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Orłowski P, Hobot J, Ruban A, Szczypiński J, Bola M. Naturalistic use of psychedelics does not modulate processing of self-related stimuli (but it might modulate attentional mechanisms): An event-related potentials study. Psychophysiology 2024; 61:e14583. [PMID: 38584307 DOI: 10.1111/psyp.14583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 03/22/2024] [Accepted: 03/26/2024] [Indexed: 04/09/2024]
Abstract
Classic psychedelics are able to profoundly alter the state of consciousness and lead to acute experiences of ego dissolution - the blurring of the distinction between representations of self and the external world. However, whether repeated use of psychedelics is associated with more prolonged and permanent modifications to the concept of self remains to be investigated. Therefore, we conducted a preregistered, cross-sectional study in which experienced psychedelics users (15 or more lifetime experiences with psychedelics; N = 56) were compared to nonusers (N = 57) in terms of neural reactivity to a Self-name (i.e., each participant's own name) stimulus, which is known to robustly activate a representation of self. Two control stimuli were additionally used: an Other-name stimulus, as a passive control condition in which no reaction was required, and a Target-name stimulus, to which participants provided a manual response and which thus constituted an active control condition. Analysis of the amplitude of the P300 ERP component evoked by the Self- or Target-names revealed no difference between the psychedelics users and nonusers. However, psychedelic users exhibited increased P300 amplitude during perception of Other-names. In addition, in comparison to nonusers, psychedelics users exhibited a smaller increase in P300 amplitude when processing the task-relevant Target-names (in relation to both Self- and Other-names). Therefore, our data suggests that regular naturalistic use of psychedelics may not be related to long-term changes in the representation of self, but it might potentially affect the allocation of attentional resources to task-relevant stimuli.
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Affiliation(s)
- Paweł Orłowski
- Centre for Brain Research, Jagiellonian University, Kraków, Poland
- Doctoral School in the Social Sciences, Jagiellonian University, Kraków, Poland
| | - Justyna Hobot
- Consciousness Lab, Psychology Institute, Jagiellonian University, Kraków, Poland
| | - Anastasia Ruban
- Department of Psychology, SWPS University of Social Sciences and Humanities, Warsaw, Poland
| | - Jan Szczypiński
- Department of Psychiatry, Medical University of Warsaw, Warsaw, Poland
| | - Michał Bola
- Centre for Brain Research, Jagiellonian University, Kraków, Poland
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Mortaheb S, Fort LD, Mason NL, Mallaroni P, Ramaekers JG, Demertzi A. Dynamic Functional Hyperconnectivity After Psilocybin Intake Is Primarily Associated With Oceanic Boundlessness. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2024; 9:681-692. [PMID: 38588855 DOI: 10.1016/j.bpsc.2024.04.001] [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: 01/20/2024] [Revised: 03/28/2024] [Accepted: 04/01/2024] [Indexed: 04/10/2024]
Abstract
BACKGROUND Psilocybin is a widely studied psychedelic substance that leads to the psychedelic state, a specific altered state of consciousness. To date, the relationship between the psychedelic state's neurobiological and experiential patterns remains undercharacterized because they are often analyzed separately. We investigated the relationship between neurobiological and experiential patterns after psilocybin by focusing on the link between dynamic cerebral connectivity and retrospective questionnaire assessment. METHODS Healthy participants were randomized to receive either psilocybin (n = 22) or placebo (n = 27) and scanned for 6 minutes in an eyes-open resting state during the peak subjective drug effect (102 minutes posttreatment) in ultrahigh field 7T magnetic resonance imaging. The 5-Dimensional Altered States of Consciousness Rating Scale was administered 360 minutes after drug intake. RESULTS Under psilocybin, there were alterations across all dimensions of the 5-Dimensional Altered States of Consciousness Rating Scale and widespread increases in averaged brain functional connectivity. Time-varying functional connectivity analysis unveiled a recurrent hyperconnected pattern characterized by low blood oxygen level-dependent signal amplitude, suggesting heightened cortical arousal. In terms of neuroexperiential links, canonical correlation analysis showed higher transition probabilities to the hyperconnected pattern with feelings of oceanic boundlessness and secondly with visionary restructuralization. CONCLUSIONS Psilocybin generates profound alterations at both the brain and the experiential levels. We suggest that the brain's tendency to enter a hyperconnected-hyperarousal pattern under psilocybin represents the potential to entertain variant mental associations. These findings illuminate the intricate interplay between brain dynamics and subjective experience under psilocybin, thereby providing insights into the neurophysiology and neuroexperiential qualities of the psychedelic state.
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Affiliation(s)
- Sepehr Mortaheb
- Physiology of Cognition, GIGA Research, CRC Human Imaging Unit, University of Liège, Liège, Belgium; Fund for Scientific Research FNRS, Brussels, Belgium
| | - Larry D Fort
- Physiology of Cognition, GIGA Research, CRC Human Imaging Unit, University of Liège, Liège, Belgium; Fund for Scientific Research FNRS, Brussels, Belgium
| | - Natasha L Mason
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Pablo Mallaroni
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Johannes G Ramaekers
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands.
| | - Athena Demertzi
- Physiology of Cognition, GIGA Research, CRC Human Imaging Unit, University of Liège, Liège, Belgium; Fund for Scientific Research FNRS, Brussels, Belgium; Psychology & Neuroscience of Cognition, University of Liège, Liège, Belgium.
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Iorgu AM, Vasilescu AN, Pfeiffer N, Spanagel R, Mallien AS, Inta D, Gass P. Psilocybin does not induce the vulnerability marker HSP70 in neurons susceptible to Olney's lesions. Eur Arch Psychiatry Clin Neurosci 2024; 274:1013-1019. [PMID: 37934233 PMCID: PMC11127870 DOI: 10.1007/s00406-023-01699-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 10/02/2023] [Indexed: 11/08/2023]
Abstract
S-ketamine, a N-methyl-D-aspartate receptor (NMDAR) antagonist, and psilocybin, a 5-hydroxy-tryptamine (serotonin) 2A receptor (5-HT2AR) agonist, are reported as effective rapid-acting antidepressants. Both compounds increase glutamate signalling and evoke cortical hyperexcitation. S-ketamine induces neurotoxicity especially in the retrosplenial cortex (Olney's lesions). Whether psilocybin produces similar neurotoxic effects has so far not been investigated. We performed an immunohistochemical whole-brain mapping for heat shock protein 70 (HSP70) in rats treated with psilocybin, S-ketamine, and MK-801. In contrast to S-ketamine- and MK-801-treated animals, we did not detect any HSP70-positive neurons in retrosplenial cortex of rats treated with psilocybin. Our results suggest that psilocybin might be safer for clinical use compared to S-ketamine regarding neuronal damage.
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Affiliation(s)
- Ana-Maria Iorgu
- Department of Psychiatry and Psychotherapy, Research Group Animal Models in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, J5, 68159, Mannheim, Germany.
| | - Andrei-Nicolae Vasilescu
- Department of Psychiatry and Psychotherapy, Research Group Animal Models in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, J5, 68159, Mannheim, Germany
| | - Natascha Pfeiffer
- Department of Psychiatry and Psychotherapy, Research Group Animal Models in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, J5, 68159, Mannheim, Germany
| | - Rainer Spanagel
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Anne Stephanie Mallien
- Department of Psychiatry and Psychotherapy, Research Group Animal Models in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, J5, 68159, Mannheim, Germany
| | - Dragos Inta
- Department for Community Health, Faculty of Natural Sciences and Medicine, University of Fribourg, Fribourg, Switzerland
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Peter Gass
- Department of Psychiatry and Psychotherapy, Research Group Animal Models in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, J5, 68159, Mannheim, Germany
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Haniff ZR, Bocharova M, Mantingh T, Rucker JJ, Velayudhan L, Taylor DM, Young AH, Aarsland D, Vernon AC, Thuret S. Psilocybin for dementia prevention? The potential role of psilocybin to alter mechanisms associated with major depression and neurodegenerative diseases. Pharmacol Ther 2024; 258:108641. [PMID: 38583670 DOI: 10.1016/j.pharmthera.2024.108641] [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: 09/05/2023] [Revised: 03/28/2024] [Accepted: 04/02/2024] [Indexed: 04/09/2024]
Abstract
Major depression is an established risk factor for subsequent dementia, and depression in late life may also represent a prodromal state of dementia. Considering current challenges in the clinical development of disease modifying therapies for dementia, the focus of research is shifting towards prevention and modification of risk factors to alter the neurodegenerative disease trajectory. Understanding mechanistic commonalities underlying affective symptoms and cognitive decline may reveal biomarkers to aid early identification of those at risk of progressing to dementia during the preclinical phase of disease, thus allowing for timely intervention. Adult hippocampal neurogenesis (AHN) is a phenomenon that describes the birth of new neurons in the dentate gyrus throughout life and it is associated with spatial learning, memory and mood regulation. Microglia are innate immune system macrophages in the central nervous system that carefully regulate AHN via multiple mechanisms. Disruption in AHN is associated with both dementia and major depression and microgliosis is a hallmark of several neurodegenerative diseases. Emerging evidence suggests that psychedelics promote neuroplasticity, including neurogenesis, and may also be immunomodulatory. In this context, psilocybin, a serotonergic agonist with rapid-acting antidepressant properties has the potential to ameliorate intersecting pathophysiological processes relevant for both major depression and neurodegenerative diseases. In this narrative review, we focus on the evidence base for the effects of psilocybin on adult hippocampal neurogenesis and microglial form and function; which may suggest that psilocybin has the potential to modulate multiple mechanisms of action, and may have implications in altering the progression from major depression to dementia in those at risk.
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Affiliation(s)
- Zarah R Haniff
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom.
| | - Mariia Bocharova
- Department of Old Age Psychiatry, Division of Academic Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom
| | - Tim Mantingh
- Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom
| | - James J Rucker
- Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom; South London and Maudsley NHS Foundation Trust, Maudsley Hospital, Denmark Hill, London, United Kingdom
| | - Latha Velayudhan
- Department of Old Age Psychiatry, Division of Academic Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom
| | - David M Taylor
- South London and Maudsley NHS Foundation Trust, Maudsley Hospital, Denmark Hill, London, United Kingdom
| | - Allan H Young
- Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom; South London and Maudsley NHS Foundation Trust, Bethlem Royal Hospital, Monks Orchard Road, Beckenham, Kent, United Kingdom
| | - Dag Aarsland
- Department of Old Age Psychiatry, Division of Academic Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom; Wolfson Centre for Age Related Diseases, Division of Neuroscience of the Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom; Stavanger University Hospital, Stavanger, Norway
| | - Anthony C Vernon
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom; MRC Centre for Neurodevelopmental Disorders, King's College London, United Kingdom.
| | - Sandrine Thuret
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom.
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Lasch A, Schweikert T, Dora E, Kolb T, Schurig HL, Walther A. [Psilocybin-Assisted Treatment of Depression, Anxiety and Substance use Disorders: Neurobiological Basis and Clinical Application]. FORTSCHRITTE DER NEUROLOGIE-PSYCHIATRIE 2024; 92:230-245. [PMID: 37207669 DOI: 10.1055/a-2046-5202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Successful therapy of mental disorders is very important in view of the high level of suffering of those affected. Since established pharmaceutical and psychotherapeutic approaches do not lead to the desired improvement in all cases, complementary or alternative treatment methods are intensively researched. Psilocybin-assisted psychotherapy seems particularly promising, and has been approved in the USA for larger clinical trials. Psilocybin belongs to the group of psychedelics and influences psychological experiences. In assisted therapy, psilocybin is administered in controlled doses under medical supervision to patients with different mental disorders. In the studies conducted so far, longer-term positive effects could be shown after just one or a few doses. In order to provide a better understanding of the potential therapeutic mechanisms, this article will first describe neurobiological and psychological effects of psilocybin. To better assess the potential of psilocybin-assisted psychotherapy for various disorders, clinical studies conducted so far with patients administered psilocybin are reviewed.
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Affiliation(s)
- Anna Lasch
- Biopsychologie, Technische Universität Dresden, Dresden, Germany
| | - Timo Schweikert
- Psychotherapie und Systemneurowissenschaften, Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Eva Dora
- Biopsychologie, Technische Universität Dresden, Dresden, Germany
| | - Theresa Kolb
- Universitätsklinikum Carl Gustav Carus Dresden, Division Psychological and Social Medicine and Developmental Neuroscience, Dresden, Germany
| | - Hanne Lilian Schurig
- Universitätsklinikum Carl Gustav Carus Dresden, Division Psychological and Social Medicine and Developmental Neuroscience, Dresden, Germany
| | - Andreas Walther
- Klinische Psychologie und Psychotherapie, Universität Zürich Psychologisches Institut, Zurich, Switzerland
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Wolff M, Evens R, Mertens LJ, Schmidt C, Beck J, Rutrecht H, Cherniak AD, Gründer G, Jungaberle H. Measuring psychotherapeutic processes in the context of psychedelic experiences: Validation of the General Change Mechanisms Questionnaire (GCMQ). J Psychopharmacol 2024; 38:432-457. [PMID: 38742761 PMCID: PMC11102652 DOI: 10.1177/02698811241249698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
BACKGROUND Therapeutic and salutogenic effects of psychedelic drugs have been attributed to psychotherapeutic or psychotherapy-like processes that can unfold during the acute psychedelic experience and beyond. Currently, there are no psychometric instruments available to comprehensively assess psychotherapeutic processes (as conceptualized by empirical psychotherapy research) in the context of psychedelic experiences. AIMS We report the initial validation of the General Change Mechanisms Questionnaire (GCMQ), a self-report instrument designed to measure five empirically established general change mechanisms (GCMs) of psychotherapy-(1) resource activation, (2) therapeutic relationship, (3) problem actuation, (4) clarification, and (5) mastery-in the context of psychedelic experiences. METHODS An online survey in a sample of 1153 English-speaking and 714 German-speaking psychedelic users was conducted to evaluate simultaneously developed English- and German-language versions of the GCMQ. RESULTS The theory-based factor structure was confirmed. The five GCMQ scales showed good internal consistency. Evidence for convergent validity with external measures was obtained. Significant associations with different settings and with therapeutic, hedonic, and escapist use motives confirmed the hypothesized context dependence of GCM-related psychedelic experiences. Indicating potential therapeutic effects, the association between cumulative stressful life events and well-being was significantly moderated by resource activation, clarification, and mastery. Factor mixture modeling revealed five distinct profiles of GCM-related psychedelic experiences. CONCLUSION Initial testing indicates that the GCMQ is a valid and reliable instrument that can be used in future clinical and nonclinical psychedelic research. The five identified profiles of GCM-related experiences may be relevant to clinical uses of psychedelics and psychedelic harm reduction.
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Affiliation(s)
- Max Wolff
- Department of Psychiatry and Neurosciences, Charité—Universitätsmedizin Berlin, Campus Charité Mitte, Berlin, Germany
- MIND Foundation, Berlin, Germany
| | - Ricarda Evens
- Department of Psychiatry and Neurosciences, Charité—Universitätsmedizin Berlin, Campus Charité Mitte, Berlin, Germany
- Department of Psychology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Lea J Mertens
- Department of Molecular Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | | | - Jessica Beck
- MIND Foundation, Berlin, Germany
- Faculty of Psychology, Technische Universität Dresden, Dresden, Germany
| | | | - Aaron D Cherniak
- Department of Psychology, Stockholm University, Stockholm, Sweden
- Department of Psychology, Reichman University, Herzliya, Israel
| | - Gerhard Gründer
- Department of Molecular Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
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Erritzoe D, Barba T, Spriggs MJ, Rosas FE, Nutt DJ, Carhart-Harris R. Effects of discontinuation of serotonergic antidepressants prior to psilocybin therapy versus escitalopram for major depression. J Psychopharmacol 2024; 38:458-470. [PMID: 38520045 PMCID: PMC11102650 DOI: 10.1177/02698811241237870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/25/2024]
Abstract
BACKGROUND There is growing evidence for the therapeutic effects of the psychedelic drug psilocybin for major depression. However, due to the lack of safety data on combining psilocybin with selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) and concerns that there may be a negative interaction on efficacy, participants enrolling in psychedelic trials are usually required to discontinue SNRI/SNRIs prior to enrolling. AIMS Using data from a recent clinical trial examining the comparative efficacy the psychedelic drug psilocybin (P) combined with approximately 20 h of psychological support to a 6-week (daily) course of the SSRI escitalopram plus matched psychological support for major depressive disorder, we explored the effects of discontinuing SSRI/SNRIs prior to study enrolment on study outcomes. METHODS Exploratory post hoc analyses using linear mixed effects model were performed to investigate the discontinuation effect on various validated depression symptom severity scales and well-being. The impact of SSRI/SNRIs discontinuation on the acute psychedelic experience was also explored. RESULTS/OUTCOMES In the psilocybin group, there was a reduced treatment effect on all outcome measures for SSRI/SNRIs discontinuers compared with unmedicated patients at trial entry. However, no effects of discontinuation on measures of the acute psychedelic experience were found. CONCLUSION Discontinuation of SSRI/SNRIs before psilocybin might diminish response to treatment; however, as we did not test SSRI/SNRI continuation in our trial, we cannot infer such causation. Moreover, the exploratory nature of the analyses makes them hypothesis generating, and not confirmatory. A controlled trial of SSRI/SNRI discontinuation versus continuation prior to psilocybin is urgently required.
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Affiliation(s)
- David Erritzoe
- Division of Psychiatry, Department Brain Sciences, Centre for Psychedelic Research, Imperial College London, London, UK
| | - Tommaso Barba
- Division of Psychiatry, Department Brain Sciences, Centre for Psychedelic Research, Imperial College London, London, UK
| | - Meg J Spriggs
- Division of Psychiatry, Department Brain Sciences, Centre for Psychedelic Research, Imperial College London, London, UK
| | - Fernando E Rosas
- Division of Psychiatry, Department Brain Sciences, Centre for Psychedelic Research, Imperial College London, London, UK
- Department of Informatics, University of Sussex, Brighton, UK
| | - David J Nutt
- Division of Psychiatry, Department Brain Sciences, Centre for Psychedelic Research, Imperial College London, London, UK
| | - Robin Carhart-Harris
- Division of Psychiatry, Department Brain Sciences, Centre for Psychedelic Research, Imperial College London, London, UK
- Departments of Neurology and Psychiatry, University of California San Francisco, San Francisco, CA, USA
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Bellman V. Review of Psilocybin Use for Depression among Cancer Patients after Approval in Oregon. Cancers (Basel) 2024; 16:1702. [PMID: 38730654 PMCID: PMC11083170 DOI: 10.3390/cancers16091702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 04/25/2024] [Accepted: 04/25/2024] [Indexed: 05/13/2024] Open
Abstract
Despite the legalization of psilocybin therapy for depression in terminal illnesses such as advanced cancer through Oregon's Measure 109 in 2020, significant challenges have impeded its implementation. This review synthesizes the empirical data supporting the utilization of psilocybin therapy for addressing cancer-related depression, including an evaluation of its purported benefits and potential adverse effects. It provides a comprehensive examination of therapeutic strategies, dosing regimens, and barriers to ensuring responsible and equitable access. Salient issues explored include the development of ethical protocols, integration within healthcare systems, ensuring statewide availability, resolving legal ambiguities, and defining clinical standards. Oregon's pioneering role serves as a case study, highlighting the necessity of addressing regulatory, logistical, and ethical obstacles to ensure the establishment of rigorous and equitable psilocybin care models.
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Affiliation(s)
- Val Bellman
- Psychiatry Residency Training Program, University of Missouri Kansas City, Kansas City, MO 64108, USA
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Maia JM, de Oliveira BSA, Branco LGS, Soriano RN. Therapeutic potential of psychedelics: History, advancements, and unexplored frontiers. Prog Neuropsychopharmacol Biol Psychiatry 2024; 131:110951. [PMID: 38307161 DOI: 10.1016/j.pnpbp.2024.110951] [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] [Received: 10/24/2023] [Revised: 12/20/2023] [Accepted: 01/18/2024] [Indexed: 02/04/2024]
Abstract
Psychedelics (serotonergic hallucinogens) are psychoactive substances that can alter perception and mood, and affect cognitive functions. These substances activate 5-HT2A receptors and may exert therapeutic effects. Some of the disorders for which psychedelic-assisted therapy have been studied include depression, addiction, anxiety and post-traumatic stress disorder. Despite the increasing number of studies reporting clinical effectiveness, with fewer negative symptoms and, additionally, minimal side effects, questions remain to be explored in the field of psychedelic medicine. Although progress has been achieved, there is still little understanding of the relationship among human brain and the modulation induced by these drugs. The present article aimed to describe, review and highlight the most promising findings in the literature regarding the (putative) therapeutic effects of psychedelics.
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Affiliation(s)
- Juliana Marino Maia
- Department of Medicine, Federal University of Juiz de Fora, Governador Valadares, MG 35032-620, Brazil
| | | | - Luiz G S Branco
- Department of Basic and Oral Biology, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP 14040-904, Brazil; Department of Physiology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP 14040-900, Brazil.
| | - Renato Nery Soriano
- Division of Physiology and Biophysics, Department of Basic Life Sciences, Federal University of Juiz de Fora, Governador Valadares, MG 35020-360, Brazil
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Sloshower J, Zeifman RJ, Guss J, Krause R, Safi-Aghdam H, Pathania S, Pittman B, D'Souza DC. Psychological flexibility as a mechanism of change in psilocybin-assisted therapy for major depression: results from an exploratory placebo-controlled trial. Sci Rep 2024; 14:8833. [PMID: 38632313 PMCID: PMC11024097 DOI: 10.1038/s41598-024-58318-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 03/27/2024] [Indexed: 04/19/2024] Open
Abstract
Several phase II studies have demonstrated that psilocybin-assisted therapy shows therapeutic potential across a spectrum of neuropsychiatric conditions, including major depressive disorder (MDD). However, the mechanisms underlying its often persisting beneficial effects remain unclear. Observational research suggests that improvements in psychological flexibility may mediate therapeutic effects. However, no psychedelic trials to date have substantiated this finding in a clinical sample. In an exploratory placebo-controlled, within-subject, fixed-order study, individuals with moderate to severe MDD were administered placebo (n = 19) followed by psilocybin (0.3 mg/kg) (n = 15) 4 weeks later. Dosing sessions were embedded within a manualized psychotherapy that incorporated principles of Acceptance and Commitment Therapy. Depression severity, psychological flexibility, mindfulness, and values-congruent living were measured over a 16-weeks study period. Psychological flexibility, several facets of mindfulness, and values-congruent living significantly improved following psilocybin and were maintained through week 16. Additionally, improvements in psychological flexibility and experiential acceptance were strongly associated with reductions in depression severity following psilocybin. These findings support the theoretical premise of integrating psilocybin treatment with psychotherapeutic platforms that target psychological flexibility and add to emerging evidence that increasing psychological flexibility may be an important putative mechanism of change in psilocybin-assisted therapy for MDD and potentially, other mental health conditions.
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Affiliation(s)
- Jordan Sloshower
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA.
- Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA.
- West Rock Wellness PLLC, New Haven, CT, USA.
| | - Richard J Zeifman
- NYU Langone Center for Psychedelic Medicine, NYU Grossman School of Medicine, New York, NY, USA
- Centre for Psychedelic Research, Division of Psychiatry, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - Jeffrey Guss
- Department of Psychiatry, NYU Grossman School of Medicine, New York, NY, USA
| | - Robert Krause
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Yale School of Nursing, New Haven, CT, USA
- Centered PLLC, New Haven, CT, USA
| | - Hamideh Safi-Aghdam
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Surbhi Pathania
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Brian Pittman
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Deepak Cyril D'Souza
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA
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Wood ME, Brown GJ, Karschner EL, Seither JZ, Brown JT, Knittel JL, Walterscheid JP. Screening and confirmation of psilocin, mitragynine, phencyclidine, ketamine and ketamine metabolites by liquid chromatography-tandem mass spectrometry. J Anal Toxicol 2024; 48:111-118. [PMID: 38287693 DOI: 10.1093/jat/bkae002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/10/2024] [Accepted: 01/22/2024] [Indexed: 01/31/2024] Open
Abstract
A safe and productive workplace requires a sober workforce, free from substances that impair judgment and concentration. Although drug monitoring programs already exist, the scope and loopholes of standard workplace testing panels are well known, allowing other substances to remain a source of risk. Therefore, a high-throughput urine screening method for psilocin, mitragynine, phencyclidine, ketamine, norketamine and dehydronorketamine was developed and validated in conjunction with a urine and blood confirmation method. There are analytical challenges to overcome with psilocin and mitragynine, particularly when it comes to drug stability and unambiguous identification in authentic specimens. Screening and confirmation methods were validated according to the American National Standards Institute/Academy Standards Board (ANSI/ASB) Standard 036, Standard Practices for Method Validation in Forensic Toxicology. An automated liquid handling system equipped with dispersive pipette extraction tips was utilized for preparing screening samples, whereas an offline solid-phase extraction method was used for confirmation sample preparation. Both methods utilized liquid chromatography-tandem mass spectrometry to achieve limits of detection between 1-5 ng/mL for the screening method and 1 ng/mL for the confirmation method. Automation allows for faster throughput and enhanced quality assurance, which improves turnaround time. Compared to previous in-house methods, specimen volumes were substantially decreased for both blood and urine, which is an advantage when volume is limited. This screening technique is well suited for evaluating large numbers of specimens from those employed in safety-sensitive workforce positions. This method can be utilized by workplace drug testing, human performance and postmortem laboratories seeking robust qualitative screening and confirmation methods for analytes that have traditionally been challenging to routinely analyze.
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Affiliation(s)
- Madeleine E Wood
- Division of Forensic Toxicology, Armed Forces Medical Examiner System, 115 Purple Heart Dr., Dover AFB, DE 19902, USA
| | - Glenna J Brown
- Division of Forensic Toxicology, Armed Forces Medical Examiner System, 115 Purple Heart Dr., Dover AFB, DE 19902, USA
| | - Erin L Karschner
- Division of Forensic Toxicology, Armed Forces Medical Examiner System, 115 Purple Heart Dr., Dover AFB, DE 19902, USA
| | - Joshua Z Seither
- Division of Forensic Toxicology, Armed Forces Medical Examiner System, 115 Purple Heart Dr., Dover AFB, DE 19902, USA
| | - Jordan T Brown
- Division of Forensic Toxicology, Armed Forces Medical Examiner System, 115 Purple Heart Dr., Dover AFB, DE 19902, USA
| | - Jessica L Knittel
- Division of Forensic Toxicology, Armed Forces Medical Examiner System, 115 Purple Heart Dr., Dover AFB, DE 19902, USA
| | - Jeffrey P Walterscheid
- Division of Forensic Toxicology, Armed Forces Medical Examiner System, 115 Purple Heart Dr., Dover AFB, DE 19902, USA
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12
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Frautschi PC, Singh AP, Stowe NA, Yu JPJ. Multimodal Neuroimaging of the Effect of Serotonergic Psychedelics on the Brain. AJNR Am J Neuroradiol 2024; 45:ajnr.A8118. [PMID: 38360790 DOI: 10.3174/ajnr.a8118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 11/20/2023] [Indexed: 02/17/2024]
Abstract
The neurobiological mechanisms underpinning psychiatric disorders such as treatment-resistant major depression, post-traumatic stress disorder, and substance use disorders, remain unknown. Psychedelic compounds, such as psilocybin, lysergic acid diethylamide, and N,N-dimethyltryptamine, have emerged as potential therapies for these disorders because of their hypothesized ability to induce neuroplastic effects and alter functional networks in the brain. Yet, the mechanisms underpinning the neurobiological treatment response remain obscure. Quantitative neuroimaging is uniquely positioned to provide insight into the neurobiological mechanisms of these emerging therapies and quantify the patient treatment response. This review aims to synthesize our current state-of-the-art understanding of the functional changes occurring in the brain following psilocybin, lysergic acid diethylamide, or N,N-dimethyltryptamine administration in human participants with fMRI and PET. We further aim to disseminate our understanding of psychedelic compounds as they relate to neuroimaging with the goal of improved diagnostics and treatment of neuropsychiatric illness.
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Affiliation(s)
- Paloma C Frautschi
- Department of Radiology (P.C.F., A.P.S., J.-P.J.Y.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Ajay P Singh
- Department of Radiology (P.C.F., A.P.S., J.-P.J.Y.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
- Graduate Program in Cellular and Molecular Biology (A.P.S., J.-P.J.Y.), University of Wisconsin-Madison, Madison, Wisconsin
| | - Nicholas A Stowe
- Neuroscience Training Program, Wisconsin Institutes for Medical Research (N.A.S., J.-P.J.Y.), University of Wisconsin-Madison, Madison, Wisconsin
| | - John-Paul J Yu
- Department of Radiology (P.C.F., A.P.S., J.-P.J.Y.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
- Neuroscience Training Program, Wisconsin Institutes for Medical Research (N.A.S., J.-P.J.Y.), University of Wisconsin-Madison, Madison, Wisconsin
- Graduate Program in Cellular and Molecular Biology (A.P.S., J.-P.J.Y.), University of Wisconsin-Madison, Madison, Wisconsin
- Department of Biomedical Engineering (J.-P.J.Y.), University of Wisconsin-Madison, Madison, Wisconsin
- Department of Psychiatry (J.-P.J.Y.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
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13
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Timmermann C, Zeifman RJ, Erritzoe D, Nutt DJ, Carhart-Harris RL. Effects of DMT on mental health outcomes in healthy volunteers. Sci Rep 2024; 14:3097. [PMID: 38326357 PMCID: PMC10850177 DOI: 10.1038/s41598-024-53363-y] [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: 05/09/2023] [Accepted: 01/30/2024] [Indexed: 02/09/2024] Open
Abstract
Psilocybin, a serotonergic psychedelic, is being increasingly researched in clinical studies for the treatment of psychiatric disorders. The relatively lengthy duration of oral psilocybin's acute effects (4-6 h) may have pragmatic and cost-effectiveness limitations. Here, we explored the effects of intravenous (IV) N,N-Dimethyltryptamine (DMT), a closely related, but faster-acting psychedelic intervention, on mental health outcomes in healthy volunteers. Data is reported from two separate analyses: (1) A comparison of mental health-related variables 1 week after 7, 14, 18, and 20 mg of IV DMT versus IV saline placebo (n = 13) and, (2) A prospective dataset assessing effects before versus 2 weeks after 20 mg of IV DMT (n = 17). Mental health outcomes included measures of depression severity (QIDS-SR16), trait anxiety (STAI-T), Neuroticism (NEO-FFI), wellbeing (WHO-5), meaning in life (MLQ), optimism (LOT-R), and gratitude (GQ-6). In both the prospective and placebo-controlled datasets, significant improvements in scores of depression were found 1-2 weeks after DMT administration. Significant reductions in trait Neuroticism were only found for the placebo-controlled sample. Finally, changes in depression and trait anxiety correlated with acute peak experiences (assessed via 'Oceanic Boundlessness'). While the use of two separate cohorts in pooled analysis limits the generalizability of these correlational findings, these results suggest that DMT may reduce depressive symptomatology by inducing peak experiences. The short half-life of IV DMT and its potential for flexible dosing via controlled infusions makes it an appealing candidate for psychedelic medicine. Further research in clinical samples is needed to corroborate the therapeutic potential of DMT.
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Affiliation(s)
- Christopher Timmermann
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, UK.
| | - Richard J Zeifman
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, UK
- NYU Langone Center for Psychedelic Medicine, NYU Grosssman School of Medicine, New York, USA
| | - David Erritzoe
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - David J Nutt
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, UK
- Centre for Psychiatry, Division of Brain Sciences, Faculty of Medicine, Imperial College, London, UK
| | - Robin L Carhart-Harris
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, UK
- Psychedelics Division, Neuroscape, Department of Neurology, University of California, San Francisco, USA
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14
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Barba T, Kettner H, Radu C, Peill JM, Roseman L, Nutt DJ, Erritzoe D, Carhart-Harris R, Giribaldi B. Psychedelics and sexual functioning: a mixed-methods study. Sci Rep 2024; 14:2181. [PMID: 38326446 PMCID: PMC10850066 DOI: 10.1038/s41598-023-49817-4] [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: 05/16/2023] [Accepted: 12/12/2023] [Indexed: 02/09/2024] Open
Abstract
Do psychedelics affect sexual functioning postacutely? Anecdotal and qualitative evidence suggests they do, but this has never been formally tested. While sexual functioning and satisfaction are generally regarded as an important aspect of human wellbeing, sexual dysfunction is a common symptom of mental health disorders. It is also a common side effect of selective serotonin reuptake inhibitors (SSRIs), a first line treatment for depression. The aim of the present paper was to investigate the post-acute effects of psychedelics on self-reported sexual functioning, combining data from two independent studies, one large and naturalistic and the other a smaller but controlled clinical trial. Naturalistic use of psychedelics was associated with improvements in several facets of sexual functioning and satisfaction, including improved pleasure and communication during sex, satisfaction with one's partner and physical appearance. Convergent results were found in a controlled trial of psilocybin therapy versus an SSRI, escitalopram, for depression. In this trial, patients treated with psilocybin reported positive changes in sexual functioning after treatment, while patients treated with escitalopram did not. Despite focusing on different populations and settings, this is the first research study to quantitively investigate the effects of psychedelics on sexual functioning. Results imply a potential positive effect on post-acute sexual functioning and highlight the need for more research on this.
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Affiliation(s)
- Tommaso Barba
- Department of Medicine, Centre for Psychedelic Research, Imperial College London, London, UK.
| | - Hannes Kettner
- Department of Medicine, Centre for Psychedelic Research, Imperial College London, London, UK
- Psychedelics Division, Neuroscape, Department of Neurology, University of California San Francisco, San Francisco, United States
| | - Caterina Radu
- Department of Medicine, Centre for Psychedelic Research, Imperial College London, London, UK
| | - Joseph M Peill
- Department of Medicine, Centre for Psychedelic Research, Imperial College London, London, UK
| | - Leor Roseman
- Department of Medicine, Centre for Psychedelic Research, Imperial College London, London, UK
| | - David J Nutt
- Department of Medicine, Centre for Psychedelic Research, Imperial College London, London, UK
| | - David Erritzoe
- Department of Medicine, Centre for Psychedelic Research, Imperial College London, London, UK
| | - Robin Carhart-Harris
- Department of Medicine, Centre for Psychedelic Research, Imperial College London, London, UK
- Psychedelics Division, Neuroscape, Department of Neurology, University of California San Francisco, San Francisco, United States
| | - Bruna Giribaldi
- Department of Medicine, Centre for Psychedelic Research, Imperial College London, London, UK
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Hovmand OR, Ebbesen Jensen M, Søgaard Juul T, Korsbak Madsen M, MacDonald Fisher P, Siggaard Stenbæk D. Validation of the Danish Translation of the Revised Mystical Experience Questionnaire (MEQ30) and Possible Impact of Setting, Dose and Intention. J Psychoactive Drugs 2024:1-10. [PMID: 38225795 DOI: 10.1080/02791072.2024.2302186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 12/06/2023] [Indexed: 01/17/2024]
Abstract
Research suggests positive changes in both well-being and psychiatric symptoms following a psychedelic experience. One explanation may be the ability of psychedelic compounds to occasion mystical-type experiences. The Revised Mystical Experiences Questionnaire (MEQ30) is designed to assess the intensity and quality of such experiences. We examined the validity, reliability, and factor structure of a Danish translation of the MEQ30 in one sample of healthy volunteers receiving psilocybin in a laboratory setting (N = 47) and two samples of recreative users of psychedelics, in which MEQ30 was reported retrospectively through an online survey based on their most recent experience with psilocybin (N = 834) or their most memorable experience with any psychedelic (N = 500). We conducted a confirmatory factor analysis of the previously suggested factor structures, calculated alpha and omega, and tested the associations between MEQ30 total score and setting, intention and dose. We found excellent internal reliability estimates across all samples, and confirmatory factor analysis showed that a four-factor structure, had the best, fair fit to the data. We further found that the MEQ30 total score was correlated with dose and a spiritual/religious intention, but not with setting. The Danish MEQ30 seems to be a valid tool for accessing mystical-type experiences among Danish-speaking individuals.
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Affiliation(s)
- Oliver Rumle Hovmand
- Psychiatry South, Region Zealand Psychiatry, Vordingborg, Denmark
- Psychiatric Research Unit, Region Zealand Psychiatry, Slagelse, Denmark
- Neurobiological Research Unit, Copenhagen University Hospital, Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Mathias Ebbesen Jensen
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
- Psychiatric Centre Copenhagen, Copenhagen University Hospital, Copenhagen, Denmark
| | - Tobias Søgaard Juul
- Psychiatric Centre Copenhagen, Copenhagen University Hospital, Copenhagen, Denmark
| | - Martin Korsbak Madsen
- Neurobiological Research Unit, Copenhagen University Hospital, Copenhagen, Denmark
- Department of Psychiatry Svendborg, Svendborg, Denmark
| | - Patrick MacDonald Fisher
- Neurobiological Research Unit, Copenhagen University Hospital, Copenhagen, Denmark
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Dea Siggaard Stenbæk
- Neurobiological Research Unit, Copenhagen University Hospital, Copenhagen, Denmark
- Department of Psychology, University of Copenhagen, Copenhagen, Denmark
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16
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Madsen MK, Petersen AS, Stenbaek DS, Sørensen IM, Schiønning H, Fjeld T, Nykjaer CH, Larsen SMU, Grzywacz M, Mathiesen T, Klausen IL, Overgaard-Hansen O, Brendstrup-Brix K, Linnet K, Johansen SS, Fisher PM, Jensen RH, Knudsen GM. CCH attack frequency reduction after psilocybin correlates with hypothalamic functional connectivity. Headache 2024; 64:55-67. [PMID: 38238974 DOI: 10.1111/head.14656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 09/11/2023] [Accepted: 09/24/2023] [Indexed: 01/23/2024]
Abstract
OBJECTIVE To evaluate the feasibility and prophylactic effect of psilocybin as well as its effects on hypothalamic functional connectivity (FC) in patients with chronic cluster headache (CCH). BACKGROUND CCH is an excruciating and difficult-to-treat disorder with incompletely understood pathophysiology, although hypothalamic dysfunction has been implicated. Psilocybin may have beneficial prophylactic effects, but clinical evidence is limited. METHODS In this small open-label clinical trial, 10 patients with CCH were included and maintained headache diaries for 10 weeks. Patients received three doses of peroral psilocybin (0.14 mg/kg) on the first day of weeks five, six, and seven. The first 4 weeks served as baseline and the last 4 weeks as follow-up. Hypothalamic FC was determined using functional magnetic resonance imaging the day before the first psilocybin dose and 1 week after the last dose. RESULTS The treatment was well tolerated. Attack frequency was reduced by mean (standard deviation) 31% (31) from baseline to follow-up (pFWER = 0.008). One patient experienced 21 weeks of complete remission. Changes in hypothalamic-diencephalic FC correlated negatively with a percent change in attack frequency (pFWER = 0.03, R = -0.81), implicating this neural pathway in treatment response. CONCLUSION Our results indicate that psilocybin may have prophylactic potential and implicates the hypothalamus in possible treatment response. Further clinical studies are warranted.
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Affiliation(s)
- Martin K Madsen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Department of Neurology, Odense University Hospital, Odense, Denmark
| | - Anja Sofie Petersen
- Danish Headache Center, Department of Neurology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Dea S Stenbaek
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Department of Psychology, University of Copenhagen, Copenhagen, Denmark
| | - Inger Marie Sørensen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Harald Schiønning
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Tobias Fjeld
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Charlotte H Nykjaer
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Sara Marie Ulv Larsen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Maria Grzywacz
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Tobias Mathiesen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Ida L Klausen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Oliver Overgaard-Hansen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | | | - Kristian Linnet
- Department of Forensic Medicine, Section of Forensic Chemistry, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sys S Johansen
- Department of Forensic Medicine, Section of Forensic Chemistry, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Patrick M Fisher
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Rigmor H Jensen
- Danish Headache Center, Department of Neurology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gitte M Knudsen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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17
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Weiss B, Ginige I, Shannon L, Giribaldi B, Murphy-Beiner A, Murphy R, Baker-Jones M, Martell J, Nutt DJ, Carhart-Harris RL, Erritzoe D. Personality change in a trial of psilocybin therapy v. escitalopram treatment for depression. Psychol Med 2024; 54:178-192. [PMID: 37264814 PMCID: PMC10692311 DOI: 10.1017/s0033291723001514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
BACKGROUND Psilocybin Therapy (PT) is being increasingly studied as a psychiatric intervention. Personality relates to mental health and can be used to probe the nature of PT's therapeutic action. METHODS In a phase 2, double-blind, randomized, active comparator controlled trial involving patients with moderate-to-severe major depressive disorder, we compared psilocybin with escitalopram, over a core 6-week trial period. Five-Factor model personality domains, Big Five Aspect Scale Openness aspects, Absorption, and Impulsivity were measured at Baseline, Week 6, and Month 6 follow-up. RESULTS PT was associated with decreases in neuroticism (B = -0.63), introversion (B = -0.38), disagreeableness (B = -0.47), impulsivity (B = -0.40), and increases in absorption (B = 0.32), conscientiousness (B = 0.30), and openness (B = 0.23) at week 6, with neuroticism (B = -0.47) and disagreeableness (B = -0.41) remaining decreased at month 6. Escitalopram Treatment (ET) was associated with decreases in neuroticism (B = -0.38), disagreeableness (B = -0.26), impulsivity (B = -0.35), and increases in openness (B = 0.28) at week 6, with neuroticism (B = -0.46) remaining decreased at month 6. No significant between-condition differences were observed. CONCLUSIONS Personality changes across both conditions were in a direction consistent with improved mental health. With the possible exception of trait absorption, there were no compelling between-condition differences warranting conclusions regarding a selective action of PT (v. ET) on personality; however, post-ET changes in personality were significantly moderated by pre-trial positive expectancy for escitalopram, whereas expectancy did not moderate response to PT.
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Affiliation(s)
- Brandon Weiss
- Centre for Psychedelic Research, Division of Academic Psychiatry, Imperial College London, London, UK
| | - Induni Ginige
- Centre for Psychedelic Research, Division of Academic Psychiatry, Imperial College London, London, UK
| | - Lu Shannon
- Centre for Psychedelic Research, Division of Academic Psychiatry, Imperial College London, London, UK
| | - Bruna Giribaldi
- Centre for Psychedelic Research, Division of Academic Psychiatry, Imperial College London, London, UK
| | - Ashleigh Murphy-Beiner
- Centre for Psychedelic Research, Division of Academic Psychiatry, Imperial College London, London, UK
| | - Roberta Murphy
- Centre for Psychedelic Research, Division of Academic Psychiatry, Imperial College London, London, UK
| | - Michelle Baker-Jones
- Centre for Psychedelic Research, Division of Academic Psychiatry, Imperial College London, London, UK
| | - Jonny Martell
- Centre for Psychedelic Research, Division of Academic Psychiatry, Imperial College London, London, UK
| | - David J. Nutt
- Centre for Psychedelic Research, Division of Academic Psychiatry, Imperial College London, London, UK
| | - Robin L. Carhart-Harris
- Centre for Psychedelic Research, Division of Academic Psychiatry, Imperial College London, London, UK
- Psychedelics Division, Neuroscape, Department of Neurology, University of California, San Francisco, CA, USA
| | - David Erritzoe
- Centre for Psychedelic Research, Division of Academic Psychiatry, Imperial College London, London, UK
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18
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Lynn SJ, McDonald CW, Sleight FG, Mattson RE. Cross-validation of the ego dissolution scale: implications for studying psychedelics. Front Neurosci 2023; 17:1267611. [PMID: 38116073 PMCID: PMC10729006 DOI: 10.3389/fnins.2023.1267611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 11/09/2023] [Indexed: 12/21/2023] Open
Abstract
Introduction Ego dissolution, variously called Ego-Loss, self-loss, and ego disintegration, is a hallmark of psychedelic drug use. We cross-validated the 10-item Ego Dissolution Scale, which we developed to assess ego dissolution in everyday life, and we included comparator variables that expanded our original assessment of construct validity. Methods Undergraduate college student volunteers (N = 527) completed the measures online. Results We replicated the original two factor structure (i.e., subfactors: Ego-Loss and Unity/connectedness with others, the world, universe), and we determined that the total score (Cronbach's α = 0.79) and subfactors (Ego-Loss = 78; Unity = 0.83) possessed adequate-to-good reliability and strong convergent validity (e.g., mindfulness, hallucination-predisposition, sleep variables, personality variables, positive/negative affect transliminality, dissociation/depersonalization), while neuroticism, social desirability did not correlate highly with ego dissolution. We identified distinct patterns of relations of measures associated with the Ego-Loss vs. Unity subfactors. Discussion We discuss the implications of the use of the EDS for studying everyday aspects of ego dissolution, the long-term effects of psychedelic use, and the value of using the scale in conjunction with measures of the acute effects of psychedelics.
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Affiliation(s)
- Steven Jay Lynn
- Psychology Department, Binghamton University, State University of New York, Binghamton, NY, United States
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19
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Holas P, Kamińska J. Mindfulness meditation and psychedelics: potential synergies and commonalities. Pharmacol Rep 2023; 75:1398-1409. [PMID: 37926796 PMCID: PMC10661803 DOI: 10.1007/s43440-023-00551-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/17/2023] [Accepted: 10/18/2023] [Indexed: 11/07/2023]
Abstract
There has been increasing scientific and clinical interest in studying psychedelic and meditation-based interventions in recent years, both in the context of improving mental health and as tools for understanding the mind. Several authors suggest neurophysiological and phenomenological parallels and overlaps between psychedelic and meditative states and suggest synergistic effects of both methods. Both psychedelic-assisted therapy and meditation training in the form of mindfulness-based interventions have been experimentally validated with moderate to large effects as alternative treatments for a variety of mental health problems, including depression, addictions, and anxiety disorders. Both demonstrated significant post-acute and long-term decreases in clinical symptoms and enhancements in well-being in healthy participants, in addition. Postulated shared salutogenic mechanisms, include, among others the ability to alter self-consciousness, present-moment awareness and antidepressant action via corresponding neuromodulatory effects. These shared mechanisms between mindfulness training and psychedelic intervention have led to scientists theorizing, and recently demonstrating, positive synergistic effects when both are used in combination. Research findings suggest that these two approaches can complement each other, enhancing the positive effects of both interventions. However, more theoretical accounts and methodologically sound research are needed before they can be extended into clinical practice. The current review aims to discuss the theoretical rationale of combining psychedelics with mindfulness training, including the predictive coding framework as well as research findings regarding synergies and commonalities between mindfulness training and psychedelic intervention. In addition, suggestions how to combine the two modalities are provided.
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Affiliation(s)
- Paweł Holas
- Faculty of Psychology, University of Warsaw, Warsaw, Poland.
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20
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Gattuso JJ, Wilson C, Hannan AJ, Renoir T. Psilocybin as a lead candidate molecule in preclinical therapeutic studies of psychiatric disorders: A systematic review. J Neurochem 2023. [PMID: 38019032 DOI: 10.1111/jnc.16017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 11/02/2023] [Accepted: 11/10/2023] [Indexed: 11/30/2023]
Abstract
Psilocybin is the main psychoactive compound found in hallucinogenic/magic mushrooms and can bind to both serotonergic and tropomyosin receptor kinase b (TrkB) receptors. Psilocybin has begun to show efficacy for a range of neuropsychiatric conditions, including treatment-resistant depression and anxiety disorders; however, neurobiological mechanisms are still being elucidated. Clinical research has found that psilocybin can alter functional connectivity patterns in human brains, which is often associated with therapeutic outcomes. However, preclinical research affords the opportunity to assess the potential cellular mechanisms by which psilocybin may exert its therapeutic effects. Preclinical rodent models can also facilitate a more tightly controlled experimental context and minimise placebo effects. Furthermore, where there is a rationale, preclinical researchers can investigate psilocybin administration in neuropsychiatric conditions that have not yet been researched clinically. As a result, we have systematically reviewed the knowledge base, identifying 82 preclinical studies which were screened based on specific criteria. This resulted in the exclusion of 44 articles, with 34 articles being included in the main review and another 2 articles included as Supporting Information materials. We found that psilocybin shows promise as a lead candidate molecule for treating a variety of neuropsychiatric conditions, albeit showing the most efficacy for depression. We discuss the experimental findings, and identify possible mechanisms whereby psilocybin could invoke therapeutic changes. Furthermore, we critically evaluate the between-study heterogeneity and possible future research avenues. Our review suggests that preclinical rodent models can provide valid and translatable tools for researching novel psilocybin-induced molecular and cellular mechanisms, and therapeutic outcomes.
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Affiliation(s)
- James J Gattuso
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia
| | - Carey Wilson
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia
- Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Victoria, Australia
| | - Thibault Renoir
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia
- Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Victoria, Australia
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Nayak SM, Jackson H, Sepeda ND, Mathai DS, So S, Yaffe A, Zaki H, Brasher TJ, Lowe MX, Jolly DRP, Barrett FS, Griffiths RR, Strickland JC, Johnson MW, Jackson H, Garcia-Romeu A. Naturalistic psilocybin use is associated with persisting improvements in mental health and wellbeing: results from a prospective, longitudinal survey. Front Psychiatry 2023; 14:1199642. [PMID: 37795509 PMCID: PMC10545967 DOI: 10.3389/fpsyt.2023.1199642] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 08/14/2023] [Indexed: 10/06/2023] Open
Abstract
Introduction The classic psychedelic psilocybin, found in some mushroom species, has received renewed interest in clinical research, showing potential mental health benefits in preliminary trials. Naturalistic use of psilocybin outside of research settings has increased in recent years, though data on the public health impact of such use remain limited. Methods This prospective, longitudinal study comprised six sequential automated web-based surveys that collected data from adults planning to take psilocybin outside clinical research: at time of consent, 2 weeks before, the day before, 1-3 days after, 2-4 weeks after, and 2-3 months after psilocybin use. Results A sample of 2,833 respondents completed all baseline assessments approximately 2 weeks before psilocybin use, 1,182 completed the 2-4 week post-use survey, and 657 completed the final follow-up survey 2-3 months after psilocybin use. Participants were primarily college-educated White men residing in the United States with a prior history of psychedelic use; mean age = 40 years. Participants primarily used dried psilocybin mushrooms (mean dose = 3.1 grams) for "self-exploration" purposes. Prospective longitudinal data collected before and after a planned psilocybin experience on average showed persisting reductions in anxiety, depression, and alcohol misuse, increased cognitive flexibility, emotion regulation, spiritual wellbeing, and extraversion, and reduced neuroticism and burnout after psilocybin use. However, a minority of participants (11% at 2-4 weeks and 7% at 2-3 months) reported persisting negative effects after psilocybin use (e.g., mood fluctuations, depressive symptoms). Discussion Results from this study, the largest prospective survey of naturalistic psilocybin use to date, support the potential for psilocybin to produce lasting improvements in mental health symptoms and general wellbeing.
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Affiliation(s)
- Sandeep M. Nayak
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Hillary Jackson
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Nathan D. Sepeda
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Center for Psychedelic Drug Research and Education, The Ohio State University, Columbus, OH, United States
| | - David S. Mathai
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Sara So
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Abigail Yaffe
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Hadi Zaki
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | | | | | | | - Frederick S. Barrett
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, United States
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Roland R. Griffiths
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Justin C. Strickland
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Matthew W. Johnson
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | | | - Albert Garcia-Romeu
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States
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22
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Wall MB, Harding R, Zafar R, Rabiner EA, Nutt DJ, Erritzoe D. Neuroimaging in psychedelic drug development: past, present, and future. Mol Psychiatry 2023; 28:3573-3580. [PMID: 37759038 PMCID: PMC10730398 DOI: 10.1038/s41380-023-02271-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 09/13/2023] [Indexed: 09/29/2023]
Abstract
Psychedelic therapy (PT) is an emerging paradigm with great transdiagnostic potential for treating psychiatric disorders, including depression, addiction, post-traumatic stress disorder, and potentially others. 'Classic' serotonergic psychedelics, such as psilocybin and lysergic acid diethylamide (LSD), which have a key locus of action at the 5-HT2A receptor, form the main focus of this movement, but substances including ketamine, 3,4-Methylenedioxymethamphetamine (MDMA) and ibogaine also hold promise. The modern phase of development of these treatment modalities in the early 21st century has occurred concurrently with the wider use of advanced human neuroscientific research methods; principally neuroimaging. This can potentially enable assessment of drug and therapy brain effects with greater precision and quantification than any previous novel development in psychiatric pharmacology. We outline the major trends in existing data and suggest the modern development of PT has benefitted greatly from the use of neuroimaging. Important gaps in existing knowledge are identified, namely: the relationship between acute drug effects and longer-term (clinically-relevant) effects, the precise characterisation of effects at the 5-HT2A receptor and relationships with functional/clinical effects, and the possible impact of these compounds on neuroplasticity. A road-map for future research is laid out, outlining clinical studies which will directly address these three questions, principally using combined Positron Emission Tomography (PET) and Magnetic Resonance Imaging (MRI) methods, plus other adjunct techniques. Multimodal (PET/MRI) studies using modern PET techniques such as the 5-HT2A-selective ligand [11 C]Cimbi-36 (and other ligands sensitive to neuroplasticity changes) alongside MRI measures of brain function would provide a 'molecular-functional-clinical bridge' in understanding. Such results would help to resolve some of these questions and provide a firmer foundation for the ongoing development of PT.
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Affiliation(s)
- Matthew B Wall
- Invicro, London, UK.
- Faculty of Medicine, Imperial College London, London, UK.
- Centre for Psychedelic research and Neuropsychopharmacology, Imperial College London, London, UK.
| | - Rebecca Harding
- Clinical Psychopharmacology Unit, Faculty of Brain Sciences, University College London, London, UK
| | - Rayyan Zafar
- Faculty of Medicine, Imperial College London, London, UK
- Centre for Psychedelic research and Neuropsychopharmacology, Imperial College London, London, UK
| | | | - David J Nutt
- Faculty of Medicine, Imperial College London, London, UK
- Centre for Psychedelic research and Neuropsychopharmacology, Imperial College London, London, UK
| | - David Erritzoe
- Faculty of Medicine, Imperial College London, London, UK
- Centre for Psychedelic research and Neuropsychopharmacology, Imperial College London, London, UK
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23
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Delli Pizzi S, Chiacchiaretta P, Sestieri C, Ferretti A, Onofrj M, Della Penna S, Roseman L, Timmermann C, Nutt DJ, Carhart-Harris RL, Sensi SL. Spatial Correspondence of LSD-Induced Variations on Brain Functioning at Rest With Serotonin Receptor Expression. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2023; 8:768-776. [PMID: 37003409 DOI: 10.1016/j.bpsc.2023.03.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 03/14/2023] [Accepted: 03/17/2023] [Indexed: 04/03/2023]
Abstract
BACKGROUND Lysergic acid diethylamide (LSD) is an atypical psychedelic compound that exerts its effects through pleiotropic actions, mainly involving 1A/2A serotoninergic (5-HT) receptor subtypes. However, the mechanisms by which LSD promotes a reorganization of the brain's functional activity and connectivity are still partially unknown. METHODS Our study analyzed resting-state functional magnetic resonance imaging data acquired from 15 healthy volunteers undergoing LSD single-dose intake. A voxelwise analysis investigated the alterations of the brain's intrinsic functional connectivity and local signal amplitude induced by LSD or by a placebo. Quantitative comparisons assessed the spatial overlap between these 2 indices of functional reorganization and the topography of receptor expression obtained from a publicly available collection of in vivo, whole-brain atlases. Finally, linear regression models explored the relationships between changes in resting-state functional magnetic resonance imaging and behavioral aspects of the psychedelic experience. RESULTS LSD elicited modifications of the cortical functional architecture that spatially overlapped with the distribution of serotoninergic receptors. Local signal amplitude and functional connectivity increased in regions belonging to the default mode and attention networks associated with high expression of 5-HT2A receptors. These functional changes correlate with the occurrence of simple and complex visual hallucinations. At the same time, a decrease in local signal amplitude and intrinsic connectivity was observed in limbic areas, which are dense with 5-HT1A receptors. CONCLUSIONS This study provides new insights into the neural processes underlying the brain network reconfiguration induced by LSD. It also identifies a topographical relationship between opposite effects on brain functioning and the spatial distribution of different 5-HT receptors.
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Affiliation(s)
- Stefano Delli Pizzi
- Department of Neuroscience, Imaging, and Clinical Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy; Molecular Neurology Unit, Center for Advanced Studies and Technology, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Piero Chiacchiaretta
- Department of Innovative Technologies in Medicine and Dentistry, "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy; Center for Advanced Studies and Technology, University "G d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Carlo Sestieri
- Department of Neuroscience, Imaging, and Clinical Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy; Institute for Advanced Biomedical Technologies, "G. d'Annunzio" University, Chieti-Pescara, Chieti, Italy
| | - Antonio Ferretti
- Department of Neuroscience, Imaging, and Clinical Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy; Institute for Advanced Biomedical Technologies, "G. d'Annunzio" University, Chieti-Pescara, Chieti, Italy
| | - Marco Onofrj
- Department of Neuroscience, Imaging, and Clinical Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Stefania Della Penna
- Department of Neuroscience, Imaging, and Clinical Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy; Institute for Advanced Biomedical Technologies, "G. d'Annunzio" University, Chieti-Pescara, Chieti, Italy
| | - Leor Roseman
- Centre for Psychedelic Research, Department of Medicine, Imperial College London, London, United Kingdom
| | - Christopher Timmermann
- Centre for Psychedelic Research, Department of Medicine, Imperial College London, London, United Kingdom
| | - David J Nutt
- Centre for Psychedelic Research, Department of Medicine, Imperial College London, London, United Kingdom
| | - Robin L Carhart-Harris
- Centre for Psychedelic Research, Department of Medicine, Imperial College London, London, United Kingdom; Psychedelics Division-Neuroscape, Neurology, University of California San Francisco, San Francisco, California
| | - Stefano L Sensi
- Department of Neuroscience, Imaging, and Clinical Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy; Center for Advanced Studies and Technology, University "G d'Annunzio" of Chieti-Pescara, Chieti, Italy; Institute for Advanced Biomedical Technologies, "G. d'Annunzio" University, Chieti-Pescara, Chieti, Italy.
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24
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Modlin NL, Miller TM, Rucker JJ, Kirlic N, Lennard-Jones M, Schlosser D, Aaronson ST. Optimizing outcomes in psilocybin therapy: Considerations in participant evaluation and preparation. J Affect Disord 2023; 326:18-25. [PMID: 36707036 DOI: 10.1016/j.jad.2023.01.077] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 01/11/2023] [Accepted: 01/21/2023] [Indexed: 01/26/2023]
Abstract
Recent studies have demonstrated the promise of psilocybin therapies in creating positive changes for those with poor mental health across multiple diagnostic categories, including major depressive disorder (MDD), end-of-life anxiety, and obsessive-compulsive disorder (OCD). While there may be a large population that is eligible to participate in psilocybin therapy based on psychiatric diagnosis and medical clearance, little attention has been given to intrapersonal and interpersonal factors that might influence patient's readiness (i.e., eligibility and capacity) for psychedelic interventions. This paper proposes that readiness assessment includes both intrapersonal and interpersonal factors in order to improve safety, patient care, and treatment outcomes. While at the present time a reliable and valid instrument has not been developed, we propose that three specific areas of focus - patient presentation, therapeutic alliance, and patient safety - may be used to establish a patient's readiness for psilocybin therapy, thus increasing therapy optimization and personalization.
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Affiliation(s)
- Nadav Liam Modlin
- The Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Tammy M Miller
- Institute for Advanced Therapeutics and Diagnostics, Sheppard Pratt, Towson, MD, United States of America
| | - James J Rucker
- Department of Psychological Medicine, King's College London, Institute of Psychiatry, Psychology, and Neuroscience, London, United Kingdom; South London and Maudsley National Health Service Foundation Trust, Bethlem Royal Hospital, Beckenham, United Kingdom
| | | | | | - Danielle Schlosser
- Compass Pathfinder Ltd, London, United Kingdom; Weill Institute for Neurosciences, University of California, San Francisco, United States of America
| | - Scott T Aaronson
- Institute for Advanced Therapeutics and Diagnostics, Sheppard Pratt, Towson, MD, United States of America; University of Maryland School of Medicine, Department of Psychiatry, 701 West Pratt Street, Baltimore, MD 21201, United States of America.
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25
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Tulver K, Kaup KK, Laukkonen R, Aru J. Restructuring insight: An integrative review of insight in problem-solving, meditation, psychotherapy, delusions and psychedelics. Conscious Cogn 2023; 110:103494. [PMID: 36913839 DOI: 10.1016/j.concog.2023.103494] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 02/03/2023] [Accepted: 02/26/2023] [Indexed: 03/13/2023]
Abstract
Occasionally, a solution or idea arrives as a sudden understanding - an insight. Insight has been considered an "extra" ingredient of creative thinking and problem-solving. Here we propose that insight is central in seemingly distinct areas of research. Drawing on literature from a variety of fields, we show that besides being commonly studied in problem-solving literature, insight is also a core component in psychotherapy and meditation, a key process underlying the emergence of delusions in schizophrenia, and a factor in the therapeutic effects of psychedelics. In each case, we discuss the event of insight and its prerequisites and consequences. We review evidence for the commonalities and differences between the fields and discuss their relevance for capturing the essence of the insight phenomenon. The goal of this integrative review is to bridge the gap between the different views and inspire interdisciplinary research efforts for understanding this central process of human cognition.
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Affiliation(s)
- Kadi Tulver
- Institute of Computer Science, University of Tartu, Estonia.
| | | | | | - Jaan Aru
- Institute of Computer Science, University of Tartu, Estonia.
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26
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Wießner I, Falchi M, Palhano-Fontes F, Feilding A, Ribeiro S, Tófoli LF. LSD, madness and healing: Mystical experiences as possible link between psychosis model and therapy model. Psychol Med 2023; 53:1151-1165. [PMID: 34253268 DOI: 10.1017/s0033291721002531] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND For a century, psychedelics have been investigated as models of psychosis for demonstrating phenomenological similarities with psychotic experiences and as therapeutic models for treating depression, anxiety, and substance use disorders. This study sought to explore this paradoxical relationship connecting key parameters of the psychotic experience, psychotherapy, and psychedelic experience. METHODS In a randomized, double-blind, placebo-controlled, crossover design, 24 healthy volunteers received 50 μg d-lysergic acid diethylamide (LSD) or inactive placebo. Psychotic experience was assessed by aberrant salience (Aberrant Salience Inventory, ASI), therapeutic potential by suggestibility (Creative Imagination Scale, CIS) and mindfulness (Five Facet Mindfulness Questionnaire, FFMQ; Mindful Attention Awareness Scale, MAAS; Experiences Questionnaire, EQ), and psychedelic experience by four questionnaires (Altered State of Consciousness Questionnaire, ASC; Mystical Experiences Questionnaire, MEQ; Challenging Experiences Questionnaire, CEQ; Ego-Dissolution Inventory, EDI). Relationships between LSD-induced effects were examined. RESULTS LSD induced psychedelic experiences, including alteration of consciousness, mystical experiences, ego-dissolution, and mildly challenging experiences, increased aberrant salience and suggestibility, but not mindfulness. LSD-induced aberrant salience correlated highly with complex imagery, mystical experiences, and ego-dissolution. LSD-induced suggestibility correlated with no other effects. Individual mindfulness changes correlated with aspects of aberrant salience and psychedelic experience. CONCLUSIONS The LSD state resembles a psychotic experience and offers a tool for healing. The link between psychosis model and therapeutic model seems to lie in mystical experiences. The results point to the importance of meaning attribution for the LSD psychosis model and indicate that psychedelic-assisted therapy might benefit from therapeutic suggestions fostering mystical experiences.
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Affiliation(s)
- Isabel Wießner
- Department of Medical Psychology and Psychiatry, School of Medical Sciences, University of Campinas, Campinas, São Paulo, Brazil
- Interdisciplinary Cooperation for Ayahuasca Research and Outreach (ICARO), School of Medical Sciences, University of Campinas, Campinas, São Paulo, Brazil
| | - Marcelo Falchi
- Department of Medical Psychology and Psychiatry, School of Medical Sciences, University of Campinas, Campinas, São Paulo, Brazil
- Interdisciplinary Cooperation for Ayahuasca Research and Outreach (ICARO), School of Medical Sciences, University of Campinas, Campinas, São Paulo, Brazil
| | - Fernanda Palhano-Fontes
- Brain Institute, Federal University of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil
| | | | - Sidarta Ribeiro
- Brain Institute, Federal University of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil
| | - Luís Fernando Tófoli
- Department of Medical Psychology and Psychiatry, School of Medical Sciences, University of Campinas, Campinas, São Paulo, Brazil
- Interdisciplinary Cooperation for Ayahuasca Research and Outreach (ICARO), School of Medical Sciences, University of Campinas, Campinas, São Paulo, Brazil
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27
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Apud I. Ayahuasca and personality. A systematic review and meta-analysis of cross-sectional studies with long-term participants ( Ayahuasca y personalidad. Revisión sistemática y metaanálisis de estudios transversales con participantes de larga trayectoria). STUDIES IN PSYCHOLOGY 2023. [DOI: 10.1080/02109395.2022.2163776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
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28
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Calder AE, Hasler G. Towards an understanding of psychedelic-induced neuroplasticity. Neuropsychopharmacology 2023; 48:104-112. [PMID: 36123427 PMCID: PMC9700802 DOI: 10.1038/s41386-022-01389-z] [Citation(s) in RCA: 44] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 07/10/2022] [Accepted: 07/12/2022] [Indexed: 12/20/2022]
Abstract
Classic psychedelics, such as LSD, psilocybin, and the DMT-containing beverage ayahuasca, show some potential to treat depression, anxiety, and addiction. Importantly, clinical improvements can last for months or years after treatment. It has been theorized that these long-term improvements arise because psychedelics rapidly and lastingly stimulate neuroplasticity. The focus of this review is on answering specific questions about the effects of psychedelics on neuroplasticity. Firstly, we review the evidence that psychedelics promote neuroplasticity and examine the cellular and molecular mechanisms behind the effects of different psychedelics on different aspects of neuroplasticity, including dendritogenesis, synaptogenesis, neurogenesis, and expression of plasticity-related genes (e.g., brain-derived neurotrophic factor and immediate early genes). We then examine where in the brain psychedelics promote neuroplasticity, particularly discussing the prefrontal cortex and hippocampus. We also examine what doses are required to produce this effect (e.g., hallucinogenic doses vs. "microdoses"), and how long purported changes in neuroplasticity last. Finally, we discuss the likely consequences of psychedelics' effects on neuroplasticity for both patients and healthy people, and we identify important research questions that would further scientific understanding of psychedelics' effects on neuroplasticity and its potential clinical applications.
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Affiliation(s)
- Abigail E. Calder
- grid.8534.a0000 0004 0478 1713University Center for Psychiatric Research, University of Fribourg, Fribourg, Switzerland
| | - Gregor Hasler
- University Center for Psychiatric Research, University of Fribourg, Fribourg, Switzerland.
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29
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Urban MM, Stingl MR, Meinhardt MW. Mini-review: The neurobiology of treating substance use disorders with classical psychedelics. Front Neurosci 2023; 17:1156319. [PMID: 37139521 PMCID: PMC10149865 DOI: 10.3389/fnins.2023.1156319] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 03/23/2023] [Indexed: 05/05/2023] Open
Abstract
The potential of psychedelics to persistently treat substance use disorders is known since the 1960s. However, the biological mechanisms responsible for their therapeutic effects have not yet been fully elucidated. While it is known that serotonergic hallucinogens induce changes in gene expression and neuroplasticity, particularly in prefrontal regions, theories on how specifically this counteracts the alterations that occur in neuronal circuitry throughout the course of addiction are largely unknown. This narrative mini-review endeavors to synthesize well-established knowledge from addiction research with findings and theories regarding the neurobiological effects of psychedelics to give an overview of the potential mechanisms that underlie the treatment of substance use disorders with classical hallucinogenic compounds and point out gaps in the current understanding.
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Affiliation(s)
- Marvin M. Urban
- Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, United States
- *Correspondence: Marvin M. Urban,
| | - Moritz R. Stingl
- Interdisciplinary Center for Neurosciences, University of Heidelberg, Heidelberg, Germany
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, United States
| | - Marcus W. Meinhardt
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
- Department of Molecular Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
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30
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Sustained effects of single doses of classical psychedelics in humans. Neuropsychopharmacology 2023; 48:145-150. [PMID: 35729252 PMCID: PMC9700827 DOI: 10.1038/s41386-022-01361-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/19/2022] [Accepted: 06/01/2022] [Indexed: 02/08/2023]
Abstract
The serotonergic classical psychedelics include compounds that primarily activate the brain's serotonin 2 A receptor (5-HT2AR), such as LSD, psilocybin, and DMT (ayahuasca). The acute effects of these compounds are well-known as are their ability to increase the emotional state both in healthy people and in those with neuropsychiatric disorders. In particular psilocybin, the psychoactive constituent in "magic mushrooms", has shown great potential for treatment of anxiety and depression. A unique and compelling feature of psychedelics is that intake of just a single psychedelic dose is associated with long-lasting effects. This includes effects on personality, e.g., higher openness, and amelioration of depressive symptoms. This review focuses on these stunning effects and summarizes our current knowledge on which behavioral, biochemical, neuroimaging, and electrophysiological data support that the intriguing effects of psychedelics on the human brain and mind are based on neural plasticity. The review also points to so far understudied areas and suggests research questions to be addressed in future studies which potentially can help to understand the intriguing long-term effects after intake of a single (or a few) psychedelic doses.
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31
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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
- * E-mail:
| | - 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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Burmester DR, Madsen MK, Szabo A, Aripaka SS, Stenbæk DS, Frokjaer VG, Elfving B, Mikkelsen JD, Knudsen GM, Fisher PM. Subacute effects of a single dose of psilocybin on biomarkers of inflammation in healthy humans: An open-label preliminary investigation. COMPREHENSIVE PSYCHONEUROENDOCRINOLOGY 2022; 13:100163. [PMID: 36545240 PMCID: PMC9761602 DOI: 10.1016/j.cpnec.2022.100163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 12/04/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022] Open
Abstract
Rationale Psilocybin is a serotonergic psychedelic that has gained prominent attention recently as a potential therapeutic for neuropsychiatric disorders including Major Depressive Disorder. Pre-clinical and initial studies in humans suggest that serotonin 2A receptor agonists, including serotonergic psychedelics, have anti-inflammatory effects. This may contribute to its therapeutic effects as previous studies indicate a link between neuropsychiatric disorders and inflammatory processes. However, the effect of psilocybin on biomarkers of inflammation has not been evaluated in humans. Objectives Investigate the effect of a single dose of psilocybin on peripheral biomarkers of inflammation in healthy humans. Methods Blood samples were collected from 16 healthy participants before and one day after the administration of a single oral dose of psilocybin (mean dose: 0.22 mg/kg) and subsequently analyzed for concentrations of high-sensitivity C-reactive protein (hsCRP), tumor-necrosis-factor (TNF) and soluble urokinase plasminogen activator receptor (suPAR). Change in inflammatory markers was evaluated using a paired t-test where p < 0.05 was considered statistically significant. Results We did not observe statistically significant changes in any of the above biomarkers of inflammation (all Cohen's d ≤ 0.31; all p ≥ 0.23). Conclusions Our data do not support that a single dose of psilocybin reduces biomarkers of inflammation in healthy individuals one day after administration. Nevertheless, we suggest that future studies consider additional markers of inflammation, including markers of neuroinflammation, and evaluate potential anti-inflammatory effects of psilocybin therapy in clinical cohorts where more prominent effects may be observable.
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Affiliation(s)
- Daniel Rødbro Burmester
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Martin Korsbak Madsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Faculty of Health and Medicine Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Attila Szabo
- NORMENT Center of Excellence (CoE), Institute of Clinical Medicine, University of Oslo, Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway
| | - Sagar Sanjay Aripaka
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Faculty of Health and Medicine Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Dea Siggaard Stenbæk
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Vibe G. Frokjaer
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Faculty of Health and Medicine Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Psychiatry Copenhagen, Mental Health Services Capital Region, Copenhagen, Denmark
| | - Betina Elfving
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Jens D. Mikkelsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Institute of Neuroscience, University of Copenhagen, Copenhagen, Denmark
| | - Gitte Moos Knudsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Faculty of Health and Medicine Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Patrick MacDonald Fisher
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Corresponding author. Neurobiology Research Unit, Inge Lehmanns Vej 8, Rigshospitalet, Building 8057, DK-2100, Copenhagen, Denmark.
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Olsen AS, Lykkebo-Valløe A, Ozenne B, Madsen MK, Stenbæk DS, Armand S, Mørup M, Ganz M, Knudsen GM, Fisher PM. Psilocybin modulation of time-varying functional connectivity is associated with plasma psilocin and subjective effects. Neuroimage 2022; 264:119716. [PMID: 36341951 DOI: 10.1016/j.neuroimage.2022.119716] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 10/11/2022] [Accepted: 10/25/2022] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Psilocin, the neuroactive metabolite of psilocybin, is a serotonergic psychedelic that induces an acute altered state of consciousness, evokes lasting changes in mood and personality in healthy individuals, and has potential as an antidepressant treatment. Examining the acute effects of psilocin on resting-state time-varying functional connectivity implicates network-level connectivity motifs that may underlie acute and lasting behavioral and clinical effects. AIM Evaluate the association between resting-state time-varying functional connectivity (tvFC) characteristics and plasma psilocin level (PPL) and subjective drug intensity (SDI) before and right after intake of a psychedelic dose of psilocybin in healthy humans. METHODS Fifteen healthy individuals completed the study. Before and at multiple time points after psilocybin intake, we acquired 10-minute resting-state blood-oxygen-level-dependent functional magnetic resonance imaging scans. Leading Eigenvector Dynamics Analysis (LEiDA) and diametrical clustering were applied to estimate discrete, sequentially active brain states. We evaluated associations between the fractional occurrence of brain states during a scan session and PPL and SDI using linear mixed-effects models. We examined associations between brain state dwell time and PPL and SDI using frailty Cox proportional hazards survival analysis. RESULTS Fractional occurrences for two brain states characterized by lateral frontoparietal and medial fronto-parietal-cingulate coherence were statistically significantly negatively associated with PPL and SDI. Dwell time for these brain states was negatively associated with SDI and, to a lesser extent, PPL. Conversely, fractional occurrence and dwell time of a fully connected brain state partly associated with motion was positively associated with PPL and SDI. CONCLUSION Our findings suggest that the acute perceptual psychedelic effects induced by psilocybin may stem from drug-level associated decreases in the occurrence and duration of lateral and medial frontoparietal connectivity motifs. We apply and argue for a modified approach to modeling eigenvectors produced by LEiDA that more fully acknowledges their underlying structure. Together these findings contribute to a more comprehensive neurobiological framework underlying acute effects of serotonergic psychedelics.
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Affiliation(s)
- Anders S Olsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Department of Applied Mathematics and Computer Science, DTU Compute, Kgs. Lyngby, Denmark
| | - Anders Lykkebo-Valløe
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Brice Ozenne
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Department of Public Health, Section of Biostatistics, University of Copenhagen, Copenhagen, Denmark
| | - Martin K Madsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Dea S Stenbæk
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Department of Psychology, University of Copenhagen, Copenhagen, Denmark
| | - Sophia Armand
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Morten Mørup
- Department of Applied Mathematics and Computer Science, DTU Compute, Kgs. Lyngby, Denmark
| | - Melanie Ganz
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Department of Computer Science, University of Copenhagen, Copenhagen, Denmark
| | - Gitte M Knudsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Patrick M Fisher
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
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The Altered States Database: Psychometric data from a systematic literature review. Sci Data 2022; 9:720. [PMID: 36418335 PMCID: PMC9684144 DOI: 10.1038/s41597-022-01822-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 11/01/2022] [Indexed: 11/26/2022] Open
Abstract
In this paper, we present the development of the Altered States Database (ASDB), an open-science project based on a systematic literature review. The ASDB contains psychometric questionnaire data on subjective experiences of altered states of consciousness (ASC) induced by pharmacological and non-pharmacological methods. The systematic review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Scientific journal articles were identified through PubMed and Web of Science. We included studies that examined ASC using the following validated questionnaires: Altered States of Consciousness Rating Scale (APZ, 5D-ASC, 11-ASC), Phenomenology of Consciousness Inventory (PCI), Hallucinogen Rating Scale (HRS), or Mystical Experience Questionnaire (MEQ30). The systematic review resulted in the inclusion of a total of 165 journal articles, whereof questionnaire data was extracted and is now available on the Open Science Framework (OSF) website (https://osf.io/8mbru) and on the ASDB website (http://alteredstatesdb.org), where questionnaire data can be easily retrieved and visualized. This data allows the calculation of comparable psychometric values of ASC experiences and of dose-response relationships of substances inducing ASC. Measurement(s) | Psychometric questionnaire data | Technology Type(s) | Systematic literature review (PRISMA) | Sample Characteristic - Organism | Human |
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Jensen ME, Stenbæk DS, Juul TS, Fisher PM, Ekstrøm CT, Knudsen GM, Fink-Jensen A. Psilocybin-assisted therapy for reducing alcohol intake in patients with alcohol use disorder: protocol for a randomised, double-blinded, placebo-controlled 12-week clinical trial (The QUANTUM Trip Trial). BMJ Open 2022; 12:e066019. [PMID: 36241352 PMCID: PMC9577917 DOI: 10.1136/bmjopen-2022-066019] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 09/30/2022] [Indexed: 02/05/2023] Open
Abstract
INTRODUCTION Alcohol use disorder is a difficult-to-treat psychiatric disorder and a major burden on public health. Existing treatment efficacy is moderate, and relapse rates are high. Preliminary findings suggest that psilocybin, a psychedelic compound, can safely and reliably occasion highly meaningful experiences that may spur a positive change in drinking behaviour when administered in a therapeutic context. However, the efficacy of a single psilocybin administration and its potential neurobiological underpinnings still remain unknown. METHODS AND ANALYSIS To establish efficacy, we will investigate the effects of psilocybin-assisted therapy versus placebo in a randomised, double-blinded, placebo-controlled 12-week clinical trial. Ninety treatment-seeking patients, aged 20-70 years, diagnosed with alcohol use disorder will be recruited from the community via advertisement and referrals from general practitioners or specialised treatment units. The psilocybin or placebo will be administered in accordance with a protocol for psychological support before, during and after the dosing. Outcome assessments will be carried out 1, 4, 8 and 12 weeks postdosing. The primary outcome is reduction in the percentage of heavy drinking days from baseline to follow-up at 12 weeks. Key secondary outcomes are as follows: (1) total alcohol consumption, (2) phosphatidyl-ethanol, an objective biomarker for alcohol, (3) plasma psilocin, the active metabolite, to establish a possible therapeutic range, (4) the acute subjective drug experience as a possible predictor of treatment outcome and (5) neuronal response to alcohol cues and cognitive flexibility within corticostriatal pathways by use of functional MR brain imaging 1-week postdosing. ETHICS AND DISSEMINATION Ethical approval has been obtained from the Committee on Health Research Ethics of the Capital Region of Denmark (H-20043832). All patients will be provided oral and written information about the trial before screening. The study results will be disseminated by peer-review publications and conference presentations. TRIAL REGISTRATION NUMBER EudraCT 2020-000829-55 and NCT05416229.
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Affiliation(s)
| | - Dea Siggaard Stenbæk
- Department of Neurology and Neurobiology Research Unit, Copenhagen University Hospital, Copenhagen, Denmark
- Department of Psychology, University of Copenhagen, Copenhagen, Denmark
| | - Tobias Søgaard Juul
- Psychiatry Centre Copenhagen, Copenhagen University Hospital, Copenhagen, Denmark
| | - Patrick MacDonald Fisher
- Department of Neurology and Neurobiology Research Unit, Copenhagen University Hospital, Copenhagen, Denmark
| | - Claus Thorn Ekstrøm
- Department of Public Health, Section of Biostatistics, University of Copenhagen, Copenhagen, Denmark
| | - Gitte Moos Knudsen
- Department of Neurology and Neurobiology Research Unit, Copenhagen University Hospital, Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Anders Fink-Jensen
- Psychiatry Centre Copenhagen, Copenhagen University Hospital, Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
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36
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Søndergaard A, Madsen MK, Ozenne B, Armand S, Knudsen GM, Fisher PM, Stenbæk DS. Lasting increases in trait mindfulness after psilocybin correlate positively with the mystical-type experience in healthy individuals. Front Psychol 2022; 13:948729. [PMID: 36275302 PMCID: PMC9580465 DOI: 10.3389/fpsyg.2022.948729] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 09/16/2022] [Indexed: 11/13/2022] Open
Abstract
Background Psilocybin-induced mystical-type experiences are associated with lasting positive psychological outcomes. Recent studies indicate that trait mindfulness is increased 3 months after psilocybin intake, preceded by decreases in neocortical serotonin 2A receptor (5-HT2AR) binding. However, the association between psilocybin-induced mystical-type experiences and subsequent changes in trait mindfulness remains unexplored, as does the association between pre-drug trait mindfulness and 5-HT2AR binding in the healthy brain. Aim We evaluated whether psilocybin induced lasting increases in trait mindfulness in healthy volunteers, and whether the mystical-type experience was associated with this increase. We further examined the association between pre-drug trait mindfulness and 5-HT2AR binding in neocortex and selected frontolimbic regions. Materials and methods Forty-six medium-high dose psilocybin sessions were conducted in 39 healthy individuals. The mystical-type experience was measured with the Mystical Experience Questionnaire (MEQ) at the end of the session. Trait mindfulness was measured using the Mindful Attention and Awareness Scale (MAAS) at baseline and 3 months after the psilocybin session. Thirty-two of the participants completed pre-drug [11C]-Cimbi-36 positron emission tomography (PET) to assess 5-HT2AR binding in neocortex and, post-hoc, in the frontolimbic regions amygdala, frontal cortex, and anterior cingulate cortex. Results The MAAS score was significantly increased at 3-month follow-up (p = 3.24 × 10–6), a change positively associated with the MEQ score (p = 0.035). Although the association between pre-drug MAAS score and neocortex 5-HT2AR binding was not significant (p = 0.24), post-hoc analyses revealed a significant negative association between MAAS and right amygdala 5-HT2AR binding (pFWER = 0.008). Conclusion We here show that lasting changes in trait mindfulness following psilocybin administration are positively associated with intensity of the mystical-type experience, suggesting that the acute phenomenology of psilocybin facilitates a shift in awareness conducive for mindful living. We furthermore show that higher pre-drug trait mindfulness is associated with reduced 5-HT2AR binding in the right amygdala.
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Affiliation(s)
- Anna Søndergaard
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Martin Korsbak Madsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Department of Psychiatry, University Hospital Svendborg, Svendborg, Denmark
| | - Brice Ozenne
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Sophia Armand
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Institute of Psychology, University of Copenhagen, Copenhagen, Denmark
| | - Gitte Moos Knudsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Patrick MacDonald Fisher
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Dea Siggaard Stenbæk
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Institute of Psychology, University of Copenhagen, Copenhagen, Denmark
- *Correspondence: Dea Siggaard Stenbæk,
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Dourron HM, Strauss C, Hendricks PS. Self-Entropic Broadening Theory: Toward a New Understanding of Self and Behavior Change Informed by Psychedelics and Psychosis. Pharmacol Rev 2022; 74:982-1027. [DOI: 10.1124/pharmrev.121.000514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 06/14/2022] [Accepted: 06/16/2022] [Indexed: 11/22/2022] Open
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38
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Radakovic C, Radakovic R, Peryer G, Geere JA. Psychedelics and mindfulness: A systematic review and meta-analysis. JOURNAL OF PSYCHEDELIC STUDIES 2022. [DOI: 10.1556/2054.2022.00218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
Background and aims
The benefits of classic serotonergic psychedelics (e.g. psilocybin, LSD, DMT, ayahuasca) are becoming more widely known with the resurgence in research in the past decade. Furthermore, the benefits of mindfulness are well documented. However, no systematic reviews have examined linkage of mindfulness and psychedelics use. The aim of this systematic review is to explore the link between psychedelics and characteristics of mindfulness.
Methods
We conducted a systematic search across multiple databases, inclusive of grey literature and backwards/forward-citation tracking, on the 18 January 2021. The search strategy included terms relating to mindfulness and psychedelics, with no restriction on clinical or non-clinical conditions. Study quality was assessed. An exploratory random-effects meta-analysis was conducted on pre-post mindfulness data relative to psychedelic ingestion.
Results
Of 1805 studies screened, 13 were included in the systematic review. There was substantial variability in participant characteristics, psychedelic administration method and measurement of mindfulness. The ingestion of psychedelics is associated with an increase in mindfulness, specifically relating to domains of acceptance, which encompasses non-judgement of inner experience and non-reactivity. The meta-analysis of a subset of studies (N = 6) showed small effects overall relative to ayahuasca ingestion, increasing mindfulness facets of non-judgement of inner experience and non-reactivity, as well as acting with awareness.
Conclusions
Further methodologically robust research is needed to elucidate the relationship between psychedelics and mindfulness. However, mindfulness and specific facets relating to acceptance have been shown to increase following ingestion of psychedelics in a number of studies.
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Affiliation(s)
- Chelsea Radakovic
- Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom
| | - Ratko Radakovic
- Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom
- Alzheimer Scotland Dementia Research Centre, University of Edinburgh, Edinburgh, United Kingdom
- Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Guy Peryer
- Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom
| | - Jo-Anne Geere
- Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom
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Wei D, Tsheringla S, McPartland JC, Allsop AZASA. Combinatorial approaches for treating neuropsychiatric social impairment. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210051. [PMID: 35858103 PMCID: PMC9274330 DOI: 10.1098/rstb.2021.0051] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 05/13/2022] [Indexed: 01/30/2023] Open
Abstract
Social behaviour is an essential component of human life and deficits in social function are seen across multiple psychiatric conditions with high morbidity. However, there are currently no FDA-approved treatments for social dysfunction. Since social cognition and behaviour rely on multiple signalling processes acting in concert across various neural networks, treatments aimed at social function may inherently require a combinatorial approach. Here, we describe the social neurobiology of the oxytocin and endocannabinoid signalling systems as well as translational evidence for their use in treating symptoms in the social domain. We leverage this systems neurobiology to propose a network-based framework that involves pharmacology, psychotherapy, non-invasive brain stimulation and social skills training to combinatorially target trans-diagnostic social impairment. Lastly, we discuss the combined use of oxytocin and endocannabinoids within our proposed framework as an illustrative strategy to treat specific aspects of social function. Using this framework provides a roadmap for actionable treatment strategies for neuropsychiatric social impairment. This article is part of the theme issue 'Interplays between oxytocin and other neuromodulators in shaping complex social behaviours'.
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Affiliation(s)
- Don Wei
- Department of Psychiatry, UCLA, Los Angeles, CA, USA
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McCulloch DEW, Knudsen GM, Barrett FS, Doss MK, Carhart-Harris RL, Rosas FE, Deco G, Kringelbach ML, Preller KH, Ramaekers JG, Mason NL, Müller F, Fisher PM. Psychedelic resting-state neuroimaging: A review and perspective on balancing replication and novel analyses. Neurosci Biobehav Rev 2022; 138:104689. [PMID: 35588933 DOI: 10.1016/j.neubiorev.2022.104689] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 05/05/2022] [Accepted: 05/05/2022] [Indexed: 12/20/2022]
Abstract
Clinical research into serotonergic psychedelics is expanding rapidly, showing promising efficacy across myriad disorders. Resting-state functional magnetic resonance imaging (rs-fMRI) is a commonly used strategy to identify psychedelic-induced changes in neural pathways in clinical and healthy populations. Here we, a large group of psychedelic imaging researchers, review the 42 research articles published to date, based on the 17 unique studies evaluating psychedelic effects on rs-fMRI, focusing on methodological variation. Prominently, we observe that nearly all studies vary in data processing and analysis methodology, two datasets are the foundation of over half of the published literature, and there is lexical ambiguity in common outcome metric terminology. We offer guidelines for future studies that encourage coherence in the field. Psychedelic rs-fMRI will benefit from the development of novel methods that expand our understanding of the brain mechanisms mediating its intriguing effects; yet, this field is at a crossroads where we must also consider the critical importance of consistency and replicability to effectively converge on stable representations of the neural effects of psychedelics.
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Affiliation(s)
| | - Gitte Moos Knudsen
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark; Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Frederick Streeter Barrett
- Department of Psychiatry and Behavioral Sciences, Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neuroscience and Department of Psychological and Brain Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Manoj K Doss
- Department of Psychiatry and Behavioral Sciences, Center for Psychedelic and Consciousness Research, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robin Lester Carhart-Harris
- Neuroscape, Weill Institute for Neurosciences, University of California San Francisco, CA, USA; Centre for Psychedelic Research, Department of Brain Sciences, Imperial College London, London, UK
| | - Fernando E Rosas
- Centre for Psychedelic Research, Department of Brain Sciences, Imperial College London, London, UK; Data Science Institute, Imperial College London, London, UK; Centre for Complexity Science, Imperial College London, London, UK
| | - Gustavo Deco
- Center for Brain and Cognition, Computational Neuroscience Group, Universitat Pompeu Fabra, Barcelona, Spain; Department of Information and Communication Technologies, Universitat Pompeu Fabra, Barcelona, Spain; Institució Catalana de la Recerca i Estudis Avançats (ICREA), Barcelona, Spain; Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; School of Psychological Sciences, Monash University, Melbourne, Australia
| | - Morten L Kringelbach
- Centre for Eudaimonia and Human Flourishing, Linacre College, University of Oxford, UK; Department of Psychiatry, University of Oxford, Oxford, UK; Center for Music in the Brain, Department of Clinical Medicine, Aarhus University, Denmark
| | - Katrin H Preller
- Pharmaco-Neuroimaging and Cognitive-Emotional Processing, Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric University Hospital, University of Zurich, Zurich, Switzerland
| | | | - Natasha L Mason
- Faculty of Psychology and Neuroscience, Maastricht University, The Netherlands
| | - Felix Müller
- University of Basel, Department of Psychiatry (UPK), Basel, Switzerland
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Vorobyeva N, Kozlova AA. Three Naturally-Occurring Psychedelics and Their Significance in the Treatment of Mental Health Disorders. Front Pharmacol 2022; 13:927984. [PMID: 35837277 PMCID: PMC9274002 DOI: 10.3389/fphar.2022.927984] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 06/06/2022] [Indexed: 12/20/2022] Open
Abstract
Classical psychedelics represent a family of psychoactive substances with structural similarities to serotonin and affinity for serotonin receptors. A growing number of studies have found that psychedelics can be effective in treating various psychiatric conditions, including post-traumatic stress disorder, major depressive disorder, anxiety, and substance use disorders. Mental health disorders are extremely prevalent in the general population constituting a major problem for the public health. There are a wide variety of interventions for mental health disorders, including pharmacological therapies and psychotherapies, however, treatment resistance still remains a particular challenge in this field, and relapse rates are also quite high. In recent years, psychedelics have become one of the promising new tools for the treatment of mental health disorders. In this review, we will discuss the three classic serotonergic naturally occurring psychedelics, psilocybin, ibogaine, and N, N-dimethyltryptamine, focusing on their pharmacological properties and clinical potential. The purpose of this article is to provide a focused review of the most relevant research into the therapeutic potential of these substances and their possible integration as alternative or adjuvant options to existing pharmacological and psychological therapies.
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Affiliation(s)
- Nataliya Vorobyeva
- Hive Bio Life Sciences Ltd., London, United Kingdom
- *Correspondence: Nataliya Vorobyeva,
| | - Alena A. Kozlova
- Department of Psychiatry and Psychotherapy, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
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42
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Johnson S, Letheby C. Psychedelic therapy for body dysmorphic disorder. JOURNAL OF PSYCHEDELIC STUDIES 2022. [DOI: 10.1556/2054.2022.00200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
In this opinion piece we propose the investigation of psychedelic-assisted psychotherapy for the treatment of body dysmorphic disorder (BDD). BDD is a psychiatric disorder characterised by appearance-based preoccupations and accompanying compulsions. While safe and effective treatments for BDD exist, non-response and relapse rates remain high. Therefore, there is a need to investigate promising new treatment options for this highly debilitating condition. Preliminary evidence suggests safety, feasibility, and potential efficacy of psychedelic treatments in disorders that share similar psychopathological mechanisms with BDD. Drawing on this evidence, as well as on relevant qualitative reports and theoretical proposals, we argue that it would be worthwhile to conduct a phase 2a study aimed at assessing the safety and feasibility of psychedelic-assisted psychotherapy in BDD. We also offer some suggestions for how future research ought to proceed.
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Affiliation(s)
- Shevaugn Johnson
- College of Education, Psychology, and Social Work, Flinders University, Sturt Road, Bedford Park, South Australia, 5042, Australia
| | - Chris Letheby
- Department of Philosophy, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia, 6009, Australia
- Department of Philosophy, The University of Adelaide, North Terrace, Adelaide, South Australia, 5005, Australia
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43
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Hartong V, van Emmerik A. Psychedelic Microdosing, Mindfulness, and Anxiety: A Cross-Sectional Mediation Study. J Psychoactive Drugs 2022:1-11. [PMID: 35694791 DOI: 10.1080/02791072.2022.2080616] [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: 10/18/2022]
Abstract
While anecdotal reports claim that psychedelic microdosing reduces anxiety and mood symptoms, evidence supporting these claims is scarce. This cross-sectional study investigated the association between microdosing and trait anxiety. Furthermore, it was investigated if trait mindfulness mediated this association. Participants completed anonymous online questionnaires and were divided into three groups: current microdosers (n = 186), former microdosers (n = 77) and microdosing-naïve controls (n = 234). Trait anxiety and trait mindfulness were measured using the State-Trait Anxiety Inventory - Trait subscale (STAI-T) and the 15-item Five-Facet Mindfulness Questionnaire (FFMQ-15) respectively. Current and former microdosers reported lower STAI-T scores compared to microdosing-naïve controls. Furthermore, associations of current and former microdosing with trait anxiety were mediated by trait mindfulness, with small effects of FFMQ-15 Total, Non-judging and Non-reactivity scores. However, in an exploratory analysis, all associations between microdosing and STAI-T scores became non-significant when participants with previous macrodose experience (n = 386) were excluded. Our findings suggest that RCT<apos;>s are warranted to test causal hypotheses concerning the effects of microdosing and the role of trait mindfulness in the effects of microdosing, while controlling for previous macrodose experience.
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Affiliation(s)
- Vincent Hartong
- Department of Psychology, Faculty of Social and Behavioural Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Arnold van Emmerik
- Department of Psychology, Faculty of Social and Behavioural Sciences, University of Amsterdam, Amsterdam, Netherlands
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44
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McCulloch DEW, Grzywacz MZ, Madsen MK, Jensen PS, Ozenne B, Armand S, Knudsen GM, Fisher PM, Stenbæk DS. Psilocybin-Induced Mystical-Type Experiences are Related to Persisting Positive Effects: A Quantitative and Qualitative Report. Front Pharmacol 2022; 13:841648. [PMID: 35355714 PMCID: PMC8959755 DOI: 10.3389/fphar.2022.841648] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 02/08/2022] [Indexed: 11/16/2022] Open
Abstract
Psychedelic drugs such as psilocybin have shown substantial promise for the treatment of several psychiatric conditions including mood and addictive disorders. They also have the remarkable property of producing persisting positive psychological changes in healthy volunteers for at least several months. In this study (NCT03289949), 35 medium-high doses of psilocybin were administered to 28 healthy volunteers (12 females). By the end of the dosing day, participants reported the intensity of their acute experience using the 30-item Mystical Experience Questionnaire (MEQ) and an open-form qualitative report from home. Persisting psychological effects attributed to the psilocybin experience were measured using the Persisting Effects Questionnaire (PEQ) 3-months after administration. Using a linear latent-variable model we show that the MEQ total score is positively associated with the later emergence of positive PEQ effects (p = 3 × 10−5). Moreover, the MEQ subscales “Positive Mood” (pcorr = 4.1 × 10−4) and “Mysticality” (pcorr = 2.0 × 10−4) are associated with positive PEQ whereas the subscales “Transcendence of Time and Space” (pcorr = 0.38) and “Ineffability” (pcorr = 0.45) are not. Using natural language pre-processing, we provide the first qualitative descriptions of the “Complete Mystical Experience” induced by orally administered psilocybin in healthy volunteers, revealing themes such as a sense of connection with the Universe, familial love, and the experience of profound beauty. Combining qualitative and quantitative methods, this paper expands understanding of the acute psilocybin induced experience in healthy volunteers and suggests an importance of the type of experience in predicting lasting positive effects.
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Affiliation(s)
- Drummond E-Wen McCulloch
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Maria Zofia Grzywacz
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Martin Korsbak Madsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Peter Steen Jensen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Brice Ozenne
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.,Department of Public Health, Section of Biostatistics, University of Copenhagen, Copenhagen, Denmark
| | - Sophia Armand
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Gitte Moos Knudsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.,Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Patrick MacDonald Fisher
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Dea Siggaard Stenbæk
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.,Department of Psychology, University of Copenhagen, Copenhagen, Denmark
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45
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Hasler G. Toward the "helioscope" hypothesis of psychedelic therapy. Eur Neuropsychopharmacol 2022; 57:118-119. [PMID: 35227963 DOI: 10.1016/j.euroneuro.2022.02.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/03/2022] [Accepted: 02/07/2022] [Indexed: 11/16/2022]
Affiliation(s)
- Gregor Hasler
- Unit of Psychiatry Research, University of Fribourg, Chemin du Cardinal-Journet 3, 1752 Villars-sur-Glâne, Fribourg, Switzerland
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46
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Deo N, Redpath G. Serotonin Receptor and Transporter Endocytosis Is an Important Factor in the Cellular Basis of Depression and Anxiety. Front Cell Neurosci 2022; 15:804592. [PMID: 35280519 PMCID: PMC8912961 DOI: 10.3389/fncel.2021.804592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 12/16/2021] [Indexed: 11/13/2022] Open
Abstract
Depression and anxiety are common, debilitating psychiatric conditions affecting millions of people throughout the world. Current treatments revolve around selective serotonin reuptake inhibitors (SSRIs), yet these drugs are only moderately effective at relieving depression. Moreover, up to 30% of sufferers are SSRI non-responders. Endocytosis, the process by which plasma membrane and extracellular constituents are internalized into the cell, plays a central role in the regulation of serotonin (5-hydroxytryptophan, 5-HT) signaling, SSRI function and depression and anxiety pathogenesis. Despite their therapeutic potential, surprisingly little is known about the endocytosis of the serotonin receptors (5-HT receptors) or the serotonin transporter (SERT). A subset of 5-HT receptors are endocytosed by clathrin-mediated endocytosis following serotonin binding, while for the majority of 5-HT receptors the endocytic regulation is not known. SERT internalizes serotonin from the extracellular space into the cell to limit the availability of serotonin for receptor binding and signaling. Endocytosis of SERT reduces serotonin uptake, facilitating serotonin signaling. SSRIs predominantly inhibit SERT, preventing serotonin uptake to enhance 5-HT receptor signaling, while hallucinogenic compounds directly activate specific 5-HT receptors, altering their interaction with endocytic adaptor proteins to induce alternate signaling outcomes. Further, multiple polymorphisms and transcriptional/proteomic alterations have been linked to depression, anxiety, and SSRI non-response. In this review, we detail the endocytic regulation of 5-HT receptors and SERT and outline how SSRIs and hallucinogenic compounds modulate serotonin signaling through endocytosis. Finally, we will examine the deregulated proteomes in depression and anxiety and link these with 5-HT receptor and SERT endocytosis. Ultimately, in attempting to integrate the current studies on the cellular biology of depression and anxiety, we propose that endocytosis is an important factor in the cellular basis of depression and anxiety. We will highlight how a thorough understanding 5-HT receptor and SERT endocytosis is integral to understanding the biological basis of depression and anxiety, and to facilitate the development of a next generation of specific, efficacious antidepressant treatments.
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Affiliation(s)
- Nikita Deo
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
| | - Gregory Redpath
- European Molecular Biology Lab (EMBL) Australia Node in Single Molecule Science, School of Medical Sciences and the Australian Research Council (ARC) Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, NSW, Australia
- *Correspondence: Gregory Redpath
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47
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Psilocybin for Treating Psychiatric Disorders: A Psychonaut Legend or a Promising Therapeutic Perspective? J Xenobiot 2022; 12:41-52. [PMID: 35225956 PMCID: PMC8883979 DOI: 10.3390/jox12010004] [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: 06/25/2021] [Revised: 10/26/2021] [Accepted: 11/24/2021] [Indexed: 11/30/2022] Open
Abstract
Psychedelics extracted from plants have been used in religious, spiritual, and mystic practices for millennia. In 1957, Dr. Hofmann identified and synthesized the prodrug psilocybin, a substance present in more than 200 species of psychedelic mushrooms. Although there were limitations related to the scientific design of many studies, clinical observations performed during the 1950s and 1960s showed a potential therapeutic effect of psilocybin for patients affected by depressive symptoms, anxiety, and conversion disorder. Psilocybin was classed as a schedule I substance in 1970, but the fascination with psychedelics has remained almost unchanged over time, promoting a new scientific interest starting in the 1990s. Recent studies have provided further evidence supporting the suggestive hypothesis of the therapeutic use of psilocybin for treating various psychiatric disorders, including pathological anxiety, mood depressive disorder, and addiction.
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48
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Rieser NM, Herdener M, Preller KH. Psychedelic-Assisted Therapy for Substance Use Disorders and Potential Mechanisms of Action. Curr Top Behav Neurosci 2022; 56:187-211. [PMID: 34910289 DOI: 10.1007/7854_2021_284] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Substance use disorders (SUD) represent a significant public health issue with a high need for novel and efficacious treatment options. In light of this high unmet need, recent results reporting beneficial outcomes of psychedelic-assisted therapy in SUD are particularly relevant. However, several questions remain with regard to this treatment approach. The clinical mechanisms of action of psychedelic substances in the treatment of SUD are not well understood. Closing this knowledge gap is critical to inform and optimize the psychotherapeutic embedding of the acute substance administration. In this chapter, we discuss potential mechanisms that have implications on psychotherapeutic approaches including induced neuroplasticity, alterations in brain network connectivity, reward and emotion processing, social connectedness, insight, and mystical experiences. Furthermore, we outline considerations and approaches that leverage these mechanisms in order to optimize the therapeutic embedding by maximizing synergy between substance effects and psychotherapy. Understanding the mechanisms of action, developing psychotherapeutic approaches accordingly, and evaluating their synergistic efficacy in scientific studies will be critical to advance the framework of psychedelic-assisted therapy for addiction, create evidence-based approaches, and achieve the best treatment outcome for patients with SUD.
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Affiliation(s)
- Nathalie M Rieser
- Pharmaco-Neuroimaging and Cognitive-Emotional Processing, Department of Psychiatry, Psychotherapy and Psychosomatics, University of Zurich, Psychiatric University Hospital Zurich, Zurich, Switzerland.
| | - Marcus Herdener
- Center for Addictive Disorders, Department of Psychiatry, Psychotherapy and Psychosomatics, University of Zurich, Psychiatric University Hospital Zurich, Zurich, Switzerland
| | - Katrin H Preller
- Pharmaco-Neuroimaging and Cognitive-Emotional Processing, Department of Psychiatry, Psychotherapy and Psychosomatics, University of Zurich, Psychiatric University Hospital Zurich, Zurich, Switzerland
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49
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McCulloch DEW, Madsen MK, Stenbæk DS, Kristiansen S, Ozenne B, Jensen PS, Knudsen GM, Fisher PM. Lasting effects of a single psilocybin dose on resting-state functional connectivity in healthy individuals. J Psychopharmacol 2022; 36:74-84. [PMID: 34189985 PMCID: PMC8801642 DOI: 10.1177/02698811211026454] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
BACKGROUND Psilocybin is a psychedelic drug that has shown lasting positive effects on clinical symptoms and self-reported well-being following a single dose. There has been little research into the long-term effects of psilocybin on brain connectivity in humans. AIM Evaluate changes in resting-state functional connectivity (RSFC) at 1 week and 3 months after one psilocybin dose in 10 healthy psychedelic-naïve volunteers and explore associations between change in RSFC and related measures. METHODS Participants received 0.2-0.3 mg/kg psilocybin in a controlled setting. Participants completed resting-state functional magnetic resonance imaging (fMRI) scans at baseline, 1-week and 3-month post-administration and [11C]Cimbi-36 PET scans at baseline and 1 week. We examined changes in within-network, between-network and region-to-region RSFC. We explored associations between changes in RSFC and psilocybin-induced phenomenology as well as changes in psychological measures and neocortex serotonin 2A receptor binding. RESULTS Psilocybin was well tolerated and produced positive changes in well-being. At 1 week only, executive control network (ECN) RSFC was significantly decreased (Cohen's d = -1.73, pFWE = 0.010). We observed no other significant changes in RSFC at 1 week or 3 months, nor changes in region-to-region RSFC. Exploratory analyses indicated that decreased ECN RSFC at 1 week predicted increased mindfulness at 3 months (r = -0.65). CONCLUSIONS These findings in a small cohort indicate that psilocybin affects ECN function within the psychedelic 'afterglow' period. Our findings implicate ECN modulation as mediating psilocybin-induced, long-lasting increases in mindfulness. Although our findings implicate a neural pathway mediating lasting psilocybin effects, it is notable that changes in neuroimaging measures at 3 months, when personality changes are observed, remain to be identified.
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Affiliation(s)
| | - Martin Korsbak Madsen
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark,Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Dea Siggaard Stenbæk
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark,Department of Psychology, University of Copenhagen, Copenhagen, Denmark
| | - Sara Kristiansen
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark
| | - Brice Ozenne
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark,Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Peter Steen Jensen
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark
| | - Gitte Moos Knudsen
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark,Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Patrick MacDonald Fisher
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark,Patrick MacDonald Fisher, Neurobiology Research Unit, Rigshospitalet Building 8057, 8 Inge Lehmanns Vej, Copenhagen 2100, Denmark.
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50
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Kiraga MK, Kuypers KPC, Uthaug MV, Ramaekers JG, Mason NL. Decreases in State and Trait Anxiety Post-psilocybin: A Naturalistic, Observational Study Among Retreat Attendees. Front Psychiatry 2022; 13:883869. [PMID: 35873251 PMCID: PMC9300865 DOI: 10.3389/fpsyt.2022.883869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 06/01/2022] [Indexed: 12/02/2022] Open
Abstract
Anxiety disorders are the most common type of psychiatric disorders among Western countries. Evidence-based treatment modalities including pharmacological and cognitive-behavioral therapy result in deficient treatment responses. Historical and recent research suggests psychedelic drugs may be efficacious in alleviating anxiety-related symptoms among healthy and clinical populations. The main aim of the present study was investigation of the effects of psilocybin-containing truffles, when taken in a supportive group setting, on ratings of state and trait anxiety across self-reported healthy volunteers. Attendees of psilocybin ceremonies were asked to complete a test battery at three separate occasions: before the ceremony (baseline), the morning after, and 1 week after the ceremony. The test battery included questionnaires assessing state and trait anxiety (State-Trait Anxiety Inventory), mindfulness capacities (Five Facet Mindfulness Questionnaire), and personality (Big Five Inventory). Additionally, the psychedelic experience was quantified with the Persisting Effects Questionnaire and the Ego Dissolution Inventory. The total amount of psilocybin-containing truffles consumed by each participant was recorded, and a sample of the truffles was analyzed to determine psilocin concentrations. Fifty-two attendees (males = 25; females = 25; others = 2) completed parts of the baseline assessment, 46 (males = 21; females = 24; others = 1) completed assessments the morning after the ceremony, and 23 (males = 10; females = 13) completed assessments at the 1-week follow-up. Average psilocin consumption across individuals was 27.1 mg. The morning after the ceremony, we observed medium reductions in anxiety measures (both state and trait) compared to baseline ( d ¯ = 6.4; p < 0.001 and d ¯ = 6; p = 0.014, respectively), which persisted over a 1-week period post-ceremony ( d ¯ = 6.7; p = 0.001 and d ¯ = 8.6; p = 0.004, respectively). At 1 week post-ceremony, the non-judging facet of the mindfulness scale was increased ( d ¯ = 1.5; p = 0.03), while the personality trait neuroticism decreased ( d ¯ = 5.2; p = 0.005), when compared to baseline. Additionally, we found ratings of ego dissolution (mean: 59.7, SD: 28.3) and changes in neuroticism to be the strongest predictors of reductions in state and trait anxiety, respectively. In sum, results suggest rapid and persisting (up to 1 week) anxiolytic effects in individuals with sub-clinical anxiety symptoms, which are related to the acute experience of ego dissolution, as well as lasting changes in trait neuroticism. Results also add support to the feasibility and potential efficacy of group sessions with psychedelics. To understand whether these effects extend to wider populations suffering from heightened anxiety, and the mechanisms involved, further experimental research is needed.
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Affiliation(s)
- Maggie Kamila Kiraga
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Kim P C Kuypers
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Malin Vedoy Uthaug
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Johannes G Ramaekers
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Natasha Leigh Mason
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
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