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Caspani G, Ruffell SGD, Tsang W, Netzband N, Rohani-Shukla C, Swann JR, Jefferies WA. Mind over matter: the microbial mindscapes of psychedelics and the gut-brain axis. Pharmacol Res 2024; 207:107338. [PMID: 39111558 DOI: 10.1016/j.phrs.2024.107338] [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: 07/16/2024] [Revised: 07/31/2024] [Accepted: 07/31/2024] [Indexed: 08/12/2024]
Abstract
Psychedelics have emerged as promising therapeutics for several psychiatric disorders. Hypotheses around their mechanisms have revolved around their partial agonism at the serotonin 2 A receptor, leading to enhanced neuroplasticity and brain connectivity changes that underlie positive mindset shifts. However, these accounts fail to recognise that the gut microbiota, acting via the gut-brain axis, may also have a role in mediating the positive effects of psychedelics on behaviour. In this review, we present existing evidence that the composition of the gut microbiota may be responsive to psychedelic drugs, and in turn, that the effect of psychedelics could be modulated by microbial metabolism. We discuss various alternative mechanistic models and emphasize the importance of incorporating hypotheses that address the contributions of the microbiome in future research. Awareness of the microbial contribution to psychedelic action has the potential to significantly shape clinical practice, for example, by allowing personalised psychedelic therapies based on the heterogeneity of the gut microbiota.
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Affiliation(s)
- Giorgia Caspani
- Michael Smith Laboratories, University of British Columbia, 2185 East Mall, East Mall, BC V6T 1Z4, Canada; Department of Microbiology and Immunology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z4, Canada; Centre for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z4, Canada; The Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2215 Wesbrook Mall, Vancouver, BC V6T 1Z4, Canada; The Vancouver Prostate Centre, Vancouver General Hospital, 2660 Oak Street, Vancouver, BC V6H 3Z6, Canada; Department of Medical Genetics, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z4, Canada; Department of Urologic Sciences, University of British Columbia, Gordon & Leslie Diamond Health Care Centre, Level 6, 2775 Laurel Street, Vancouver, BC V5Z 1M9, Canada.
| | - Simon G D Ruffell
- Psychae Institute, Melbourne, Australia; School of Population and Global Health, University of Melbourne, 207 Bouverie St, Carlton, VIC 3053, Australia
| | - WaiFung Tsang
- Institute of Psychiatry, Psychology & Neuroscience, King'sCollege London, Department of Psychology, De Crespigny Park, London SE5 8AF, UK
| | - Nigel Netzband
- University of West of England, Frenchay Campus, Coldharbour Lane, Bristol BS16 1QY, UK
| | - Cyrus Rohani-Shukla
- Centre for Psychedelic Research, Imperial College London, Hammersmith Hospital, Du Cane Rd, London W12 0HS, UK
| | - Jonathan R Swann
- School of Human Development and Health, Faculty of Medicine, University of Southampton, 12 University Rd, Southampton SO17 1BJ, UK; Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Wilfred A Jefferies
- Michael Smith Laboratories, University of British Columbia, 2185 East Mall, East Mall, BC V6T 1Z4, Canada; Department of Microbiology and Immunology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z4, Canada; Centre for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z4, Canada; The Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2215 Wesbrook Mall, Vancouver, BC V6T 1Z4, Canada; The Vancouver Prostate Centre, Vancouver General Hospital, 2660 Oak Street, Vancouver, BC V6H 3Z6, Canada; Department of Medical Genetics, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z4, Canada; Department of Urologic Sciences, University of British Columbia, Gordon & Leslie Diamond Health Care Centre, Level 6, 2775 Laurel Street, Vancouver, BC V5Z 1M9, Canada.
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Colwell MJ, Tagomori H, Shang F, Cheng HI, Wigg CE, Browning M, Cowen PJ, Murphy SE, Harmer CJ. Direct serotonin release in humans shapes aversive learning and inhibition. Nat Commun 2024; 15:6617. [PMID: 39122687 PMCID: PMC11315928 DOI: 10.1038/s41467-024-50394-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: 09/30/2023] [Accepted: 07/09/2024] [Indexed: 08/12/2024] Open
Abstract
The role of serotonin in human behaviour is informed by approaches which allow in vivo modification of synaptic serotonin. However, characterising the effects of increased serotonin signalling in human models of behaviour is challenging given the limitations of available experimental probes, notably selective serotonin reuptake inhibitors. Here we use a now-accessible approach to directly increase synaptic serotonin in humans (a selective serotonin releasing agent) and examine its influence on domains of behaviour historically considered core functions of serotonin. Computational techniques, including reinforcement learning and drift diffusion modelling, explain participant behaviour at baseline and after week-long intervention. Reinforcement learning models reveal that increasing synaptic serotonin reduces sensitivity for outcomes in aversive contexts. Furthermore, increasing synaptic serotonin enhances behavioural inhibition, and shifts bias towards impulse control during exposure to aversive emotional probes. These effects are seen in the context of overall improvements in memory for neutral verbal information. Our findings highlight the direct effects of increasing synaptic serotonin on human behaviour, underlining its role in guiding decision-making within aversive and more neutral contexts, and offering implications for longstanding theories of central serotonin function.
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Affiliation(s)
- Michael J Colwell
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK.
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK.
| | - Hosana Tagomori
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Fei Shang
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Hoi Iao Cheng
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Chloe E Wigg
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Michael Browning
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Philip J Cowen
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Susannah E Murphy
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Catherine J Harmer
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK.
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK.
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Siegel JS, Subramanian S, Perry D, Kay BP, Gordon EM, Laumann TO, Reneau TR, Metcalf NV, Chacko RV, Gratton C, Horan C, Krimmel SR, Shimony JS, Schweiger JA, Wong DF, Bender DA, Scheidter KM, Whiting FI, Padawer-Curry JA, Shinohara RT, Chen Y, Moser J, Yacoub E, Nelson SM, Vizioli L, Fair DA, Lenze EJ, Carhart-Harris R, Raison CL, Raichle ME, Snyder AZ, Nicol GE, Dosenbach NUF. Psilocybin desynchronizes the human brain. Nature 2024; 632:131-138. [PMID: 39020167 PMCID: PMC11291293 DOI: 10.1038/s41586-024-07624-5] [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: 10/24/2023] [Accepted: 05/29/2024] [Indexed: 07/19/2024]
Abstract
A single dose of psilocybin, a psychedelic that acutely causes distortions of space-time perception and ego dissolution, produces rapid and persistent therapeutic effects in human clinical trials1-4. In animal models, psilocybin induces neuroplasticity in cortex and hippocampus5-8. It remains unclear how human brain network changes relate to subjective and lasting effects of psychedelics. Here we tracked individual-specific brain changes with longitudinal precision functional mapping (roughly 18 magnetic resonance imaging visits per participant). Healthy adults were tracked before, during and for 3 weeks after high-dose psilocybin (25 mg) and methylphenidate (40 mg), and brought back for an additional psilocybin dose 6-12 months later. Psilocybin massively disrupted functional connectivity (FC) in cortex and subcortex, acutely causing more than threefold greater change than methylphenidate. These FC changes were driven by brain desynchronization across spatial scales (areal, global), which dissolved network distinctions by reducing correlations within and anticorrelations between networks. Psilocybin-driven FC changes were strongest in the default mode network, which is connected to the anterior hippocampus and is thought to create our sense of space, time and self. Individual differences in FC changes were strongly linked to the subjective psychedelic experience. Performing a perceptual task reduced psilocybin-driven FC changes. Psilocybin caused persistent decrease in FC between the anterior hippocampus and default mode network, lasting for weeks. Persistent reduction of hippocampal-default mode network connectivity may represent a neuroanatomical and mechanistic correlate of the proplasticity and therapeutic effects of psychedelics.
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Affiliation(s)
- Joshua S Siegel
- Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA.
| | - Subha Subramanian
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Demetrius Perry
- Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA
| | - Benjamin P Kay
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Evan M Gordon
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Timothy O Laumann
- Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA
| | - T Rick Reneau
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Nicholas V Metcalf
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Ravi V Chacko
- Department of Emergency Medicine, Advocate Christ Health Care, Oak Lawn, IL, USA
| | - Caterina Gratton
- Department of Psychology, Florida State University, Tallahassee, FL, USA
| | | | - Samuel R Krimmel
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Joshua S Shimony
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Julie A Schweiger
- Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA
| | - Dean F Wong
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - David A Bender
- Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA
| | - Kristen M Scheidter
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Forrest I Whiting
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Jonah A Padawer-Curry
- Department of Biomedical Engineering, Washington University in St Louis, St Louis, MO, USA
| | - Russell T Shinohara
- Center for Biomedical Image Computing and Analytics, University of Pennsylvania, Philadelphia, PA, USA
- Penn Statistics in Imaging and Visualization Endeavor, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Biostatistics, Epidemiology and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yong Chen
- Department of Biostatistics, Epidemiology and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Julia Moser
- Masonic Institute for the Developing Brain, University of Minnesota, Minneapolis, MN, USA
- Institute of Child Development, University of Minnesota, Minneapolis, MN, USA
| | - Essa Yacoub
- Center for Magnetic Resonance Research (CMRR), University of Minnesota, Minneapolis, MN, USA
| | - Steven M Nelson
- Masonic Institute for the Developing Brain, University of Minnesota, Minneapolis, MN, USA
- Department of Pediatrics, University of Minnesota, Minneapolis, MN, USA
| | - Luca Vizioli
- Center for Magnetic Resonance Research (CMRR), University of Minnesota, Minneapolis, MN, USA
| | - Damien A Fair
- Masonic Institute for the Developing Brain, University of Minnesota, Minneapolis, MN, USA
- Institute of Child Development, University of Minnesota, Minneapolis, MN, USA
- Center for Magnetic Resonance Research (CMRR), University of Minnesota, Minneapolis, MN, USA
- Department of Pediatrics, University of Minnesota, Minneapolis, MN, USA
| | - Eric J Lenze
- Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA
| | - Robin Carhart-Harris
- Department of Neurology, University of California, San Francisco, CA, USA
- Centre for Psychedelic Research, Imperial College London, London, UK
| | - Charles L Raison
- Usona Institute, Fitchburg, WI, USA
- Department of Psychiatry, University of Wisconsin School of Medicine & Public Health, Madison, WI, USA
| | - Marcus E Raichle
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
- Department of Biomedical Engineering, Washington University in St Louis, St Louis, MO, USA
- Department of Psychological and Brain Sciences, Washington University in St Louis, St Louis, MO, USA
- Department of Neuroscience, Washington University School of Medicine, St Louis, MO, USA
| | - Abraham Z Snyder
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Ginger E Nicol
- Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA
| | - Nico U F Dosenbach
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
- Department of Biomedical Engineering, Washington University in St Louis, St Louis, MO, USA
- Department of Psychological and Brain Sciences, Washington University in St Louis, St Louis, MO, USA
- Department of Pediatrics, Washington University School of Medicine, St Louis, MO, USA
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Yu Z, Burback L, Winkler O, Xu L, Dennett L, Vermetten E, Greenshaw A, Li XM, Milne M, Wang F, Cao B, Winship IR, Zhang Y, Chan AW. Alterations in brain network connectivity and subjective experience induced by psychedelics: a scoping review. Front Psychiatry 2024; 15:1386321. [PMID: 38807690 PMCID: PMC11131165 DOI: 10.3389/fpsyt.2024.1386321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 04/23/2024] [Indexed: 05/30/2024] Open
Abstract
Intense interest surrounds current research on psychedelics, particularly regarding their potential in treating mental health disorders. Various studies suggest a link between the subjective effects produced by psychedelics and their therapeutic efficacy. Neuroimaging evidence indicates an association of changes in brain functional connectivity with the subjective effects of psychedelics. We conducted a review focusing on psychedelics and brain functional connectivity. The review focused on four psychedelic drugs: ayahuasca, psilocybin and LSD, and the entactogen MDMA. We conducted searches in databases of MEDLINE, Embase, APA PsycInfo and Scopus from inception to Jun 2023 by keywords related to functional connectivity and psychedelics. Using the PRISMA framework, we selected 24 articles from an initial pool of 492 for analysis. This scoping review and analysis investigated the effects of psychedelics on subjective experiences and brain functional connectivity in healthy individuals. The studies quantified subjective effects through psychometric scales, revealing significant experiences of altered consciousness, mood elevation, and mystical experiences induced by psychedelics. Neuroimaging results indicated alterations in the functional connectivity of psychedelics, with consistent findings across substances of decreased connectivity within the default mode network and increased sensory and thalamocortical connectivity. Correlations between these neurophysiological changes and subjective experiences were noted, suggesting a brain network basis of the psychedelics' neuropsychological impact. While the result of the review provides a potential neural mechanism of the subjective effects of psychedelics, direct clinical evidence is needed to advance their clinical outcomes. Our research serves as a foundation for further exploration of the therapeutic potential of psychedelics.
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Affiliation(s)
- Zijia Yu
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
| | - Lisa Burback
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
| | - Olga Winkler
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
| | - Lujie Xu
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
| | - Liz Dennett
- Sperber Health Sciences Library, University of Alberta, Edmonton, AB, Canada
| | - Eric Vermetten
- Department of Psychiatry, Leiden University Medical Centre, Leiden, Netherlands
| | - Andrew Greenshaw
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Xin-Min Li
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Michaela Milne
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
- Institute of Human Nutrition at the Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, United States
| | - Fei Wang
- Nanjing Medical University Affiliated Brain Hospital, Nanjing, Jiangsu, China
| | - Bo Cao
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Ian R. Winship
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Yanbo Zhang
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Allen W. Chan
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
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Lewis EC, Jaeger A, Girn M, Omene E, Brendle M, Argento E. Exploring psychedelic-assisted therapy in the treatment of functional seizures: A review of underlying mechanisms and associated brain networks. J Psychopharmacol 2024; 38:407-416. [PMID: 38654554 PMCID: PMC11102649 DOI: 10.1177/02698811241248395] [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: 04/26/2024]
Abstract
Functional seizures (FS), the most common subtype of functional neurological disorder (FND), cause serious neurological disability and significantly impact quality of life. Characterized by episodic disturbances of functioning that resemble epileptic seizures, FS coincide with multiple comorbidities and are treated poorly by existing approaches. Novel treatment approaches are sorely needed. Notably, mounting evidence supports the safety and efficacy of psychedelic-assisted therapy (PAT) for several psychiatric conditions, motivating investigations into whether this efficacy also extends to neurological disorders. Here, we synthesize past empirical findings and frameworks to construct a biopsychosocial mechanistic argument for the potential of PAT as a treatment for FS. In doing so, we highlight FS as a well-defined cohort to further understand the large-scale neural mechanisms underpinning PAT. Our synthesis is guided by a complexity science perspective which we contend can afford unique mechanistic insight into both FS and PAT, as well as help bridge these two domains. We also leverage this perspective to propose a novel analytic roadmap to identify markers of FS diagnostic specificity and treatment success. This endeavor continues the effort to bridge clinical neurology with psychedelic medicine and helps pave the way for a new field of psychedelic neurology.
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Affiliation(s)
- Evan Cole Lewis
- Hospital for Sick Children, Department of Pediatrics, University of Toronto, Toronto, ON, Canada
| | | | - Manesh Girn
- Neuroscape, Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | | | - Madeline Brendle
- Numinus Wellness Inc., Vancouver, BC, Canada
- Health Outcomes Division, College of Pharmacy, University of Texas at Austin, Austin, TX, USA
| | - Elena Argento
- Numinus Wellness Inc., Vancouver, BC, Canada
- Department of Psychology, University of British Columbia, Kelowna, BC, Canada
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Siegel JS, Subramanian S, Perry D, Kay B, Gordon E, Laumann T, Reneau R, Gratton C, Horan C, Metcalf N, Chacko R, Schweiger J, Wong D, Bender D, Padawer-Curry J, Raison C, Raichle M, Lenze EJ, Snyder AZ, Dosenbach NUF, Nicol G. Psilocybin desynchronizes brain networks. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.08.22.23294131. [PMID: 37701731 PMCID: PMC10493007 DOI: 10.1101/2023.08.22.23294131] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/14/2023]
Abstract
1The relationship between the acute effects of psychedelics and their persisting neurobiological and psychological effects is poorly understood. Here, we tracked brain changes with longitudinal precision functional mapping in healthy adults before, during, and for up to 3 weeks after oral psilocybin and methylphenidate (17 MRI visits per participant) and again 6+ months later. Psilocybin disrupted connectivity across cortical networks and subcortical structures, producing more than 3-fold greater acute changes in functional networks than methylphenidate. These changes were driven by desynchronization of brain activity across spatial scales (area, network, whole brain). Psilocybin-driven desynchronization was observed across association cortex but strongest in the default mode network (DMN), which is connected to the anterior hippocampus and thought to create our sense of self. Performing a perceptual task reduced psilocybin-induced network changes, suggesting a neurobiological basis for grounding, connecting with physical reality during psychedelic therapy. The acute brain effects of psilocybin are consistent with distortions of space-time and the self. Psilocybin induced persistent decrease in functional connectivity between the anterior hippocampus and cortex (and DMN in particular), lasting for weeks but normalizing after 6 months. Persistent suppression of hippocampal-DMN connectivity represents a candidate neuroanatomical and mechanistic correlate for psilocybin's pro-plasticity and anti-depressant effects.
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7
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A complex systems perspective on psychedelic brain action. Trends Cogn Sci 2023; 27:433-445. [PMID: 36740518 DOI: 10.1016/j.tics.2023.01.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 01/10/2023] [Accepted: 01/17/2023] [Indexed: 02/05/2023]
Abstract
Recent findings suggesting the potential transdiagnostic efficacy of psychedelic-assisted therapy have fostered the need to deepen our understanding of psychedelic brain action. Functional neuroimaging investigations have found that psychedelics reduce the functional segregation of large-scale brain networks. However, beyond this general trend, findings have been largely inconsistent. We argue here that a perspective based on complexity science that foregrounds the distributed, interactional, and dynamic nature of brain function may render these inconsistencies intelligible. We propose that psychedelics induce a mode of brain function that is more dynamically flexible, diverse, integrated, and tuned for information sharing, consistent with greater criticality. This 'meta' perspective has the potential to unify past findings and guide intuitions toward compelling mechanistic models.
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8
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Singleton SP, Wang JB, Mithoefer M, Hanlon C, George MS, Mithoefer A, Mithoefer O, Coker AR, Yazar-Klosinski B, Emerson A, Doblin R, Kuceyeski A. Altered brain activity and functional connectivity after MDMA-assisted therapy for post-traumatic stress disorder. Front Psychiatry 2023; 13:947622. [PMID: 36713926 PMCID: PMC9879604 DOI: 10.3389/fpsyt.2022.947622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 12/19/2022] [Indexed: 01/15/2023] Open
Abstract
Introduction 3,4-methylenedioxymethamphetamine-assisted therapy (MDMA-AT) for post-traumatic stress disorder (PTSD) has demonstrated promise in multiple clinical trials. MDMA is hypothesized to facilitate the therapeutic process, in part, by decreasing fear response during fear memory processing while increasing extinction learning. The acute administration of MDMA in healthy controls modifies recruitment of brain regions involved in the hyperactive fear response in PTSD such as the amygdala, hippocampus, and insula. However, to date there have been no neuroimaging studies aimed at directly elucidating the neural impact of MDMA-AT in PTSD patients. Methods We analyzed brain activity and connectivity via functional MRI during both rest and autobiographical memory (trauma and neutral) response before and two-months after MDMA-AT in nine veterans and first-responders with chronic PTSD of 6 months or more. Results We hypothesized that MDMA-AT would increase amygdala-hippocampus resting-state functional connectivity, however we only found evidence of a trend in the left amygdala-left hippocampus (t = -2.91, uncorrected p = 0.0225, corrected p = 0.0901). We also found reduced activation contrast (trauma > neutral) after MDMA-AT in the cuneus. Finally, the amount of recovery from PTSD after MDMA-AT correlated with changes in four functional connections during autobiographical memory recall: the left amygdala-left posterior cingulate cortex (PCC), left amygdala-right PCC, left amygdala-left insula, and left isthmus cingulate-left posterior hippocampus. Discussion Amygdala-insular functional connectivity is reliably implicated in PTSD and anxiety, and both regions are impacted by MDMA administration. These findings compliment previous research indicating that amygdala, hippocampus, and insula functional connectivity is a potential target of MDMA-AT, and highlights other regions of interest related to memory processes. More research is necessary to determine if these findings are specific to MDMA-AT compared to other types of treatment for PTSD. Clinical trial registration https://clinicaltrials.gov/ct2/show/NCT02102802, identifier NCT02102802.
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Affiliation(s)
- S. Parker Singleton
- Department of Computational Biology, Cornell University, Ithaca, NY, United States
| | - Julie B. Wang
- MAPS Public Benefit Corporation, San Jose, CA, United States
| | - Michael Mithoefer
- MAPS Public Benefit Corporation, San Jose, CA, United States
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States
| | - Colleen Hanlon
- Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Mark S. George
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States
- Ralph H. Johnson VA Medical Center, Charleston, SC, United States
| | - Annie Mithoefer
- MAPS Public Benefit Corporation, San Jose, CA, United States
| | - Oliver Mithoefer
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States
| | - Allison R. Coker
- MAPS Public Benefit Corporation, San Jose, CA, United States
- Department of Neurology, University of California, San Francisco, San Francisco, CA, United States
| | | | - Amy Emerson
- MAPS Public Benefit Corporation, San Jose, CA, United States
| | - Rick Doblin
- Multidisciplinary Association for Psychedelic Studies, San Jose, CA, United States
| | - Amy Kuceyeski
- Department of Computational Biology, Cornell University, Ithaca, NY, United States
- Department of Radiology, Weill Cornell Medicine, New York, NY, United States
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9
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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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10
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Abstract
BACKGROUND Postpartum depression (PPD) is a major public health concern and has, at its core, a sense of maternal 'disconnection' - from the self, the infant, and the support system. While PPD bears similarities with MDD, there is increasing evidence for its distinct nature, especially with the unique aspect of the mother-infant relationship. Current treatment modalities for PPD, largely based on those used in major depressive disorder (MDD), have low remission rates with emerging evidence for treatment resistance. It is, therefore, necessary to explore alternative avenues of treatment for PPD. OBJECTIVE In this narrative review, we outline the potential therapeutic rationale for serotonergic psychedelics in the treatment of PPD, and highlight safety and pragmatic considerations for the use of psychedelics in the postpartum period. METHODS We examined the available evidence for the treatment of PPD and the evidence for psychedelics in the treatment of MDD. We explored safety considerations in the use of psychedelics in the postpartum period. RESULTS There is increasing evidence for safety, and encouraging signals for efficacy, of psilocybin in the treatment of MDD. Psilocybin has been shown to catalyse a sense of 'reconnection' in participants with MDD. This effect in PPD, by fostering a sense of 'reconnection' for the mother, may allow for improved mood and maternal sensitivity towards the infant, which can positively impact maternal role gratification and the mother-infant relationship. CONCLUSION Psychedelic assisted therapy in PPD may have a positive effect on the mother-infant dyad and warrants further examination.
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Affiliation(s)
- Chaitra Jairaj
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK,The National Maternity Hospital, Dublin, Ireland,Chaitra Jairaj, Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, De Crespigny Park, London SE5 8AF, UK.
| | - James J Rucker
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK,Bethlem Royal Hospital, South London and Maudsley National Health Service Foundation Trust, Beckenham, UK
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11
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van Elk M, Yaden DB. Pharmacological, neural, and psychological mechanisms underlying psychedelics: A critical review. Neurosci Biobehav Rev 2022; 140:104793. [PMID: 35878791 DOI: 10.1016/j.neubiorev.2022.104793] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 07/08/2022] [Accepted: 07/20/2022] [Indexed: 10/17/2022]
Abstract
This paper provides a critical review of several possible mechanisms at different levels of analysis underlying the effects and therapeutic potential of psychedelics. At the (1) biochemical level, psychedelics primarily affect the 5-HT2A receptor, increase neuroplasticity, offer a critical period for social reward learning, and have anti-inflammatory properties. At the (2) neural level, psychedelics have been associated with reduced efficacy of thalamo-cortical filtering, the loosening of top-down predictive signaling and an increased sensitivity to bottom-up prediction errors, and activation of the claustro-cortical-circuit. At the (3) psychological level, psychedelics have been shown to induce altered and affective states, they affect cognition, induce belief change, exert social effects, and can result in lasting changes in behavior. We outline the potential for a unifying account of the mechanisms underlying psychedelics and contrast this with a model of pluralistic causation. Ultimately, a better understanding of the specific mechanisms underlying the effects of psychedelics could allow for a more targeted therapeutic approach. We highlight current challenges for psychedelic research and provide a research agenda to foster insight in the causal-mechanistic pathways underlying the efficacy of psychedelic research and therapy.
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Affiliation(s)
- Michiel van Elk
- Institute of Psychology, Leiden University, Wassenaarseweg 52, 2333 AK Leiden, the Netherlands.
| | - David Bryce Yaden
- The Center for Psychedelic and Consciousness Research, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, USA
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12
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Sarparast A, Thomas K, Malcolm B, Stauffer CS. Drug-drug interactions between psychiatric medications and MDMA or psilocybin: a systematic review. Psychopharmacology (Berl) 2022; 239:1945-1976. [PMID: 35253070 PMCID: PMC9177763 DOI: 10.1007/s00213-022-06083-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 02/03/2022] [Indexed: 12/13/2022]
Abstract
RATIONALE & OBJECTIVES ± 3,4-Methylenedioxymethamphetamine (MDMA) and psilocybin are currently moving through the US Food and Drug Administration's phased drug development process for psychiatric treatment indications: posttraumatic stress disorder and depression, respectively. The current standard of care for these disorders involves treatment with psychiatric medications (e.g., selective serotonin reuptake inhibitors), so it will be important to understand drug-drug interactions between MDMA or psilocybin and psychiatric medications. METHODS In accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we queried the MEDLINE database via PubMed for publications of human studies in English spanning between the first synthesis of psilocybin (1958) and December 2020. We used 163 search terms containing 22 psychiatric medication classes, 135 specific psychiatric medications, and 6 terms describing MDMA or psilocybin. RESULTS Forty publications were included in our systematic review: 26 reporting outcomes from randomized controlled studies with healthy adults, 3 epidemiologic studies, and 11 case reports. Publications of studies describe interactions between MDMA (N = 24) or psilocybin (N = 5) and medications from several psychiatric drug classes: adrenergic agents, antipsychotics, anxiolytics, mood stabilizers, NMDA antagonists, psychostimulants, and several classes of antidepressants. We focus our results on pharmacodynamic, physiological, and subjective outcomes of drug-drug interactions. CONCLUSIONS As MDMA and psilocybin continue to move through the FDA drug development process, this systematic review offers a compilation of existing research on psychiatric drug-drug interactions with MDMA or psilocybin.
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Affiliation(s)
- Aryan Sarparast
- Department of Psychiatry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Kelan Thomas
- College of Pharmacy, Touro University California, Vallejo, CA, 94592, USA
| | | | - Christopher S Stauffer
- Department of Psychiatry, Oregon Health & Science University, Portland, OR, 97239, USA.
- Department of Mental Health, VA Portland Health Care System, Portland, OR, 97239, USA.
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13
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Avram M, Müller F, Rogg H, Korda A, Andreou C, Holze F, Vizeli P, Ley L, Liechti ME, Borgwardt S. Characterizing thalamocortical (dys)connectivity following d-amphetamine, LSD, and MDMA administration. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2022; 7:885-894. [PMID: 35500840 DOI: 10.1016/j.bpsc.2022.04.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 03/28/2022] [Accepted: 04/13/2022] [Indexed: 12/19/2022]
Abstract
BACKGROUND Patients with psychotic disorders present alterations in thalamocortical intrinsic functional connectivity (iFC) as measured by resting-state functional magnetic resonance imaging (rs-fMRI). Specifically, thalamic iFC is increased with sensorimotor cortices (hyperconnectivity) and decreased with prefrontal-limbic cortices (hypoconnectivity). Intriguingly, psychedelics such as lysergic acid diethylamide (LSD) elicit similar thalamocortical-hyperconnectivity with sensorimotor areas in healthy volunteers. It is unclear whether LSD also induces thalamocortical-hypoconnectivity with prefrontal-limbic cortices as current findings are equivocal. Notably, thalamocortical-hyperconnectivity was associated with psychotic symptoms in patients and substance-induced altered states of consciousness in healthy volunteers. Thalamocortical dysconnectivity is likely evoked by altered neurotransmission, e.g., via dopaminergic excess in psychotic disorders and serotonergic agonism in psychedelic-induced states. It is unclear whether thalamocortical dysconnectivity is also elicited by amphetamine-type substances, broadly releasing monoamines (i.e., dopamine, norepinephrine) but producing fewer perceptual effects than psychedelics. METHODS We administrated LSD, d-amphetamine, and 3,4-methylenedioxymethamphetamine (MDMA) in 28 healthy volunteers and investigated their effects on thalamic iFC with two brain networks (auditory-sensorimotor (ASM) and salience (SAL) - corresponding to sensorimotor and prefrontal-limbic cortices, respectively), using a double-blind, placebo-controlled, cross-over design. RESULTS All active substances elicited ASM-thalamic-hyperconnectivity compared to placebo, despite predominantly distinct pharmacological actions and subjective effects. LSD-induced effects correlated with subjective changes in perception, indicating a link between hyperconnectivity and psychedelic-type perceptual alterations. Unlike d-amphetamine and MDMA, which induced hypoconnectivity with SAL, LSD elicited hyperconnectivity. D-amphetamine and MDMA evoked similar thalamocortical dysconnectivity patterns. CONCLUSIONS Psychedelics, empathogens, and psychostimulants evoke thalamocortical-hyperconnectivity with sensorimotor areas, akin to findings in patients with psychotic disorders.
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Affiliation(s)
- Mihai Avram
- Translational Psychiatry, Department of Psychiatry and Psychotherapy, University of Lübeck, Lübeck, 23538, Germany.
| | - Felix Müller
- Department of Psychiatry (UPK), University of Basel, Basel, 4012, Switzerland
| | - Helena Rogg
- Translational Psychiatry, Department of Psychiatry and Psychotherapy, University of Lübeck, Lübeck, 23538, Germany
| | - Alexandra Korda
- Translational Psychiatry, Department of Psychiatry and Psychotherapy, University of Lübeck, Lübeck, 23538, Germany
| | - Christina Andreou
- Translational Psychiatry, Department of Psychiatry and Psychotherapy, University of Lübeck, Lübeck, 23538, Germany
| | - Friederike Holze
- Division of Clinical Pharmacology and Toxicology, Department of Clinical Research, University Hospital Basel, University of Basel, Basel, 4031, Switzerland
| | - Patrick Vizeli
- Division of Clinical Pharmacology and Toxicology, Department of Clinical Research, University Hospital Basel, University of Basel, Basel, 4031, Switzerland
| | - Laura Ley
- Division of Clinical Pharmacology and Toxicology, Department of Clinical Research, University Hospital Basel, University of Basel, Basel, 4031, Switzerland
| | - Matthias E Liechti
- Division of Clinical Pharmacology and Toxicology, Department of Clinical Research, University Hospital Basel, University of Basel, Basel, 4031, Switzerland
| | - Stefan Borgwardt
- Translational Psychiatry, Department of Psychiatry and Psychotherapy, University of Lübeck, Lübeck, 23538, Germany
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14
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Thomas CW, Blanco-Duque C, Bréant BJ, Goodwin GM, Sharp T, Bannerman DM, Vyazovskiy VV. Psilocin acutely alters sleep-wake architecture and cortical brain activity in laboratory mice. Transl Psychiatry 2022; 12:77. [PMID: 35197453 PMCID: PMC8866416 DOI: 10.1038/s41398-022-01846-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 02/02/2022] [Accepted: 02/03/2022] [Indexed: 01/03/2023] Open
Abstract
Serotonergic psychedelic drugs, such as psilocin (4-hydroxy-N,N-dimethyltryptamine), profoundly alter the quality of consciousness through mechanisms which are incompletely understood. Growing evidence suggests that a single psychedelic experience can positively impact long-term psychological well-being, with relevance for the treatment of psychiatric disorders, including depression. A prominent factor associated with psychiatric disorders is disturbed sleep, and the sleep-wake cycle is implicated in the homeostatic regulation of neuronal activity and synaptic plasticity. However, it remains largely unknown to what extent psychedelic agents directly affect sleep, in terms of both acute arousal and homeostatic sleep regulation. Here, chronic electrophysiological recordings were obtained in mice to track sleep-wake architecture and cortical activity after psilocin injection. Administration of psilocin led to delayed REM sleep onset and reduced NREM sleep maintenance for up to approximately 3 h after dosing, and the acute EEG response was associated primarily with an enhanced oscillation around 4 Hz. No long-term changes in sleep-wake quantity were found. When combined with sleep deprivation, psilocin did not alter the dynamics of homeostatic sleep rebound during the subsequent recovery period, as reflected in both sleep amount and EEG slow-wave activity. However, psilocin decreased the recovery rate of sleep slow-wave activity following sleep deprivation in the local field potentials of electrodes targeting the medial prefrontal and surrounding cortex. It is concluded that psilocin affects both global vigilance state control and local sleep homeostasis, an effect which may be relevant for its antidepressant efficacy.
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Affiliation(s)
- Christopher W. Thomas
- grid.4991.50000 0004 1936 8948Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Cristina Blanco-Duque
- grid.4991.50000 0004 1936 8948Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Benjamin J. Bréant
- grid.4991.50000 0004 1936 8948Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Guy M. Goodwin
- grid.4991.50000 0004 1936 8948Department of Psychiatry, University of Oxford, Oxford, UK
| | - Trevor Sharp
- grid.4991.50000 0004 1936 8948Department of Pharmacology, University of Oxford, Oxford, UK
| | - David M. Bannerman
- grid.4991.50000 0004 1936 8948Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Vladyslav V. Vyazovskiy
- grid.4991.50000 0004 1936 8948Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
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15
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Vollenweider FX, Smallridge JW. Classic Psychedelic Drugs: Update on Biological
Mechanisms. PHARMACOPSYCHIATRY 2022; 55:121-138. [PMID: 35079988 PMCID: PMC9110100 DOI: 10.1055/a-1721-2914] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Renewed interest in the effects of psychedelics in the treatment of psychiatric
disorders warrants a better understanding of the neurobiological mechanisms
underlying the effects of these substances. During the past two decades,
state-of-the-art studies of animals and humans have yielded new important
insights into the molecular, cellular, and systems-level actions of psychedelic
drugs. These efforts have revealed that psychedelics affect primarily
serotonergic receptor subtypes located in cortico-thalamic and cortico-cortical
feedback circuits of information processing. Psychedelic drugs modulate
excitatory-inhibitory balance in these circuits and can participate in
neuroplasticity within brain structures critical for the integration of
information relevant to sensation, cognition, emotions, and the narrative of
self. Neuroimaging studies showed that characteristic dimensions of the
psychedelic experience obtained through subjective questionnaires as well as
alterations in self-referential processing and emotion regulation obtained
through neuropsychological tasks are associated with distinct changes in brain
activity and connectivity patterns at multiple-system levels. These recent
results suggest that changes in self-experience, emotional processing, and
social cognition may contribute to the potential therapeutic effects of
psychedelics.
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Affiliation(s)
- Franz X. Vollenweider
- Neuropsychopharmacology and Brain Imaging, Department of Psychiatry,
Psychotherapy and Psychosomatics, University Hospital for Psychiatry Zurich,
Zurich, Switzerland
| | - John W. Smallridge
- Neuropsychopharmacology and Brain Imaging, Department of Psychiatry,
Psychotherapy and Psychosomatics, University Hospital for Psychiatry Zurich,
Zurich, Switzerland
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16
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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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17
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Kelly JR, Gillan CM, Prenderville J, Kelly C, Harkin A, Clarke G, O'Keane V. Psychedelic Therapy's Transdiagnostic Effects: A Research Domain Criteria (RDoC) Perspective. Front Psychiatry 2021; 12:800072. [PMID: 34975593 PMCID: PMC8718877 DOI: 10.3389/fpsyt.2021.800072] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 11/19/2021] [Indexed: 12/12/2022] Open
Abstract
Accumulating clinical evidence shows that psychedelic therapy, by synergistically combining psychopharmacology and psychological support, offers a promising transdiagnostic treatment strategy for a range of disorders with restricted and/or maladaptive habitual patterns of emotion, cognition and behavior, notably, depression (MDD), treatment resistant depression (TRD) and addiction disorders, but perhaps also anxiety disorders, obsessive-compulsive disorder (OCD), Post-Traumatic Stress Disorder (PTSD) and eating disorders. Despite the emergent transdiagnostic evidence, the specific clinical dimensions that psychedelics are efficacious for, and associated underlying neurobiological pathways, remain to be well-characterized. To this end, this review focuses on pre-clinical and clinical evidence of the acute and sustained therapeutic potential of psychedelic therapy in the context of a transdiagnostic dimensional systems framework. Focusing on the Research Domain Criteria (RDoC) as a template, we will describe the multimodal mechanisms underlying the transdiagnostic therapeutic effects of psychedelic therapy, traversing molecular, cellular and network levels. These levels will be mapped to the RDoC constructs of negative and positive valence systems, arousal regulation, social processing, cognitive and sensorimotor systems. In summarizing this literature and framing it transdiagnostically, we hope we can assist the field in moving toward a mechanistic understanding of how psychedelics work for patients and eventually toward a precise-personalized psychedelic therapy paradigm.
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Affiliation(s)
- John R. Kelly
- Department of Psychiatry, Trinity College, Dublin, Ireland
- Department of Psychiatry, Tallaght University Hospital, Dublin, Ireland
| | - Claire M. Gillan
- Trinity College Institute of Neuroscience, Trinity College, Dublin, Ireland
- School of Psychology, Trinity College, Dublin, Ireland
- Global Brain Health Institute, Trinity College, Dublin, Ireland
| | - Jack Prenderville
- Transpharmation Ireland Ltd, Institute of Neuroscience, Trinity College, Dublin, Ireland
- Discipline of Physiology, School of Medicine, Trinity College, Dublin, Ireland
| | - Clare Kelly
- Department of Psychiatry, Trinity College, Dublin, Ireland
- Trinity College Institute of Neuroscience, Trinity College, Dublin, Ireland
- School of Psychology, Trinity College, Dublin, Ireland
| | - Andrew Harkin
- Trinity College Institute of Neuroscience, Trinity College, Dublin, Ireland
- School of Pharmacy and Pharmaceutical Sciences, Trinity College, Dublin, Ireland
| | - Gerard Clarke
- Department of Psychiatry and Neurobehavioral Science, University College Cork, Cork, Ireland
- APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Veronica O'Keane
- Department of Psychiatry, Trinity College, Dublin, Ireland
- Department of Psychiatry, Tallaght University Hospital, Dublin, Ireland
- Trinity College Institute of Neuroscience, Trinity College, Dublin, Ireland
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18
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Ona G, Sampedro F, Romero S, Valle M, Camacho V, Migliorelli C, Mañanas MÁ, Antonijoan RM, Puntes M, Coimbra J, Ballester MR, Garrido M, Riba J. The Kappa Opioid Receptor and the Sleep of Reason: Cortico-Subcortical Imbalance Following Salvinorin-A. Int J Neuropsychopharmacol 2021; 25:54-63. [PMID: 34537829 PMCID: PMC8756086 DOI: 10.1093/ijnp/pyab063] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 08/25/2021] [Accepted: 09/15/2021] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The mechanisms through which kappa opioid receptor (KOR) agonists induce psychotomimetic effects are largely unknown, although the modulation of this receptor has attracted attention for its clinical use. In this work, we characterize the neuropharmacological effects of salvinorin-A, a highly selective KOR agonist. METHODS Changes in multimodal electroencephalography, single-photon emission computed tomography, and subjective effects following the acute administration of salvinorin-A are reported. The study included 2 sub-studies that employed a double-blind, crossover, randomized, placebo-controlled design. RESULTS The electroencephalography measures showed a marked increase in delta and gamma waves and a decrease in alpha waves while subjects were under the effect of salvinorin-A. Regarding single-photon emission computed tomography measures, significant decreases in regional cerebral blood flow were detected in multiple regions of the frontal, temporal, parietal, and occipital cortices. Significant regional cerebral blood flow increases were observed in some regions of the medial temporal lobe, including the amygdala, the hippocampal gyrus, and the cerebellum. The pattern of subjective effects induced by salvinorin-A was similar to those observed in relation to other psychotomimetic drugs but with an evidently dissociative nature. No dysphoric effects were reported. CONCLUSION The salvinorin-A-mediated KOR agonism induced dramatic psychotomimetic effects along with a generalized decrease in cerebral blood flow and electric activity within the cerebral cortex.
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Affiliation(s)
- Genís Ona
- Human Neuropsychopharmacology Group, Sant Pau Institute of Biomedical Research (IIB-Sant Pau), Barcelona, Spain
| | - Frederic Sampedro
- Sant Pau Institute of Biomedical Research (IIB-Sant Pau), Barcelona, Spain,Centro de Investigación en Red-Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain,Correspondence: Frederic Sampedro, PhD, Hospital de Sant Pau Research Institute, Sant Quintí Street number 77, 08041 Barcelona, Spain ()
| | - Sergio Romero
- Department of Automatic Control (ESAII), Biomedical Engineering Research Center (CREB), Universitat Politècnica de Catalunya (UPC), Barcelona, Spain,Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Barcelona, Spain
| | - Marta Valle
- Departament de Farmacologia i Terapèutica, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Valle Camacho
- Nuclear Medicine Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Carolina Migliorelli
- Department of Automatic Control (ESAII), Biomedical Engineering Research Center (CREB), Universitat Politècnica de Catalunya (UPC), Barcelona, Spain,Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Barcelona, Spain
| | - Miguel Ángel Mañanas
- Department of Automatic Control (ESAII), Biomedical Engineering Research Center (CREB), Universitat Politècnica de Catalunya (UPC), Barcelona, Spain,Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Barcelona, Spain
| | - Rosa Maria Antonijoan
- Departament de Farmacologia i Terapèutica, Universitat Autònoma de Barcelona, Barcelona, Spain,Centre d’Investigació de Medicaments, Sant Pau Institute of Biomedical Research (IIB-Sant Pau), Barcelona, Spain,Servei de Farmacologia Clínica, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain,Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Spain
| | - Montserrat Puntes
- Centre d’Investigació de Medicaments, Sant Pau Institute of Biomedical Research (IIB-Sant Pau), Barcelona, Spain
| | - Jimena Coimbra
- Centre d’Investigació de Medicaments, Sant Pau Institute of Biomedical Research (IIB-Sant Pau), Barcelona, Spain
| | - Maria Rosa Ballester
- Centre d’Investigació de Medicaments, Sant Pau Institute of Biomedical Research (IIB-Sant Pau), Barcelona, Spain,Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Spain,Blanquerna School of Health Science, Universitat Ramon Llull, Barcelona, Spain
| | - Maite Garrido
- Centre d’Investigació de Medicaments, Sant Pau Institute of Biomedical Research (IIB-Sant Pau), Barcelona, Spain
| | - Jordi Riba
- Department of Neuropsychology and Psychopharmacology, Maastricht University, Maastricht,the Netherlands
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19
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Madsen MK, Stenbæk DS, Arvidsson A, Armand S, Marstrand-Joergensen MR, Johansen SS, Linnet K, Ozenne B, Knudsen GM, Fisher PM. Psilocybin-induced changes in brain network integrity and segregation correlate with plasma psilocin level and psychedelic experience. Eur Neuropsychopharmacol 2021; 50:121-132. [PMID: 34246868 DOI: 10.1016/j.euroneuro.2021.06.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 06/04/2021] [Accepted: 06/07/2021] [Indexed: 11/28/2022]
Abstract
The emerging novel therapeutic psilocybin produces psychedelic effects via engagement of cerebral serotonergic targets by psilocin (active metabolite). The serotonin 2A receptor critically mediates these effects by altering distributed neural processes that manifest as increased entropy, reduced functional connectivity (FC) within discrete brain networks (i.e., reduced integrity) and increased FC between networks (i.e., reduced segregation). Reduced integrity of the default mode network (DMN) is proposed to play a particularly prominent role in psychedelic phenomenology, including perceived ego-dissolution. Here, we investigate the effects of a psychoactive peroral dose of psilocybin (0.2-0.3 mg/kg) on plasma psilocin level (PPL), subjective drug intensity (SDI) and their association in fifteen healthy individuals. We further evaluate associations between these measures and resting-state FC, measured with functional magnetic resonance imaging, acquired over the course of five hours after psilocybin administration. We show that PPL and SDI correlate negatively with measures of network integrity (including DMN) and segregation, both spatially constrained and unconstrained. We also find that the executive control network and dorsal attention network desegregate, increasing connectivity with other networks and throughout the brain as a function of PPL and SDI. These findings provide direct evidence that psilocin critically shapes the time course and magnitude of changes in the cerebral functional architecture and subjective experience following psilocybin administration. Our findings provide novel insight into the neurobiological mechanisms underlying profound perceptual experiences evoked by this emerging transnosological therapeutic and implicate the expression of network integrity and segregation in the psychedelic experience and consciousness.
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Affiliation(s)
- Martin K Madsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Dea S Stenbæk
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark
| | - Albin Arvidsson
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark
| | - Sophia Armand
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark
| | - Maja R Marstrand-Joergensen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark
| | - Sys S Johansen
- Section of Forensic Chemistry, Department of Forensic Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Kristian Linnet
- Section of Forensic Chemistry, Department of Forensic Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Brice Ozenne
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Gitte M Knudsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Patrick M Fisher
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark.
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20
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Yaden DB, Johnson MW, Griffiths RR, Doss MK, Garcia-Romeu A, Nayak S, Gukasyan N, Mathur BN, Barrett FS. Psychedelics and Consciousness: Distinctions, Demarcations, and Opportunities. Int J Neuropsychopharmacol 2021; 24:615-623. [PMID: 33987652 PMCID: PMC8378075 DOI: 10.1093/ijnp/pyab026] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/06/2021] [Accepted: 05/10/2021] [Indexed: 12/13/2022] Open
Abstract
Psychedelic substances produce unusual and compelling changes in conscious experience that have prompted some to propose that psychedelics may provide unique insights explaining the nature of consciousness. At present, psychedelics, like other current scientific tools and methods, seem unlikely to provide information relevant to the so-called "hard problem of consciousness," which involves explaining how first-person experience can emerge. However, psychedelics bear on multiple "easy problems of consciousness," which involve relations between subjectivity, brain function, and behavior. In this review, we discuss common meanings of the term "consciousness" when used with regard to psychedelics and consider some models of the effects of psychedelics on the brain that have also been associated with explanatory claims about consciousness. We conclude by calling for epistemic humility regarding the potential for psychedelic research to aid in explaining the hard problem of consciousness while pointing to ways in which psychedelics may advance the study of many specific aspects of consciousness.
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Affiliation(s)
- David B Yaden
- Department of Psychiatry and Behavioral Sciences
- Center for Psychedelic and Consciousness Research
| | - Matthew W Johnson
- Department of Psychiatry and Behavioral Sciences
- Center for Psychedelic and Consciousness Research
| | - Roland R Griffiths
- Department of Psychiatry and Behavioral Sciences
- Center for Psychedelic and Consciousness Research
- Department of Neuroscience
| | - Manoj K Doss
- Department of Psychiatry and Behavioral Sciences
- Center for Psychedelic and Consciousness Research
| | - Albert Garcia-Romeu
- Department of Psychiatry and Behavioral Sciences
- Center for Psychedelic and Consciousness Research
| | - Sandeep Nayak
- Department of Psychiatry and Behavioral Sciences
- Center for Psychedelic and Consciousness Research
| | - Natalie Gukasyan
- Department of Psychiatry and Behavioral Sciences
- Center for Psychedelic and Consciousness Research
| | - Brian N Mathur
- Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Frederick S Barrett
- Department of Psychiatry and Behavioral Sciences
- Center for Psychedelic and Consciousness Research
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