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Yang KH, Satybaldiyeva N, Allen MR, Ayers JW, Leas EC. State Cannabis and Psychedelic Legislation and Microdosing Interest in the US. JAMA HEALTH FORUM 2024; 5:e241653. [PMID: 38941086 PMCID: PMC11214114 DOI: 10.1001/jamahealthforum.2024.1653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 04/25/2024] [Indexed: 06/29/2024] Open
Abstract
Importance Despite growing interest in psychedelics, there is a lack of routine population-based surveillance of psychedelic microdosing (taking "subperceptual" doses of psychedelics, approximately one-twentieth to one-fifth of a full dose, over prolonged periods). Analyzing Google search queries can provide insights into public interest and help address this gap. Objective To analyze trends in public interest in microdosing in the US through Google search queries and assess their association with cannabis and psychedelic legislative reforms. Design, Setting, and Participants In this cross-sectional study, a dynamic event-time difference-in-difference time series analysis was used to assess the impact of cannabis and psychedelic legislation on microdosing search rates from January 1, 2010, to December 31, 2023. Google search rates mentioning "microdosing," "micro dosing," "microdose," or "micro dose" within the US and across US states were measured in aggregate. Exposure Enactment of (1) local psychedelic decriminalization laws; (2) legalization of psychedelic-assisted therapy and statewide psychedelic decriminalization; (3) statewide medical cannabis use laws; (4) statewide recreational cannabis use laws; and (5) all cannabis and psychedelic use restricted. Main Outcome and Measures Microdosing searches per 10 million Google queries were measured, examining annual and monthly changes in search rates across the US, including frequency and nature of related searches. Results Searches for microdosing in the US remained stable until 2014, then increased annually thereafter, with a cumulative increase by a factor of 13.4 from 2015 to 2023 (7.9 per 10 million to 105.6 per 10 million searches, respectively). In 2023, there were 3.0 million microdosing searches in the US. Analysis at the state level revealed that local psychedelic decriminalization laws were associated with an increase in search rates by 22.4 per 10 million (95% CI, 7.5-37.2), statewide psychedelic therapeutic legalization and decriminalization were associated with an increase in search rates by 28.9 per 10 million (95% CI, 16.5-41.2), statewide recreational cannabis laws were associated with an increase in search rates by 40.9 per 10 million (95% CI, 28.6-53.3), and statewide medical cannabis laws were associated with an increase in search rates by 11.5 per 10 million (95% CI, 6.0-16.9). From August through December 2023, 27.0% of the variation in monthly microdosing search rates between states was explained by differences in cannabis and psychedelics legal status. Conclusion and Relevance This cross-sectional study found that state-led legislative reforms on cannabis and psychedelics were associated with increased public interest in microdosing psychedelics.
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Affiliation(s)
- Kevin H. Yang
- Department of Psychiatry, University of California San Diego School of Medicine, La Jolla
| | - Nora Satybaldiyeva
- Herbert Wertheim School of Public Health and Human Longevity Science, University of California San Diego, La Jolla
| | - Matthew R. Allen
- University of California San Diego School of Medicine, La Jolla
- Qualcomm Institute, University of California San Diego, La Jolla
| | - John W. Ayers
- Qualcomm Institute, University of California San Diego, La Jolla
- Altman Clinical Translational Research Institute, University of California San Diego, La Jolla
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, La Jolla
| | - Eric C. Leas
- Herbert Wertheim School of Public Health and Human Longevity Science, University of California San Diego, La Jolla
- Qualcomm Institute, University of California San Diego, La Jolla
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2
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Murphy RJ, Muthukumaraswamy S, de Wit H. Microdosing Psychedelics: Current Evidence From Controlled Studies. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2024; 9:500-511. [PMID: 38280630 DOI: 10.1016/j.bpsc.2024.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 01/06/2024] [Accepted: 01/09/2024] [Indexed: 01/29/2024]
Abstract
Taking regular low doses of psychedelic drugs (microdosing) is a practice that has drawn recent scientific and media attention for its potential psychotherapeutic effects. Yet, controlled studies evaluating this practice have lagged. Here, we review recent evidence focusing on studies that were conducted with rigorous experimental control. Studies conducted under laboratory settings using double-blind placebo-controlled procedures and investigator-supplied drug were compiled. The review includes demographic characteristics of participants and dependent measures such as physiological, behavioral, and subjective effects of the drugs. Review criteria were met by 14 studies, all of which involved acute or repeated low (5-20 μg) doses of lysergic acid diethylamide (LSD). Acute microdoses of LSD dose-dependently altered blood pressure, sleep, neural connectivity, social cognition, mood, and perception of pain and time. Perceptible drug effects were reported at doses of 10 to 20 μg but not 5 μg. No serious adverse effects were reported. Repeated doses of LSD did not alter mood or cognition on any of the measures studied. The findings suggest that low doses of LSD are safe and produce acute behavioral and neural effects in healthy adults. Further studies are warranted to extend these findings to patient samples and to other psychedelic drugs and to investigate microdosing as a potential pharmacological treatment for psychiatric disorders.
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Affiliation(s)
- Robin J Murphy
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
| | - Suresh Muthukumaraswamy
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Harriet de Wit
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, Illinois
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3
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Pop I, Dinkelacker J. Unlocking the self: Can microdosing psychedelics make one feel more authentic? NORDIC STUDIES ON ALCOHOL AND DRUGS 2024; 41:142-155. [PMID: 38645971 PMCID: PMC11027848 DOI: 10.1177/14550725231175353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 04/26/2023] [Indexed: 04/23/2024] Open
Abstract
Background and aim: In the present study, we focus on the relationship between state authenticity - the experience of being true to oneself in a particular moment - and microdosing - a practice that implies repeatedly ingesting very small doses of psychedelics that do not reach the threshold for perceptual alterations. We propose that microdosing could increase state authenticity through influencing people's mood and the number and satisfaction with daily activities. Methods: We used self-assessments of state authenticity collected from 18 microdosers in the Netherlands across the period of 1 month for a total of 192 observations. Results: We found that on the microdosing day and the day thereafter, state authenticity was significantly higher. Furthermore, the number of activities and the satisfaction with them were higher on the day when participants microdosed, while the following day only the number of activities was higher. Both the number or activities and the satisfaction with them were positively related to state authenticity. Conclusion: We propose that feeling and behaving authentically could have a central role in explaining the positive effects of microdosing on health and wellbeing that are reported by current research.
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Affiliation(s)
- Ioana Pop
- Tilburg University, Sociology Department, Tilburg, The Netherlands
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Pop IA, Gielens E, Kottmann H, Achterberg P. Exploring the discourses around microdosing psychedelics within the r/microdosing online community. Soc Sci Med 2024; 347:116702. [PMID: 38520826 DOI: 10.1016/j.socscimed.2024.116702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 02/13/2024] [Accepted: 02/15/2024] [Indexed: 03/25/2024]
Abstract
In the present contribution, we examine the practice of microdosing psychedelics (microdosing) through textual analysis of the content produced by a dedicated online community, the r/microdosing subreddit. We collected a comprehensive dataset of publicly available submissions from this community and used structural topic modelling to identify and analyse the prevalent topics within the discussions. Through our analysis, we identified 16 distinct topics that mapped into clinical, human enhancement, as well as self-medication narratives. Notably, we found that the majority of discussions revolved around "how to" topics, supporting our argument that such online communities serve as essential information hubs, facilitating the dissemination of practical knowledge related to microdosing practices among the general population. The identified impact of the Covid-19 pandemic on the prevalence of discussion topics suggests that individuals within the online community may perceive microdosing primarily as a means of self-medication during times of heightened stress and uncertainty. Our findings contribute to the field of health sociology and psychedelic research by shedding light on the sociocultural factors influencing healthcare practices, including the role of online communities in facilitating processes of self-medicalization and self-medication.
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Affiliation(s)
- Ioana Andreea Pop
- Tilburg University, Sociology Department, PO BOX 90153, 5000 LE, Tilburg, the Netherlands.
| | - Erwin Gielens
- Tilburg University, Sociology Department, PO BOX 90153, 5000 LE, Tilburg, the Netherlands.
| | - Hannah Kottmann
- Tilburg University, Sociology Department, PO BOX 90153, 5000 LE, Tilburg, the Netherlands.
| | - Peter Achterberg
- Tilburg University, Sociology Department, PO BOX 90153, 5000 LE, Tilburg, the Netherlands.
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Petranker R, Anderson T, Fewster EC, Aberman Y, Hazan M, Gaffrey M, Seli P. Keeping the promise: a critique of the current state of microdosing research. Front Psychiatry 2024; 15:1217102. [PMID: 38374976 PMCID: PMC10875010 DOI: 10.3389/fpsyt.2024.1217102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 01/05/2024] [Indexed: 02/21/2024] Open
Abstract
Introduction The practice of taking small, sub-hallucinogenic doses of psychedelics, known as microdosing, has exploded in popularity over the last decade. Users claim benefits ranging from improved mood and enhanced creativity to an increased sense of meaning and connectedness in life. While research on microdosing is still lagging behind the shift in public opinion, several papers have been published in the last five years which attempted to assess the effects of microdosing. Methods This review paper aimed to critically analyze the research practices used in the recent wave of microdosing research: We reviewed 15 papers published before the closing date of this review in March 2022. Results Our review concludes that it is premature to draw any conclusions about the efficacy or safety of microdosing since the research quality cannot be considered confirmatory. Discussion We propose some potential causes for the current state of the literature and some suggestions for how these causes may be ameliorated.
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Affiliation(s)
- Rotem Petranker
- Department of Psychology, Neuroscience and Behaviour, Hamilton, ON, Canada
| | - Thomas Anderson
- Department of Psychology, University of Toronto, Toronto, ON, Canada
| | | | | | - Marik Hazan
- Independent Researcher, New York, NY, United States
| | - Michael Gaffrey
- Department of Psychology and Neuroscience, Duke University, Durham, NC, United States
| | - Paul Seli
- Department of Psychology and Neuroscience, Duke University, Durham, NC, United States
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Madrid-Gambin F, Fabregat-Safont D, Gomez-Gomez A, Olesti E, Mason NL, Ramaekers JG, Pozo OJ. Present and future of metabolic and metabolomics studies focused on classical psychedelics in humans. Biomed Pharmacother 2023; 169:115775. [PMID: 37944438 DOI: 10.1016/j.biopha.2023.115775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 10/16/2023] [Accepted: 10/20/2023] [Indexed: 11/12/2023] Open
Abstract
Psychedelics are classical hallucinogen drugs that induce a marked altered state of consciousness. In recent years, there has been renewed attention to the possible use of classical psychedelics for the treatment of certain mental health disorders. However, further investigation to better understand their biological effects in humans, their mechanism of action, and their metabolism in humans is needed when considering the development of future novel therapeutic approaches. Both metabolic and metabolomics studies may help for these purposes. On one hand, metabolic studies aim to determine the main metabolites of the drug. On the other hand, the application of metabolomics in human psychedelics studies can help to further understand the biological processes underlying the psychedelic state and the mechanisms of action underlying their therapeutic potential. This review presents the state of the art of metabolic and metabolomic studies after lysergic acid diethylamide (LSD), mescaline, N,N-dimethyltryptamine (DMT) and β-carboline alkaloids (ayahuasca brew), 5-methoxy-DMT and psilocybin administrations in humans. We first describe the characteristics of the published research. Afterward, we reviewed the main results obtained by both metabolic and metabolomics (if available) studies in classical psychedelics and we found out that metabolic and metabolomics studies in psychedelics progress at two different speeds. Thus, whereas the main metabolites for classical psychedelics have been robustly established, the main metabolic alterations induced by psychedelics need to be explored. The integration of metabolomics and pharmacokinetics for investigating the molecular interaction between psychedelics and multiple targets may open new avenues in understanding the therapeutic role of psychedelics.
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Affiliation(s)
- Francisco Madrid-Gambin
- Applied Metabolomics Research Group, Hospital del Mar Research Institute, 08003 Barcelona, Spain.
| | - David Fabregat-Safont
- Applied Metabolomics Research Group, Hospital del Mar Research Institute, 08003 Barcelona, Spain; Environmental and Public Health Analytical Chemistry, Research Institute for Pesticides and Water, University Jaume I, 12071 Castelló, Spain
| | - Alex Gomez-Gomez
- Applied Metabolomics Research Group, Hospital del Mar Research Institute, 08003 Barcelona, Spain; CERBA Internacional, Chromatography Department, 08203 Sabadell, Spain
| | - Eulàlia Olesti
- Department of Clinical Pharmacology, Area Medicament, Hospital Clinic of Barcelona, 08036 Barcelona, Spain; Clinical Pharmacology, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain
| | - Natasha L Mason
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, 6200 MD Maastricht, the Netherlands
| | - Johannes G Ramaekers
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, 6200 MD Maastricht, the Netherlands
| | - Oscar J Pozo
- Applied Metabolomics Research Group, Hospital del Mar Research Institute, 08003 Barcelona, Spain.
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7
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Korman BA. The Rising Use of LSD among Business Managers. Subst Use Misuse 2023; 59:159-166. [PMID: 37822061 DOI: 10.1080/10826084.2023.2267105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/13/2023]
Abstract
BACKGROUND Although studies have demonstrated that the use of lysergic acid diethylamide (LSD) is on the rise in the United States, it remains unclear how this trend looks across the hierarchical ladder of the American workforce. This is relevant given that LSD is increasingly being touted as a means of boosting creativity and performance, with mounting anecdotal evidence that business managers in particular are turning to it for inspiration and insight. METHODS Using pooled cross-sectional data from the National Survey on Drug Use and Health (2006-2014) on 168,920 adults in the United States employed full-time (weighted = 117,270,940), this study investigates how temporal trends in past year LSD use differ among business managers and non-managers. RESULTS The results suggest that the prevalence of past year LSD use increased over time at a greater rate among business managers than non-managers and that this difference cannot be accounted for by changes in business managers' perceived risk of LSD use or general substance use relative to non-managers. CONCLUSIONS The study's findings indicate that temporal trends in past year LSD use depend on employees' hierarchical rank in their organization and suggest that business managers, regardless of gender, are becomingly increasingly interested in the potential competitive advantages that LSD may offer.
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Affiliation(s)
- Benjamin A Korman
- Chair of Organizational Behavior, University of Konstanz, Konstanz, Germany
- Cluster of Excellence "The Politics of Inequality", University of Konstanz, Konstanz, Germany
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Robinson GI, Li D, Wang B, Rahman T, Gerasymchuk M, Hudson D, Kovalchuk O, Kovalchuk I. Psilocybin and Eugenol Reduce Inflammation in Human 3D EpiIntestinal Tissue. Life (Basel) 2023; 13:2345. [PMID: 38137946 PMCID: PMC10744792 DOI: 10.3390/life13122345] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 12/09/2023] [Accepted: 12/13/2023] [Indexed: 12/24/2023] Open
Abstract
Inflammation plays a pivotal role in the development and progression of inflammatory bowel disease (IBD), by contributing to tissue damage and exacerbating the immune response. The investigation of serotonin receptor 2A (5-HT2A) ligands and transient receptor potential (TRP) channel ligands is of significant interest due to their potential to modulate key inflammatory pathways, mitigate the pathological effects of inflammation, and offer new avenues for therapeutic interventions in IBD. This study investigates the anti-inflammatory effects of 5-HT2A ligands, including psilocybin, 4-AcO-DMT, and ketanserin, in combination with TRP channel ligands, including capsaicin, curcumin, and eugenol, on the inflammatory response induced by tumor necrosis factor (TNF)-α and interferon (IFN)-γ in human 3D EpiIntestinal tissue. Enzyme-linked immunosorbent assay was used to assess the expression of pro-inflammatory markers TNF-α, IFN-γ, IL-6, IL-8, MCP-1, and GM-CSF. Our results show that psilocybin, 4-AcO-DMT, and eugenol significantly reduce TNF-α and IFN-γ levels, while capsaicin and curcumin decrease these markers to a lesser extent. Psilocybin effectively lowers IL-6 and IL-8 levels, but curcumin, capsaicin, and 4-AcO-DMT have limited effects on these markers. In addition, psilocybin can significantly decrease MCP-1 and GM-CSF levels. While ketanserin lowers IL-6 and GM-CSF levels, there are no effects seen on TNF-α, IFN-γ, IL-8, or MCP-1. Although synergistic effects between 5-HT2A and TRP channel ligands are minimal in this study, the results provide further evidence of the anti-inflammatory effects of psilocybin and eugenol. Further research is needed to understand the mechanisms of action and the feasibility of using these compounds as anti-inflammatory therapies for conditions like IBD.
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Affiliation(s)
- Gregory Ian Robinson
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Dongping Li
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Bo Wang
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Tahiat Rahman
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Marta Gerasymchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Darryl Hudson
- GoodCap Pharmaceuticals, 520 3rd Avenue SW, Suite 1900, Calgary, AB T2P 0R3, Canada
| | - Olga Kovalchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Igor Kovalchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
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Rahbarnia A, Li Z, Fletcher PJ. Effects of psilocybin, the 5-HT 2A receptor agonist TCB-2, and the 5-HT 2A receptor antagonist M100907 on visual attention in male mice in the continuous performance test. Psychopharmacology (Berl) 2023:10.1007/s00213-023-06474-9. [PMID: 37855864 DOI: 10.1007/s00213-023-06474-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 09/25/2023] [Indexed: 10/20/2023]
Abstract
RATIONALE Neuropsychiatric disorders such as depression are characterized in part by attention deficits. Attention is modulated by the serotonin (5-HT) neurotransmitter system. The 5-HT2A agonist and hallucinogen psilocybin (PSI) is a promising treatment for disorders characterized by attention changes. However, few studies have investigated PSI's direct effect on attention. OBJECTIVE Using the rodent continuous performance task (CPT), we assessed PSI's effect on attention. We also evaluated the impact of 5-HT2A receptor agonist TCB-2 and antagonist M100907 for comparative purposes. METHODS In the CPT, mice learned to distinguish visual targets from non-targets for milkshake reward. Performance was then tested following injections of PSI (0.3, 1, and 3 mg/kg), TCB-2 (0.3, 1, and 3 mg/kg), or M100907 (0.1, 0.3, and 1 mg/kg). Subsequently, drug effects were then evaluated using a more difficult CPT with variable stimulus durations. Mice were then tested on the CPT following repeated PSI injections. Drug effects on locomotor activity were also measured. RESULTS In the CPT, all three drugs reduced hit and false alarm rate and induced conservative responding. PSI also reduced target discrimination. These effects were seen primarily at doses that also significantly reduced locomotor activity. No drug effects were seen on the more difficult CPT or following repeated PSI injections. CONCLUSIONS Psilocybin, TCB-2, and M100907 impaired performance of the CPT. However, this may be in part due to drug-induced locomotor changes. The results provide little support for the idea that psilocybin alters visual attention, or that 5-HT2A receptors modulate this process.
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Affiliation(s)
- Arya Rahbarnia
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada.
- Department of Psychology, University of Toronto, Toronto, ON, Canada.
| | - Zhaoxia Li
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Paul J Fletcher
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychology, University of Toronto, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
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Robinson GI, Li D, Wang B, Zahoruiko Y, Gerasymchuk M, Hudson D, Kovalchuk O, Kovalchuk I. Anti-Inflammatory Effects of Serotonin Receptor and Transient Receptor Potential Channel Ligands in Human Small Intestinal Epithelial Cells. Curr Issues Mol Biol 2023; 45:6743-6774. [PMID: 37623246 PMCID: PMC10453699 DOI: 10.3390/cimb45080427] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 08/09/2023] [Accepted: 08/11/2023] [Indexed: 08/26/2023] Open
Abstract
Intestinal inflammation and dysbiosis can lead to inflammatory bowel diseases (IBD) and systemic inflammation, affecting multiple organs. Developing novel anti-inflammatory therapeutics is crucial for preventing IBD progression. Serotonin receptor type 2A (5-HT2A) ligands, including psilocybin (Psi), 4-Acetoxy-N,N-dimethyltryptamine (4-AcO-DMT), and ketanserin (Ket), along with transient receptor potential (TRP) channel ligands like capsaicin (Cap), curcumin (Cur), and eugenol (Eug), show promise as anti-inflammatory agents. In this study, we investigated the cytotoxic and anti-inflammatory effects of Psi, 4-AcO-DMT, Ket, Cap, Cur, and Eug on human small intestinal epithelial cells (HSEIC). HSEIC were exposed to tumor necrosis factor (TNF)-α and interferon (IFN)-γ for 24 h to induce an inflammatory response, followed by treatment with each compound at varying doses (0-800 μM) for 24 to 96 h. The cytotoxicity was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and protein expression by Western blot (WB) analysis. As single treatments, Psi (40 μM), Cur (0.5 μM), and Eug (50 μM) significantly reduced COX-2 levels without cytotoxic effects. When combined, Psi (40 μM) and Cur (0.5 μM) exhibited synergy, resulting in a substantial decrease in COX-2 protein levels (-28× fold change), although the reduction in IL-6 was less pronounced (-1.6× fold change). Psi (20 μM) and Eug (25 μM) demonstrated the most favorable outcomes, with significant decreases in COX-2 (-19× fold change) and IL-6 (-10× fold change) protein levels. Moreover, the combination of Psi and Eug did not induce cytotoxic effects in vitro at any tested doses. This study is the first to explore the anti-inflammatory potential of psilocybin and 4-AcO-DMT in the intestines while highlighting the potential for synergy between the 5-HT2A and TRP channel ligands, specifically Psi and Eug, in alleviating the TNF-α/IFN-γ-induced inflammatory response in HSEIC. Further investigations should evaluate if the Psi and Eug combination has the therapeutic potential to treat IBD in vivo.
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Affiliation(s)
- Gregory Ian Robinson
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada; (G.I.R.); (M.G.)
| | - Dongping Li
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada; (G.I.R.); (M.G.)
| | - Bo Wang
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada; (G.I.R.); (M.G.)
| | - Yeva Zahoruiko
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada; (G.I.R.); (M.G.)
| | - Marta Gerasymchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada; (G.I.R.); (M.G.)
| | - Darryl Hudson
- GoodCap Pharmaceuticals, Calgary, AB T2P 0R3, Canada
| | - Olga Kovalchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada; (G.I.R.); (M.G.)
| | - Igor Kovalchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada; (G.I.R.); (M.G.)
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Poppe C, Trachsel M. The Road to Ixtlan in Neuro-Degenerative Diseases Is Paved with Palliative Cobblestones. AJOB Neurosci 2023; 14:134-136. [PMID: 37097859 DOI: 10.1080/21507740.2023.2188295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2023]
Affiliation(s)
| | - Manuel Trachsel
- University Hospital Basel (USB), University Psychiatric Clinics (UPK) Basel, Geriatric University Hospital Felix Platter (UAFP), and University Children's Hospital Basel (UKBB)
- University of Basel
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12
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Buzzelli V, Carbone E, Manduca A, Schiavi S, Feo A, Perederiy JV, Ambert KH, Hausman M, Trezza V. Psilocybin mitigates the cognitive deficits observed in a rat model of Fragile X syndrome. Psychopharmacology (Berl) 2023; 240:137-147. [PMID: 36469097 DOI: 10.1007/s00213-022-06286-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 11/20/2022] [Indexed: 12/12/2022]
Abstract
RATIONALE Fragile X syndrome (FXS) is the most common form of inherited intellectual disability (ID) and the leading monogenic cause of autism spectrum disorder (ASD). Serotonergic neurotransmission has a key role in the modulation of neuronal activity during development, and therefore, it has been hypothesized to be involved in ASD and co-occurring conditions including FXS. As serotonin is involved in synaptic remodeling and maturation, serotonergic insufficiency during childhood may have a compounding effect on brain patterning in neurodevelopmental disorders, manifesting as behavioral and emotional symptoms. Thus, compounds that stimulate serotonergic signaling such as psilocybin may offer promise as effective early interventions for developmental disorders such as ASD and FXS. OBJECTIVES The aim of the present study was to test whether different protocols of psilocybin administration mitigate cognitive deficits displayed by the recently validated Fmr1-Δexon 8 rat model of ASD, which is also a model of FXS. RESULTS Our results revealed that systemic and oral administration of psilocybin microdoses normalizes the aberrant cognitive performance displayed by adolescent Fmr1-Δexon 8 rats in the short-term version of the novel object recognition test-a measure of exploratory behavior, perception, and recognition. CONCLUSIONS These data support the hypothesis that serotonin-modulating drugs such as psilocybin may be useful to ameliorate ASD-related cognitive deficits. Overall, this study provides evidence of the beneficial effects of different schedules of psilocybin treatment in mitigating the short-term cognitive deficit observed in a rat model of FXS.
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Affiliation(s)
- Valeria Buzzelli
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Viale G. Marconi 446, 00146, Rome, Italy
| | - Emilia Carbone
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Viale G. Marconi 446, 00146, Rome, Italy
| | - Antonia Manduca
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Viale G. Marconi 446, 00146, Rome, Italy.,Neuroendocrinology, Metabolism and Neuropharmacology Unit, IRCSS Fondazione Santa Lucia, Rome, Italy
| | - Sara Schiavi
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Viale G. Marconi 446, 00146, Rome, Italy
| | - Alessandro Feo
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Viale G. Marconi 446, 00146, Rome, Italy
| | | | - Kyle H Ambert
- Nova Mentis Life Science Corp., Vancouver, BC, Canada
| | | | - Viviana Trezza
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Viale G. Marconi 446, 00146, Rome, Italy.
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13
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Could psychedelic drugs have a role in the treatment of schizophrenia? Rationale and strategy for safe implementation. Mol Psychiatry 2023; 28:44-58. [PMID: 36280752 DOI: 10.1038/s41380-022-01832-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 10/02/2022] [Accepted: 10/07/2022] [Indexed: 01/07/2023]
Abstract
Schizophrenia is a widespread psychiatric disorder that affects 0.5-1.0% of the world's population and induces significant, long-term disability that exacts high personal and societal cost. Negative symptoms, which respond poorly to available antipsychotic drugs, are the primary cause of this disability. Association of negative symptoms with cortical atrophy and cell loss is widely reported. Psychedelic drugs are undergoing a significant renaissance in psychiatric disorders with efficacy reported in several conditions including depression, in individuals facing terminal cancer, posttraumatic stress disorder, and addiction. There is considerable evidence from preclinical studies and some support from human studies that psychedelics enhance neuroplasticity. In this Perspective, we consider the possibility that psychedelic drugs could have a role in treating cortical atrophy and cell loss in schizophrenia, and ameliorating the negative symptoms associated with these pathological manifestations. The foremost concern in treating schizophrenia patients with psychedelic drugs is induction or exacerbation of psychosis. We consider several strategies that could be implemented to mitigate the danger of psychotogenic effects and allow treatment of schizophrenia patients with psychedelics to be implemented. These include use of non-hallucinogenic derivatives, which are currently the focus of intense study, implementation of sub-psychedelic or microdosing, harnessing of entourage effects in extracts of psychedelic mushrooms, and blocking 5-HT2A receptor-mediated hallucinogenic effects. Preclinical studies that employ appropriate animal models are a prerequisite and clinical studies will need to be carefully designed on the basis of preclinical and translational data. Careful research in this area could significantly impact the treatment of one of the most severe and socially debilitating psychiatric disorders and open an exciting new frontier in psychopharmacology.
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DellaCrosse M, Pleet M, Morton E, Ashtari A, Sakai K, Woolley J, Michalak E. "A sense of the bigger picture:" A qualitative analysis of follow-up interviews with people with bipolar disorder who self-reported psilocybin use. PLoS One 2022; 17:e0279073. [PMID: 36516137 PMCID: PMC9749989 DOI: 10.1371/journal.pone.0279073] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 11/30/2022] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVES People with bipolar disorder (BD) spend more time depressed than manic/hypomanic, and depression is associated with greater impairments in psychosocial functioning and quality of life than mania/hypomania. Emerging evidence suggests psilocybin, the psychoactive compound in "magic mushrooms," is a promising treatment for unipolar depression. Clinical trials of psilocybin therapy have excluded people with BD as a precaution against possible adverse effects (e.g., mania). Our study centered the experiences of adults living with BD who consumed psilocybin-containing mushrooms, and aimed to (1) understand its subjective impacts on BD symptoms, (2) deepen understanding of Phase I survey results, and (3) elucidate specific contextual factors associated with adverse reactions in naturalistic settings. METHODS Following an international survey (Phase I), follow-up interviews were conducted with 15 respondents (Phase II) to further understand psilocybin use among adults with BD. As part of a larger mixed-methods explanatory sequential design study, reflexive thematic analysis was used to elaborate findings. RESULTS Three major themes containing sub-themes were developed. (1) Mental Health Improvements: (1.1) decreased impact and severity of depression, (1.2) increased emotion processing, (1.3) development of new perspectives, and (1.4) greater relaxation and sleep. (2) Undesired Mental Health Impacts: (2.1) changes in sleep, (2.2) increased mania severity, (2.3) hospitalization, and (2.4) distressing sensory experiences. (3) Salient Contextual Factors for psilocybin use included: (3.1) poly-substance use and psilocybin dose, (3.2) solo versus social experiences, and (3.3) pre-psilocybin sleep deprivation. CONCLUSION Our findings demonstrate both benefits and risks of psilocybin use in this population. Carefully designed clinical trials focused on safety and preliminary efficacy are warranted.
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Affiliation(s)
- Meghan DellaCrosse
- Department of Clinical Psychology, The Wright Institute, Berkeley, California, United States of America
- Department of Psychiatry and Behavioral Sciences, University of California, San Francisco, San Francisco, California, United States of America
- San Francisco Veteran’s Affairs Medical Center, San Francisco, California, United States of America
- Department of Psychiatry and Behavioral Health, The Ohio State University, Columbus, Ohio, United States of America
| | - Mollie Pleet
- Department of Psychiatry and Behavioral Sciences, University of California, San Francisco, San Francisco, California, United States of America
- San Francisco Veteran’s Affairs Medical Center, San Francisco, California, United States of America
| | - Emma Morton
- Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Amir Ashtari
- Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kimberly Sakai
- Department of Psychiatry and Behavioral Sciences, University of California, San Francisco, San Francisco, California, United States of America
- San Francisco Veteran’s Affairs Medical Center, San Francisco, California, United States of America
| | - Josh Woolley
- Department of Psychiatry and Behavioral Sciences, University of California, San Francisco, San Francisco, California, United States of America
- San Francisco Veteran’s Affairs Medical Center, San Francisco, California, United States of America
| | - Erin Michalak
- Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada
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15
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Moujaes F, Preller KH, Ji JL, Murray JD, Berkovitch L, Vollenweider FX, Anticevic A. Towards mapping neuro-behavioral heterogeneity of psychedelic neurobiology in humans. Biol Psychiatry 2022:S0006-3223(22)01805-4. [PMID: 36715317 DOI: 10.1016/j.biopsych.2022.10.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 10/10/2022] [Accepted: 10/31/2022] [Indexed: 12/12/2022]
Abstract
Precision psychiatry aims to identify markers of inter-individual variability that allow predicting the right treatment for each patient. However, bridging the gap between molecular-level manipulations and neural systems-level functional alterations remains an unsolved problem in psychiatry. After decades of low success rates in pharmaceutical R&D for psychiatric drugs, multiple studies now point to the potential of psychedelics as a promising fast-acting and long-lasting treatment for some psychiatric symptoms. Yet, given the highly psychoactive nature of these substances, a precision medicine approach is essential to map the neural signals related to clinical efficacy in order to identify patients who can maximally benefit from this treatment. Recent studies have shown that bridging the gap between pharmacology, systems-level neural response in humans and individual experience is possible for psychedelic substances, therefore paving the way for a precision neuropsychiatric therapeutic development. Specifically, it has been shown that the integration of brain-wide PET or transcriptomic data, i.e. receptor distribution for the serotonin 2A receptor, with computational neuroimaging methods can simulate the effect of psychedelics on the human brain. These novel 'computational psychiatry' approaches allow for modeling inter-individual differences in neural as well as subjective effects of psychedelic substances. Collectively, this review provides a deep dive into psychedelic pharmaco-neuroimaging studies with a core focus on how recent computational psychiatry advances in biophysically based circuit modeling can be leveraged to predict individual responses. Finally, we emphasize the importance of human pharmacological neuroimaging for the continued precision therapeutic development of psychedelics.
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Affiliation(s)
- Flora Moujaes
- Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital for Psychiatry Zurich, Lenggstr. 31, 8032 Zurich, Switzerland; Department of Psychiatry, Yale University School of Medicine, 40 Temple Street, New Haven, CT, 06511, United States
| | - Katrin H Preller
- Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital for Psychiatry Zurich, Lenggstr. 31, 8032 Zurich, Switzerland; Department of Psychiatry, Yale University School of Medicine, 40 Temple Street, New Haven, CT, 06511, United States
| | - Jie Lisa Ji
- Department of Psychiatry, Yale University School of Medicine, 40 Temple Street, New Haven, CT, 06511, United States
| | - John D Murray
- Department of Psychiatry, Yale University School of Medicine, 40 Temple Street, New Haven, CT, 06511, United States; Department of Physics, Yale University, New Haven, CT, 06511, United States; Interdepartmental Neuroscience Program, Yale University, New Haven, CT, 06511, United States
| | - Lucie Berkovitch
- Department of Psychiatry, Yale University School of Medicine, 40 Temple Street, New Haven, CT, 06511, United States; Université de Paris, 15 Rue de l'École de Médecine, F-75006 Paris, France; Department of Psychiatry, Service Hospitalo-Universitaire, GHU Paris Psychiatrie & Neurosciences, 1 rue Cabanis, F-75014, Paris, France
| | - Franz X Vollenweider
- Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital for Psychiatry Zurich, Lenggstr. 31, 8032 Zurich, Switzerland
| | - Alan Anticevic
- Department of Psychiatry, Yale University School of Medicine, 40 Temple Street, New Haven, CT, 06511, United States; Interdepartmental Neuroscience Program, Yale University, New Haven, CT, 06511, United States.
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16
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Ona G, Kohek M, Bouso JC. The illusion of knowledge in the emerging field of psychedelic research. NEW IDEAS IN PSYCHOLOGY 2022. [DOI: 10.1016/j.newideapsych.2022.100967] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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17
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Hartogsohn I, Petranker R. Set and setting in microdosing: an oft-overlooked principle. Psychopharmacology (Berl) 2022; 239:3771-3777. [PMID: 36289109 DOI: 10.1007/s00213-022-06249-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 09/24/2022] [Indexed: 11/24/2022]
Abstract
RATIONALE The use of psychedelics for medical and recreational purposes is rising. Contextual factors such as expectancy, intention, and sensory and social environment (set and setting) are widely recognized as moderating the effects of these substances. Nevertheless, clinical trials of microdosing - the ingestion of small, sub-hallucinogenic doses of psychedelics - rarely report their set and setting. This fact suggests that such factors are not considered important in the context of microdosing. OBJECTIVE This paper challenges this assumption and makes the case for the crucial relevance of set and setting in microdosing practice. Building on set and setting theory and placebo theory, we explain why set and setting are of crucial importance in the case of microdosing. RESULTS This reasoning helps elucidate the role of set and setting in determining the outcomes of microdosing and helps explain some of the contradictory results that have emerged in microdosing research in recent years. CONCLUSION Set and setting are important constructs to be considered especially in the context of microdosing psychedelics. By reporting set and setting, the results of microdosing research can be made more reliable and consistent.
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Affiliation(s)
- Ido Hartogsohn
- The Program for Science, Technology and Society Studies, Bar Ilan University, Ramat Gan, Israel
| | - Rotem Petranker
- Department of Psychology, McMaster University, Hamilton, ON, Canada.
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18
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Natural language signatures of psilocybin microdosing. Psychopharmacology (Berl) 2022; 239:2841-2852. [PMID: 35676541 DOI: 10.1007/s00213-022-06170-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 05/26/2022] [Indexed: 10/18/2022]
Abstract
RATIONALE Serotonergic psychedelics are being studied as novel treatments for mental health disorders and as facilitators of improved well-being, mental function, and creativity. Recent studies have found mixed results concerning the effects of low doses of psychedelics ("microdosing") on these domains. However, microdosing is generally investigated using instruments designed to assess larger doses of psychedelics, which might lack sensitivity and specificity for this purpose. OBJECTIVES Determine whether unconstrained speech contains signatures capable of identifying the acute effects of psilocybin microdoses. METHODS Natural speech under psilocybin microdoses (0.5 g of psilocybin mushrooms) was acquired from thirty-four healthy adult volunteers (11 females: 32.09 ± 3.53 years; 23 males: 30.87 ± 4.64 years) following a double-blind and placebo-controlled experimental design with two measurement weeks per participant. On Wednesdays and Fridays of each week, participants consumed either the active dose (psilocybin) or the placebo (edible mushrooms). Features of interest were defined based on variables known to be affected by higher doses: verbosity, semantic variability, and sentiment scores. Machine learning models were used to discriminate between conditions. Classifiers were trained and tested using stratified cross-validation to compute the AUC and p-values. RESULTS Except for semantic variability, these metrics presented significant differences between a typical active microdose and the inactive placebo condition. Machine learning classifiers were capable of distinguishing between conditions with high accuracy (AUC [Formula: see text] 0.8). CONCLUSIONS These results constitute first evidence that low doses of serotonergic psychedelics can be identified from unconstrained natural speech, with potential for widely applicable, affordable, and ecologically valid monitoring of microdosing schedules.
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19
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Microdosing with psilocybin mushrooms: a double-blind placebo-controlled study. Transl Psychiatry 2022; 12:307. [PMID: 35918311 PMCID: PMC9346139 DOI: 10.1038/s41398-022-02039-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 06/21/2022] [Accepted: 06/29/2022] [Indexed: 12/12/2022] Open
Abstract
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.
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20
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van Elk M, Yaden DB. Pharmacological, neural, and psychological mechanisms underlying psychedelics: A critical review. Neurosci Biobehav Rev 2022; 140:104793. [PMID: 35878791 DOI: 10.1016/j.neubiorev.2022.104793] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 07/08/2022] [Accepted: 07/20/2022] [Indexed: 10/17/2022]
Abstract
This paper provides a critical review of several possible mechanisms at different levels of analysis underlying the effects and therapeutic potential of psychedelics. At the (1) biochemical level, psychedelics primarily affect the 5-HT2A receptor, increase neuroplasticity, offer a critical period for social reward learning, and have anti-inflammatory properties. At the (2) neural level, psychedelics have been associated with reduced efficacy of thalamo-cortical filtering, the loosening of top-down predictive signaling and an increased sensitivity to bottom-up prediction errors, and activation of the claustro-cortical-circuit. At the (3) psychological level, psychedelics have been shown to induce altered and affective states, they affect cognition, induce belief change, exert social effects, and can result in lasting changes in behavior. We outline the potential for a unifying account of the mechanisms underlying psychedelics and contrast this with a model of pluralistic causation. Ultimately, a better understanding of the specific mechanisms underlying the effects of psychedelics could allow for a more targeted therapeutic approach. We highlight current challenges for psychedelic research and provide a research agenda to foster insight in the causal-mechanistic pathways underlying the efficacy of psychedelic research and therapy.
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Affiliation(s)
- Michiel van Elk
- Institute of Psychology, Leiden University, Wassenaarseweg 52, 2333 AK Leiden, the Netherlands.
| | - David Bryce Yaden
- The Center for Psychedelic and Consciousness Research, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, USA
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21
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Psilocybin microdosers demonstrate greater observed improvements in mood and mental health at one month relative to non-microdosing controls. Sci Rep 2022; 12:11091. [PMID: 35773270 PMCID: PMC9246852 DOI: 10.1038/s41598-022-14512-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 06/08/2022] [Indexed: 12/12/2022] Open
Abstract
Psilocybin microdosing involves repeated self-administration of mushrooms containing psilocybin at doses small enough to not impact regular functioning. Microdose practices are diverse and include combining psilocybin with substances such as lion’s mane mushrooms (Hericium erinaceus; HE) and niacin (vitamin-B3). Public uptake of microdosing has outpaced evidence, mandating further prospective research. Using a naturalistic, observational design, we followed psilocybin microdosers (n = 953) and non-microdosing comparators (n = 180) for approximately 30 days and identified small- to medium-sized improvements in mood and mental health that were generally consistent across gender, age and presence of mental health concerns, as we all as improvements in psychomotor performance that were specific to older adults. Supplementary analyses indicated that combining psilocybin with HE and B3 did not impact changes in mood and mental health. However, among older microdosers combining psilocybin, HE and B3 was associated with psychomotor improvements relative to psilocybin alone and psilocybin and HE. Our findings of mood and mental health improvements associated with psilocybin microdosing add to previous studies of psychedelic microdosing by using a comparator group and by examining the consistency of effects across age, gender, and mental health. Findings regarding the combination of psilocybin, HE and B3 are novel and highlight the need for further research to confirm and elucidate these apparent effects.
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22
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Weimer MB, Fiellin DA. Low- and very low-dose buprenorphine induction: new(ish) uses for an old(ish) medication? Addiction 2022; 117:1507-1509. [PMID: 35032081 DOI: 10.1111/add.15799] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 12/27/2021] [Indexed: 12/01/2022]
Affiliation(s)
- Melissa B Weimer
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, USA.,Program in Addiction Medicine, Yale School of Medicine, New Haven, CT, USA.,Yale School of Public Health, New Haven, CT, USA
| | - David A Fiellin
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, USA.,Program in Addiction Medicine, Yale School of Medicine, New Haven, CT, USA.,Yale School of Public Health, New Haven, CT, USA.,Department of Emergency Medicine, Yale School of Medicine, New Haven, CT, USA
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23
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Polito V, Liknaitzky P. The emerging science of microdosing: A systematic review of research on low dose psychedelics (1955 - 2021) and recommendations for the field. Neurosci Biobehav Rev 2022; 139:104706. [PMID: 35609684 DOI: 10.1016/j.neubiorev.2022.104706] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 05/09/2022] [Accepted: 05/18/2022] [Indexed: 12/20/2022]
Abstract
The use of low doses of psychedelic substances (microdosing) is attracting increasing interest. This systematic review summarises all empirical microdosing research to date, including a set of infrequently cited studies that took place prior to prohibition. Specifically, we reviewed 44 studies published between 1955 and 2021, and summarised reported effects across six categories: mood and mental health; wellbeing and attitude; cognition and creativity; personality; changes in conscious state; and neurobiology and physiology. Studies showed a wide range in risk of bias, depending on design, age, and other study characteristics. Laboratory studies found changes in pain perception, time perception, conscious state, and neurophysiology. Self-report studies found changes in cognitive processing and mental health. We review data related to expectation and placebo effects, but argue that claims that microdosing effects are largely due to expectancy are premature and possibly wrong. In addition, we attempt to clarify definitional inconsistencies in the microdosing literature by providing suggested dose ranges across different substances. Finally, we provide specific design suggestions to facilitate more rigorous future research.
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Affiliation(s)
- Vince Polito
- School of Psychological Sciences, Macquarie University, Australia.
| | - Paul Liknaitzky
- Turner Institute, School of Psychological Sciences, Monash University, Australia; Department of Psychiatry, School of Clinical Sciences, Monash University, Australia.
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24
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Huang J, Pham M, Panenka WJ, Honer WG, Barr AM. Chronic Treatment With Psilocybin Decreases Changes in Body Weight in a Rodent Model of Obesity. Front Psychiatry 2022; 13:891512. [PMID: 35664477 PMCID: PMC9157591 DOI: 10.3389/fpsyt.2022.891512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 04/27/2022] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND There are currently relatively few effective pharmacological treatments for obesity, and existing ones may be associated with limiting side-effects. In the search for novel anti-obesity agents, drugs that modify central serotonergic systems have historically proven to be effective in promoting weight loss. Psilocin, which is rapidly metabolized from psilocybin, is an agonist at multiple serotonin receptors. In the present study we assessed the effects of psilocybin and a positive control (metformin) on changes in body weight in a rat model of obesity. METHODS Five groups of adult male rats were pre-conditioned with a cafeteria diet until obese (>600 g) and then treated with either psilocybin (0.1, 1, or 5 mg/kg, i.p.), metformin (300 mg/kg, p.o.) or vehicle control. Treatments were for 27 consecutive weekdays, and body weights and high calorie food intake were recorded daily. Fasting glucose levels were recorded after 11 days of treatment. At the end of treatment rats completed a glucose tolerance test, and multiple fat pads were dissected out to assess adiposity. RESULTS The medium dose psilocybin group had to be terminated from the study prematurely. Both the low and high dose psilocybin groups caused a significant decrease in changes in body weight compared to controls. The metformin group produced a greater decrease in change in body weight than either psilocybin groups or controls. Both high dose psilocybin and metformin decreased consumption of the high calorie diet, and exhibited decreased central adiposity. CONCLUSION Psilocybin demonstrated modest but significant effects on weight gain. Further study is recommended.
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Affiliation(s)
- Joyce Huang
- Department of Anesthesiology, Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Michelle Pham
- Department of Anesthesiology, Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - William J Panenka
- Department of Psychiatry, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.,British Columbia Mental Health & Substance Use Services Research Institute, Vancouver, BC, Canada
| | - William G Honer
- Department of Psychiatry, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.,British Columbia Mental Health & Substance Use Services Research Institute, Vancouver, BC, Canada
| | - Alasdair M Barr
- Department of Anesthesiology, Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.,British Columbia Mental Health & Substance Use Services Research Institute, Vancouver, BC, Canada
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25
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van den Berg M, Magaraggia I, Schreiber R, Hillhouse TM, Porter JH. How to account for hallucinations in the interpretation of the antidepressant effects of psychedelics: a translational framework. Psychopharmacology (Berl) 2022; 239:1853-1879. [PMID: 35348806 PMCID: PMC9166823 DOI: 10.1007/s00213-022-06106-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 02/24/2022] [Indexed: 01/02/2023]
Abstract
RATIONALE Recent trials with psychedelics in major depressive disorder and treatment-resistant depression showed remarkable improvements in depressive symptoms that can last for up to several months after even a single administration. The lack of an appropriate placebo control group-as patients are often able to discriminate the subjective effects of the drug-and an incomplete understanding of the role of the hallucinogenic and mystical experience, hampers the interpretation of these therapeutic effects. OBJECTIVES To control for these factors, we developed a translational framework based on establishing pharmacokinetic/pharmacodynamic (PK/PD) relationships in rodents and humans for hallucinogenic (i.e., discriminative stimulus effects in rodents and humans; head twitch responses in rodents; questionnaires in humans) and therapeutic effects. For the latter, we selected the pattern separation and attentional set-shifting tasks as measures for cognitive flexibility because of their high translational value. We predict that these PK/PD analyses will lead to a more objective evaluation of improvements in patients compared to relying only on the currently used self-reported questionnaires. We hypothesize that-if the role of the hallucinogenic experience is not central in the antidepressant effects of psychedelics-the ED50's for the therapeutic effects will be significantly lower than for the hallucinogenic and mystical effects. CONCLUSION Our framework will help to inform future studies that aim at the elucidation of the mechanism(s) of action of psychedelics in depression, and the role of the acute subjective and/or hallucinogenic experience in their effects.
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Affiliation(s)
- Manon van den Berg
- Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands ,Faculty of Psychology and Neuroscience, Section Neuropsychology & Psychopharmacology, Maastricht University, Maastricht, The Netherlands
| | - Igor Magaraggia
- Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands ,Faculty of Psychology and Neuroscience, Section Neuropsychology & Psychopharmacology, Maastricht University, Maastricht, The Netherlands
| | - Rudy Schreiber
- Faculty of Psychology and Neuroscience, Section Neuropsychology & Psychopharmacology, Maastricht University, Maastricht, The Netherlands.
| | - Todd M. Hillhouse
- Department of Psychology, University of Wisconsin Green Bay, Green Bay, WI USA
| | - Joseph H. Porter
- Department of Psychology, Virginia Commonwealth University, Richmond, USA
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Rootman JM, Kryskow P, Harvey K, Stamets P, Santos-Brault E, Kuypers KPC, Polito V, Bourzat F, Walsh Z. Adults who microdose psychedelics report health related motivations and lower levels of anxiety and depression compared to non-microdosers. Sci Rep 2021; 11:22479. [PMID: 34795334 PMCID: PMC8602275 DOI: 10.1038/s41598-021-01811-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 10/28/2021] [Indexed: 02/07/2023] Open
Abstract
The use of psychedelic substances at sub-sensorium 'microdoses', has gained popular academic interest for reported positive effects on wellness and cognition. The present study describes microdosing practices, motivations and mental health among a sample of self-selected microdosers (n = 4050) and non-microdosers (n = 4653) via a mobile application. Psilocybin was the most commonly used microdose substances in our sample (85%) and we identified diverse microdose practices with regard to dosage, frequency, and the practice of stacking which involves combining psilocybin with non-psychedelic substances such as Lion's Mane mushrooms, chocolate, and niacin. Microdosers were generally similar to non-microdosing controls with regard to demographics, but were more likely to report a history of mental health concerns. Among individuals reporting mental health concerns, microdosers exhibited lower levels of depression, anxiety, and stress across gender. Health and wellness-related motives were the most prominent motives across microdosers in general, and were more prominent among females and among individuals who reported mental health concerns. Our results indicate health and wellness motives and perceived mental health benefits among microdosers, and highlight the need for further research into the mental health consequences of microdosing including studies with rigorous longitudinal designs.
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Affiliation(s)
- Joseph M Rootman
- Department of Psychology, University of British Columbia, Kelowna, BC, Canada.
| | - Pamela Kryskow
- Department of Family Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Kalin Harvey
- Quantified Citizen Technologies Inc., Vancouver, BC, Canada
| | | | | | - Kim P C Kuypers
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Vince Polito
- Department of Cognitive Science, Macquarie University, Sydney, Australia
| | | | - Zach Walsh
- Department of Psychology, University of British Columbia, Kelowna, BC, Canada
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Grambow E, Sorg H, Sorg CGG, Strüder D. Experimental Models to Study Skin Wound Healing with a Focus on Angiogenesis. Med Sci (Basel) 2021; 9:medsci9030055. [PMID: 34449673 PMCID: PMC8395822 DOI: 10.3390/medsci9030055] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 08/16/2021] [Accepted: 08/18/2021] [Indexed: 12/11/2022] Open
Abstract
A large number of models are now available for the investigation of skin wound healing. These can be used to study the processes that take place in a phase-specific manner under both physiological and pathological conditions. Most models focus on wound closure, which is a crucial parameter for wound healing. However, vascular supply plays an equally important role and corresponding models for selective or parallel investigation of microcirculation regeneration and angiogenesis are also described. In this review article, we therefore focus on the different levels of investigation of skin wound healing (in vivo to in virtuo) and the investigation of angiogenesis and its parameters.
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Affiliation(s)
- Eberhard Grambow
- Department of General, Visceral, Thoracic, Vascular and Transplantation Surgery, Rostock University Medical Center, 18057 Rostock, Germany
- Correspondence:
| | - Heiko Sorg
- Department of Health, University of Witten/Herdecke, Alfred-Herrhausen-Str. 50, 58455 Witten, Germany;
- Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, Klinikum Westfalen, Am Knappschaftskrankenhaus 1, 44309 Dortmund, Germany
| | - Christian G. G. Sorg
- Chair of Management and Innovation in Health Care, Department of Management and Entrepreneurship, Faculty of Management, Economics and Society, Witten/Herdecke University, Alfred-Herrhausen-Straße 50, 58455 Witten, Germany;
| | - Daniel Strüder
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery “Otto Körner”, Rostock University Medical Center, 18057 Rostock, Germany;
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Révész D, Ona G, Rossi GN, Rocha JM, Dos Santos RG, Hallak JEC, Alcázar-Córcoles MÁ, Bouso JC. Cross-Sectional Associations Between Lifetime Use of Psychedelic Drugs and Psychometric Measures During the COVID-19 Confinement: A Transcultural Study. Front Psychiatry 2021; 12:687546. [PMID: 34220590 PMCID: PMC8242180 DOI: 10.3389/fpsyt.2021.687546] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 05/25/2021] [Indexed: 01/07/2023] Open
Abstract
Background: One of the main public health strategies adopted at the beginning of the COVID-19 pandemic consisted of implementing strict lockdowns to stop the transmission of the virus. Despite being an effective measure, the confinement and the associated social isolation create a stressful, potentially lengthy situations that has been proven to have several psychological consequences. Given the potential benefits that certain psychedelic drugs have shown for the treatment of psychological disorders, this study aimed to assess the impact of lifetime psychedelic drug use on mental health in relation to the first strict lockdown adopted by various countries (April-July 2020). Methods: Subjects completed an online survey that inquired about sociodemographic factors, activities, and lifestyle factors during confinement, as well as health and mental health related factors. Subjects were asked about their lifetime use of psychedelic drugs (MDMA, ayahuasca, psilocybin-containing mushrooms, LSD, peyote, San Pedro, Bufo alvarius or 5-MeO-DMT, and others), being classified as regular users (more than once per 6 months), occasional users, or non-users. The survey included psychometric tests used to assess psychological distress, peritraumatic stress, social support, psychopathological symptoms, and personality. Linear regressions were performed with psychedelic drug users as the independent variable and psychometric factors as the outcomes, while correcting for age, gender, language, religion, spirituality, and use of non-psychedelic drugs. Results: The study included 2,974 English, Portuguese, and Spanish speakers (497 regular users of psychedelic drugs, 606 occasional users, and 1,968 non-users). On average, respondents were 36 years old and 70% were female. Psychedelic drug users, especially regular ones, reported less psychological distress, less peritraumatic stress, and more social support. Regarding personality measures, psychedelic drug users scored higher on the novelty-seeking and self-transcendence scales, and lower on cooperativeness. Conclusion: Our findings showed that regular users of psychedelic drugs had less psychological stress and some personality differences when compared to occasional users and non-users. This suggests that either the use of psychedelics might be a protective factor itself or people with certain previous traits are more prone to frequently using psychedelic drugs. Future prospective longitudinal research should investigate the underlying processes observed in this study to develop consistent hypotheses.
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Affiliation(s)
- Dóra Révész
- Center of Research on Psychological and Somatic Disorders (CoRPS), Department of Medical and Clinical Psychology, Tilburg University, Tilburg, Netherlands
| | - Genís Ona
- ICEERS-International Center for Ethnobotanical Education, Research, and Service, Barcelona, Spain.,Medical Anthropology Research Center (MARC), Universitat Rovira i Virgili, Tarragona, Spain
| | - Giordano N Rossi
- Department of Neurosciences and Behavior, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Juliana M Rocha
- Department of Neurosciences and Behavior, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Rafael G Dos Santos
- ICEERS-International Center for Ethnobotanical Education, Research, and Service, Barcelona, Spain.,Department of Neurosciences and Behavior, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil.,National Institute of Science and Technology-Translational Medicine, São Paulo, Brazil
| | - Jaime E C Hallak
- Department of Neurosciences and Behavior, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil.,National Institute of Science and Technology-Translational Medicine, São Paulo, Brazil
| | - Miguel Á Alcázar-Córcoles
- Department of Biological and Health Psychology, School of Psychology, Autonomous University of Madrid (UAM), Madrid, Spain
| | - José C Bouso
- ICEERS-International Center for Ethnobotanical Education, Research, and Service, Barcelona, Spain.,Medical Anthropology Research Center (MARC), Universitat Rovira i Virgili, Tarragona, Spain.,Department of Neurosciences and Behavior, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
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