictive potentials. Long-term AYA use was associated with increased cortical thickness of the anterior cingulate cortex and cortical thinning of the posterior cingulate cortex, which was inversely correlated to age of onset, intensity of prior AYA use, and spirituality. Subacute and long-term AYA use was not associated with increased psychopathology or cognitive deficits, being associated with enhanced mood and cognition, increased spirituality, and reduced impulsivity. CONCLUSIONS Acute, subacute, and long-term AYA use seems to have low toxicity. Preliminary studies about potential therapeutic effects of AYA need replication due to their methodological limitations.
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Affiliation(s)
- Rafael G Dos Santos
- Department of Neurosciences and Behavior, University of São Paulo, Ribeirão Preto, Brazil .,International Center for Ethnobotanical Education, Research and Service, Barcelona, Spain
| | - Fermanda M Balthazar
- Federal Institute of Education, Science and Technology of São Paulo, São Paulo, Brazil
| | - José C Bouso
- International Center for Ethnobotanical Education, Research and Service, Barcelona, Spain
| | - Jaime Ec Hallak
- Department of Neurosciences and Behavior, University of São Paulo, Ribeirão Preto, Brazil.,National Institute of Science and Technology - Translational Medicine, Ribeirão Preto, Brazil
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Abstract
Psychedelics (serotonergic hallucinogens) are powerful psychoactive substances that alter perception and mood and affect numerous cognitive processes. They are generally considered physiologically safe and do not lead to dependence or addiction. Their origin predates written history, and they were employed by early cultures in many sociocultural and ritual contexts. After the virtually contemporaneous discovery of (5R,8R)-(+)-lysergic acid-N,N-diethylamide (LSD)-25 and the identification of serotonin in the brain, early research focused intensively on the possibility that LSD and other psychedelics had a serotonergic basis for their action. Today there is a consensus that psychedelics are agonists or partial agonists at brain serotonin 5-hydroxytryptamine 2A receptors, with particular importance on those expressed on apical dendrites of neocortical pyramidal cells in layer V. Several useful rodent models have been developed over the years to help unravel the neurochemical correlates of serotonin 5-hydroxytryptamine 2A receptor activation in the brain, and a variety of imaging techniques have been employed to identify key brain areas that are directly affected by psychedelics. Recent and exciting developments in the field have occurred in clinical research, where several double-blind placebo-controlled phase 2 studies of psilocybin-assisted psychotherapy in patients with cancer-related psychosocial distress have demonstrated unprecedented positive relief of anxiety and depression. Two small pilot studies of psilocybin-assisted psychotherapy also have shown positive benefit in treating both alcohol and nicotine addiction. Recently, blood oxygen level-dependent functional magnetic resonance imaging and magnetoencephalography have been employed for in vivo brain imaging in humans after administration of a psychedelic, and results indicate that intravenously administered psilocybin and LSD produce decreases in oscillatory power in areas of the brain's default mode network.
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Affiliation(s)
- David E Nichols
- Eschelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina
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Frecska E, Bokor P, Winkelman M. The Therapeutic Potentials of Ayahuasca: Possible Effects against Various Diseases of Civilization. Front Pharmacol 2016; 7:35. [PMID: 26973523 PMCID: PMC4773875 DOI: 10.3389/fphar.2016.00035] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 02/08/2016] [Indexed: 11/23/2022] Open
Abstract
Ayahuasca is an Amazonian psychoactive brew of two main components. Its active agents are β-carboline and tryptamine derivatives. As a sacrament, ayahuasca is still a central element of many healing ceremonies in the Amazon Basin and its ritual consumption has become common among the mestizo populations of South America. Ayahuasca use amongst the indigenous people of the Amazon is a form of traditional medicine and cultural psychiatry. During the last two decades, the substance has become increasingly known among both scientists and laymen, and currently its use is spreading all over in the Western world. In the present paper we describe the chief characteristics of ayahuasca, discuss important questions raised about its use, and provide an overview of the scientific research supporting its potential therapeutic benefits. A growing number of studies indicate that the psychotherapeutic potential of ayahuasca is based mostly on the strong serotonergic effects, whereas the sigma-1 receptor (Sig-1R) agonist effect of its active ingredient dimethyltryptamine raises the possibility that the ethnomedical observations on the diversity of treated conditions can be scientifically verified. Moreover, in the right therapeutic or ritual setting with proper preparation and mindset of the user, followed by subsequent integration of the experience, ayahuasca has proven effective in the treatment of substance dependence. This article has two important take-home messages: (1) the therapeutic effects of ayahuasca are best understood from a bio-psycho-socio-spiritual model, and (2) on the biological level ayahuasca may act against chronic low grade inflammation and oxidative stress via the Sig-1R which can explain its widespread therapeutic indications.
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Affiliation(s)
- Ede Frecska
- Department of Psychiatry, Faculty of Medicine, University of Debrecen Debrecen, Hungary
| | - Petra Bokor
- Doctoral School of Psychology, University of Pécs Pécs, Hungary
| | - Michael Winkelman
- School of Human Evolution and Social Change, Arizona State University, Tempe AZ, USA
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Jia T, Ye X, Wei Q, Xie W, Cai C, Mu J, Dong Y, Hu P, Hu X, Tian Y, Wang K. Difference in the binocular rivalry rate between depressive episodes and remission. Physiol Behav 2015; 151:272-8. [DOI: 10.1016/j.physbeh.2015.08.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 07/31/2015] [Accepted: 08/01/2015] [Indexed: 10/23/2022]
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Acute effects of ayahuasca on neuropsychological performance: differences in executive function between experienced and occasional users. Psychopharmacology (Berl) 2013; 230:415-24. [PMID: 23793226 DOI: 10.1007/s00213-013-3167-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Accepted: 05/29/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND Ayahuasca, a South American psychotropic plant tea containing the psychedelic 5-HT2A receptor agonist N,N-dimethyltryptamine, has been shown to increase regional cerebral blood flow in prefrontal brain regions after acute administration to humans. Despite interactions at this level, neuropsychological studies have not found cognitive deficits in abstinent long-term users. OBJECTIVES Here, we wished to investigate the effects of acute ayahuasca intake on neuropsychological performance, specifically on working memory and executive function. METHODS Twenty-four ayahuasca users (11 long-term experienced users and 13 occasional users) were assessed in their habitual setting using the Stroop, Sternberg, and Tower of London tasks prior to and following ayahuasca intake. RESULTS Errors in the Sternberg task increased, whereas reaction times in the Stroop task decreased and accuracy was maintained for the whole sample following ayahuasca intake. Interestingly, results in the Tower of London showed significantly increased execution and resolution times and number of movements for the occasional but not the experienced users. Additionally, a correlation analysis including all subjects showed that impaired performance in the Tower of London was inversely correlated with lifetime ayahuasca use. CONCLUSIONS Acute ayahuasca administration impaired working memory but decreased stimulus-response interference. Interestingly, detrimental effects on higher cognition were only observed in the less experienced group. Rather than leading to increased impairment, greater prior exposure to ayahuasca was associated with reduced incapacitation. Compensatory or neuromodulatory effects associated with long-term ayahuasca intake could underlie preserved executive function in experienced users.
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Guimarães dos Santos R. Safety and Side Effects of Ayahuasca in Humans—An Overview Focusing on Developmental Toxicology. J Psychoactive Drugs 2013; 45:68-78. [DOI: 10.1080/02791072.2013.763564] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Frecska E, Móré CE, Vargha A, Luna LE. Enhancement of Creative Expression and Entoptic Phenomena as After-Effects of Repeated Ayahuasca Ceremonies. J Psychoactive Drugs 2012; 44:191-9. [DOI: 10.1080/02791072.2012.703099] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Salomon RM, Karageorgiou J, Dietrich MS, McLellan JY, Charboneau EJ, Blackford JU, Cowan RL. MDMA (Ecstasy) association with impaired fMRI BOLD thalamic coherence and functional connectivity. Drug Alcohol Depend 2012; 120:41-7. [PMID: 21807471 PMCID: PMC3224864 DOI: 10.1016/j.drugalcdep.2011.06.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/25/2010] [Revised: 05/19/2011] [Accepted: 06/22/2011] [Indexed: 12/31/2022]
Abstract
BACKGROUND MDMA exposure is associated with chronic serotonergic dysfunction in preclinical and clinical studies. A recent functional magnetic resonance imaging (fMRI) comparison of past MDMA users to non-MDMA-using controls revealed increased spatial extent and amplitude of activation in the supplementary motor area during motor tasks (Karageorgiou et al., 2009). Blood oxygenation level dependent (BOLD) data from that study were reanalyzed for intraregional coherence and for inter-regional temporal correlations between time series, as functional connectivity. METHODS Fourteen MDMA users and ten controls reporting similar non-MDMA abuse performed finger taps during fMRI. Fourteen motor pathway regions plus a pontine raphé region were examined. Coherence was expressed as percent of voxels positively correlated with an intraregional index voxel. Functional connectivity was determined using wavelet correlations. RESULTS Intraregional thalamic coherence was significantly diminished at low frequencies in MDMA users compared to controls (p=0.009). Inter-regional functional connectivity was significantly weaker for right thalamo - left caudate (p=0.002), right thalamo - left thalamus (p=0.007), right caudate - right postcentral (p=0.007) and right supplementary motor area - right precentral gyrus (p=0.011) region pairs compared to controls. When stratified by lifetime exposure, significant negative associations were observed between cumulative MDMA use and functional connectivity in seven other region-pairs, while only one region-pair showed a positive association. CONCLUSIONS Reported prior MDMA use was associated with deficits in BOLD intraregional coherence and inter-regional functional connectivity, even among functionally robust pathways involving motor regions. This suggests that MDMA use is associated with long-lasting effects on brain neurophysiology beyond the cognitive domain.
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Affiliation(s)
- Ronald M Salomon
- Psychiatric Neuroimaging Program, Vanderbilt University School of Medicine, Nashville, TN 37212, USA.
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15
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Nagamine M, Yoshino A, Miyazaki M, Takahashi Y, Nomura S. Difference in binocular rivalry rate between patients with bipolar I and bipolar II disorders. Bipolar Disord 2009; 11:539-46. [PMID: 19624393 DOI: 10.1111/j.1399-5618.2009.00719.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE When dissimilar figures are presented to each eye individually, perception alternates spontaneously between each monocular view. This phenomenon, known as binocular rivalry, has been used as a powerful tool to investigate conscious visual awareness. Of clinical relevance, Pettigrew and Miller (Proc Biol Sci 1998; 265: 2141-2148) found slow perceptual alternation rates in patients with bipolar I disorder (BD-I). For a better understanding of differences between BD-I and bipolar II disorder (BD-II), we examined whether perceptual alternation rates of binocular rivalry differ between the two subtypes of bipolar disorder. METHODS The subjects comprised 25 healthy controls, 11 patients with BD-I, and 17 patients with BD-II. They underwent binocular rivalry examination. One-way analysis of variance was conducted to determine differences in the phase duration of binocular rivalry between the control, BD-I, and BD-II groups. RESULTS Significant differences were observed in the mean phase duration of binocular rivalry between the groups. Although the medication administered did not differ significantly between the BD-I and BD-II patients, the phase duration was significantly longer among the BD-I patients than the BD-II patients and controls, whereas no significant difference was observed in the phase duration between the BD-II patients and controls. CONCLUSION The present results reveal a significant difference in the mean phase duration of binocular rivalry between subjects with BD-I and those with BD-II, suggesting the presence of some neurobiological difference between these two subtypes of bipolar disorder.
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Affiliation(s)
- Masanori Nagamine
- Department of Psychiatry, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan
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16
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Baker DH, Graf EW. On the relation between dichoptic masking and binocular rivalry. Vision Res 2009; 49:451-9. [DOI: 10.1016/j.visres.2008.12.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2008] [Revised: 12/05/2008] [Accepted: 12/05/2008] [Indexed: 11/16/2022]
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Effects of selective 5-HT1A agonist tandospirone on the rate and rhythmicity of binocular rivalry. Psychopharmacology (Berl) 2008; 198:279-86. [PMID: 18408919 DOI: 10.1007/s00213-008-1139-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2007] [Accepted: 03/03/2008] [Indexed: 10/22/2022]
Abstract
RATIONALE When dissimilar figures are presented to each eye individually, perception alternates spontaneously between each monocular view. This phenomenon, binocular rivalry, has been suggested to depend on serotonergic neural systems. OBJECTIVE To investigate the relationship between binocular rivalry and serotonergic neural systems in more detail, we measured the perceptual alternation rate and rhythmicity of binocular rivalry under the influence of the 5-HT(1A) agonist tandospirone. MATERIALS AND METHODS Fifteen healthy volunteers were tested under placebo and 60 mg tandospirone conditions using the single-blind method. The perceptual alternation rate and rhythmicity of binocular rivalry were measured at pre-administration and at 90, 180, and 360 min post-administration. RESULTS Compared to placebo, the administration of tandospirone decreased the rate and rhythmicity of perceptual switching significantly at 90 and 180 min post-administration in a manner that is consistent with its pharmacokinetics. CONCLUSIONS The present results suggest that the 5-HT(1A) neural pathways, mainly located in the mesolimbic system and brainstem, may play a crucial role as an oscillator in perceptual rivalry alternations.
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Carter OL, Hasler F, Pettigrew JD, Wallis GM, Liu GB, Vollenweider FX. Psilocybin links binocular rivalry switch rate to attention and subjective arousal levels in humans. Psychopharmacology (Berl) 2007; 195:415-24. [PMID: 17874073 DOI: 10.1007/s00213-007-0930-9] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2006] [Accepted: 08/24/2007] [Indexed: 11/26/2022]
Abstract
RATIONALE Binocular rivalry occurs when different images are simultaneously presented to each eye. During continual viewing of this stimulus, the observer will experience repeated switches between visual awareness of the two images. Previous studies have suggested that a slow rate of perceptual switching may be associated with clinical and drug-induced psychosis. OBJECTIVES The objective of the study was to explore the proposed relationship between binocular rivalry switch rate and subjective changes in psychological state associated with 5-HT2A receptor activation. MATERIALS AND METHODS This study used psilocybin, the hallucinogen found naturally in Psilocybe mushrooms that had previously been found to induce psychosis-like symptoms via the 5-HT2A receptor. The effects of psilocybin (215 microg/kg) were considered alone and after pretreatment with the selective 5-HT2A antagonist ketanserin (50 mg) in ten healthy human subjects. RESULTS Psilocybin significantly reduced the rate of binocular rivalry switching and increased the proportion of transitional/mixed percept experience. Pretreatment with ketanserin blocked the majority of psilocybin's "positive" psychosis-like hallucinogenic symptoms. However, ketanserin had no influence on either the psilocybin-induced slowing of binocular rivalry or the drug's "negative-type symptoms" associated with reduced arousal and vigilance. CONCLUSIONS Together, these findings link changes in binocular rivalry switching rate to subjective levels of arousal and attention. In addition, it suggests that psilocybin's effect on binocular rivalry is unlikely to be mediated by the 5-HT2A receptor.
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Affiliation(s)
- Olivia L Carter
- Vision Touch and Hearing Research Center, School of Biomedical Science, University of Queensland, Brisbane, Australia.
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Santos RG, Landeira-Fernandez J, Strassman RJ, Motta V, Cruz APM. Effects of ayahuasca on psychometric measures of anxiety, panic-like and hopelessness in Santo Daime members. JOURNAL OF ETHNOPHARMACOLOGY 2007; 112:507-13. [PMID: 17532158 DOI: 10.1016/j.jep.2007.04.012] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Revised: 04/16/2007] [Accepted: 04/18/2007] [Indexed: 05/15/2023]
Abstract
The use of the hallucinogenic brew ayahuasca, obtained from infusing the shredded stalk of the malpighiaceous plant Banisteriopsis caapi with the leaves of other plants such as Psychotria viridis, is growing in urban centers of Europe, South and North America in the last several decades. Despite this diffusion, little is known about its effects on emotional states. The present study investigated the effects of ayahuasca on psychometric measures of anxiety, panic-like and hopelessness in members of the Santo Daime, an ayahuasca-using religion. Standard questionnaires were used to evaluate state-anxiety (STAI-state), trait-anxiety (STAI-trait), panic-like (ASI-R) and hopelessness (BHS) in participants that ingested ayahuasca for at least 10 consecutive years. The study was done in the Santo Daime church, where the questionnaires were administered 1h after the ingestion of the brew, in a double-blind, placebo-controlled procedure. While under the acute effects of ayahuasca, participants scored lower on the scales for panic and hopelessness related states. Ayahuasca ingestion did not modify state- or trait-anxiety. The results are discussed in terms of the possible use of ayahuasca in alleviating signs of hopelessness and panic-like related symptoms.
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Affiliation(s)
- R G Santos
- Departamento de Processos Psicológicos Básicos, Instituto de Psicologia, Universidade de Brasília, Asa Norte, Brasília-DF 70910-900, Brazil.
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Santos RGD, Moraes CCD, Holanda A. Ayahuasca e redução do uso abusivo de psicoativos: eficácia terapêutica? PSICOLOGIA: TEORIA E PESQUISA 2006. [DOI: 10.1590/s0102-37722006000300014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Trata-se de uma avaliação do possível papel do uso da ayahuasca, em contexto religioso, como auxiliar na redução do consumo abusivo de psicoativos, a partir de uma pesquisa de estudo de caso. Foi realizada uma entrevista aberta com uma usuária regular de cocaína, nicotina e álcool que abandonou este comportamento após entrar em contato com a ayahuasca num contexto ritualizado. O caso foi analisado à luz da comparação deste com a literatura existente sobre o assunto. Foi traçada uma relação entre o início do uso da ayahuasca e o abandono do uso de cocaína, nicotina e álcool pela entrevistada, a partir da avaliação das representações simbólicas e das descrições de suas primeiras experiências com a bebida.
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Kolp E, Friedman HL, Young MS, Krupitsky E. Ketamine Enhanced Psychotherapy: Preliminary Clinical Observations on Its Effectiveness in Treating Alcoholism. ACTA ACUST UNITED AC 2006. [DOI: 10.1207/s15473333thp3404_7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Carter OL, Pettigrew JD, Hasler F, Wallis GM, Liu GB, Hell D, Vollenweider FX. Modulating the rate and rhythmicity of perceptual rivalry alternations with the mixed 5-HT2A and 5-HT1A agonist psilocybin. Neuropsychopharmacology 2005; 30:1154-62. [PMID: 15688092 DOI: 10.1038/sj.npp.1300621] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Binocular rivalry occurs when different images are presented simultaneously to corresponding points within the left and right eyes. Under these conditions, the observer's perception will alternate between the two perceptual alternatives. Motivated by the reported link between the rate of perceptual alternations, symptoms of psychosis and an incidental observation that the rhythmicity of perceptual alternations during binocular rivalry was greatly increased 10 h after the consumption of LSD, this study aimed to investigate the pharmacology underlying binocular rivalry and to explore the connection between the timing of perceptual switching and psychosis. Psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine, PY) was chosen for the study because, like LSD, it is known to act as an agonist at serotonin (5-HT)1A and 5-HT2A receptors and to produce an altered state sometimes marked by psychosis-like symptoms. A total of 12 healthy human volunteers were tested under placebo, low-dose (115 microg/kg) and high-dose (250 microg/kg) PY conditions. In line with predictions, under both low- and high-dose conditions, the results show that at 90 min postadministration (the peak of drug action), rate and rhythmicity of perceptual alternations were significantly reduced from placebo levels. Following the 90 min testing period, the perceptual switch rate successively increased, with some individuals showing increases well beyond pretest levels at the final testing, 360 min postadministration. However, as some subjects had still not returned to pretest levels by this time, the mean phase duration at 360 min was not found to differ significantly from placebo. Reflecting the drug-induced changes in rivalry phase durations, subjects showed clear changes in psychological state as indexed by the 5D-ASC (altered states of consciousness) rating scales. This study suggests the involvement of serotonergic pathways in binocular rivalry and supports the previously proposed role of a brainstem oscillator in perceptual rivalry alternations and symptoms of psychosis.
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Affiliation(s)
- Olivia L Carter
- Vision Touch and Hearing Research Center, School of Biomedical Science, University of Queensland, Australia.
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