Étiquette : fMRI

Increased amygdala responses to emotional faces after psilocybin for treatment-resistant depression, Leor Roseman et al., 2018

Increased amygdala responses to emotional faces after psilocybin for treatment-resistant depression Leor Roseman, Lysia Demetriou, Matthew B. Wall, David J. Nutt, Robin L. Carhart-Harris Neuropharmacology, 2018, 142, 263e269. https://doi.org/10.1016/j.neuropharm.2017.12.041   Abstract Recent evidence indicates that psilocybin with psychological support may be effective for treating depression. Some studies have found that patients with depression show heightened amygdala responses to fearful faces and there is reliable evidence that treatment with SSRIs attenuates amygdala responses (Ma, 2015). We hypothesised that amygdala responses to emotional faces would be altered post treatment with psilocybin. In this open-label study, 20 individuals diagnosed with moderate to severe, treatment-resistant depression, underwent two separate dosing [...]

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The Effects of Acutely Administered 3,4-Methylenedioxymethamphetamine on Spontaneous Brain Function in Healthy Volunteers Measured with Arterial Spin Labeling and Blood Oxygen Level–Dependent Resting State Functional Connectivity, Robin L. Carhart-Harris et al., 2015

The Effects of Acutely Administered 3,4-Methylenedioxymethamphetamine on Spontaneous Brain Function in Healthy Volunteers Measured with Arterial Spin Labeling and Blood Oxygen Level–Dependent Resting State Functional Connectivity Robin L. Carhart-Harris, Kevin Murphy, Robert Leech, David Erritzoe, Matthew B. Wall, Bart Ferguson, Luke T.J. Williams, Leor Roseman, Stefan Brugger, Ineke De Meer, Mark Tanner, Robin Tyacke, Kim Wolff, Ajun Sethi, Michael A.P. Bloomfield, Tim M. Williams, Mark Bolstridge, Lorna Stewart, Celia Morgan, Rexford D. Newbould, Amanda Feilding, H. Val Curran, and David J. Nutt Biological Psychiatry, 2015, 78, 554-562. http://dx.doi.org/10.1016/j.biopsych.2013.12.015   ABSTRACT BACKGROUND : The compound 3,4-methylenedioxymethamphetamine (MDMA) is a potent monoamine releaser that produces an acute euphoria in most individuals. METHODS : [...]

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Receptor-Enriched Analysis of functional connectivity by targets (REACT) : A novel, multimodal analytical approach informed by PET to study the pharmacodynamic response of the brain under MDMA, Ottavia Dipasquale et al., 2019

Receptor-Enriched Analysis of functional connectivity by targets (REACT) : A novel, multimodal analytical approach informed by PET to study the pharmacodynamic response of the brain under MDMA Ottavia Dipasquale, Pierluigi Selvaggi, Mattia Veronese, Anthony S. Gabay, Federico Turkheimer, Mitul A. Mehta NeuroImage, 2019, 195, 252–260 https://doi.org/10.1016/j.neuroimage.2019.04.007   A B S T R A C T One of the main limitations of pharmacological fMRI is its inability to provide a molecular insight into the main effect of compounds, leaving an open question about the relationship between drug effects and haemodynamic response. The aim of this study is to investigate the acute effects of 3,4-methylene-dioxymethamphetamine (MDMA) on functional [...]

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Psilocybin exerts distinct effects on resting state networks 1 associated with serotonin and dopamine in mice, Joanes Grandjean et al., 2019

Psilocybin exerts distinct effects on resting state networks 1 associated with serotonin and dopamine in mice Joanes Grandjean, David Buehlmann, Michaela Buerge, Hannes Sigrist, Erich Seifritz, Franz X. Vollenweider, Christopher R. Pryce, Markus Rudin Preprint · September 2019 Doi : 10.1101/751255   Abstract Hallucinogenic agents have been proposed as potent antidepressants; this includes the serotonin (5-HT) receptor 2A agonist psilocybin. In human subjects, psilocybin alters functional connectivity (FC) within the default-mode network (DMN), a constellation of inter-connected regions that is involved in self-reference and displays altered FC in depressive disorders. In this study we investigated the effects of psilocybin on FC in the analogue of the [...]

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Psilocybine mindfulness training modulates self-consciousness and brain default mode network connectivity with lasting effects, SMIGIELSKI Lukasz et al., 2019

Psilocybine mindfulness training modulates self-consciousness and brain default mode network connectivity with lasting effects SMIGIELSKI Lukasz, SCHEIDEGGER Milan, KOMETER Michael, VOLLENWEIDER Franz X. NeuroImage, 2019, 196, 207-215 Doi : 10.1016/j.neuroimage.2019.04.009   A B S T R A C T Both psychedelics and meditation exert profound modulatory effects on consciousness, perception and cognition, but their combined, possibly synergistic effects on neurobiology are unknown. Accordingly, we conducted a randomized, double-blind, placebo-controlled study with 38 participants following a single administration of the psychedelic psilocybin (315 μg/kg p.o.) during a 5-day mindfulness retreat. Brain dynamics were quantified directly pre- and post-intervention by functional magnetic resonance imaging during the resting state and [...]

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The administration of psilocybin to healthy, hallucinogen-experienced volunteers in a mock-functional magnetic resonnance imaging environment : a preliminary investigation of tolerability, Robin L. Carhart-Harris et al., 2010

The administration of psilocybin to healthy, hallucinogen-experienced volunteers in a mock-functional magnetic resonnance imaging environment : a preliminary investigation of tolerability Robin L. Carhart-Harris et al., Journal of Psychopharmacology, 2010, 1-6 DOI: 10.1177/0269881110367445   Abstract This study sought to assess the tolerability of intravenously administered psilocybin in healthy, hallucinogen-experienced volunteers in a mock-magnetic resonance imaging environment as a preliminary stage to a controlled investigation using functional magnetic resonance imaging to explore the effects of psilocybin on cerebral blood flow and activity. The present pilot study demonstrated that up to 2 mg of psilocybin delivered as a slow intravenous injection produces short-lived but typical drug effects that [...]

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Implications for psychedelic-assisted psychotherapy : functional magnetic resonnance imaging study with psilocybin, Robin L. Carhart-Harris et al., 2012

Implications for psychedelic-assisted psychotherapy : a functional magnetic resonance imaging study with psilocybin R. L. Carhart-Harris, R. Leech, T. M. Williams, D. Erritzoe, N. Abbasi, T. Bargiotas, P. Hobden, D. J. Sharp, J. Evans, A. Feilding, R. G. Wise and D. J. Nutt British Journal of Psychiatry, 2012, 200, 238-244. Doi : 10.1192/bjp.bp.111.103309   Background Psilocybin is a classic psychedelic drug that has a history of use in psychotherapy. One of the rationales for its use was that it aids emotional insight by lowering psychological defences. Aims To test the hypothesis that psilocybin facilitates access to personal memories and emotions by comparing subjective and neural responses to positive [...]

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Functional Connectivity Measures After Psilocybin Inform a Novel Hypothesis of Early Psychosis, Robin L. Carhart-Harris et al., 2012

Functional Connectivity Measures After Psilocybin Inform a Novel Hypothesis of Early Psychosis Robin L. Carhart-Harris, Robert Leech, David Erritzoe, Tim M. Williams, James M. Stone, John Evans, David J. Sharp, Amanda Feilding, Richard G. Wise, and David J. Nutt Schizophrenia Bulletin, 2012, Volume 39, Issue 6, November 2013, Pages 1343–1351 doi : 10.1093/schbul/sbs117   Psilocybin is a classic psychedelic and a candidate drug model of psychosis. This study measured the effects of psilocybin on resting-state network and thalamo-cortical functional connectivity (FC) using functional magnetic resonance imaging (fMRI). Fifteen healthy volunteers received intravenous infusions of psilocybin and placebo in 2 task-free resting-state scans. Primary analyses focused on [...]

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Neural correlates of the psychedelic state as determined by fMRI studies with psilocybine, Robin L. Carhart-Harris et al., 2012

Neural correlates of the psychedelic state as determined by fMRI studies with psilocybine Robin L. Carhart-Harris, David Erritzoe, Tim Williams, James M. Stone, Laurence J. Reed, Alessandro Colasanti, Robin J. Tyacke, Robert Leech, Andrea L. Malizia, Kevin Murphy, Peter Hobden, John Evans, Amanda Feilding, Richard G. Wise, and David J. Nutt PNAS, Proceedings of the National Academy of Sciences of the USA, 2012, 109, (6), 2138-2143. doi:10.1073/pnas.1119598109 www.pnas.org/lookup/suppl/doi:10.1073/pnas.1119598109/-/DCSupplemental.   Abstract Psychedelic drugs have a long history of use in healing ceremonies, but despite renewed interest in their therapeutic potential, we continue to know very little about howthey work in the brain. Here we used psilocybin, a classic [...]

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Homological scaffolds of brain functional networks, G. Petri et al.,2014

Homological scaffolds of brain functional networks G. Petri, Paul Expert, F. Turkheimer, Robin Carhart-Harris, David Nutt, P.J. hellyer, F. Vaccarino Journal of The Royal Society, Interface, 2014, 11, 20140873 Published : 06 December 2014 https://doi.org/10.1098/rsif.2014.0873 Abstract Networks, as efficient representations of complex systems, have appealed to scientists for a long time and now permeate many areas of science, including neuroimaging (Bullmore and Sporns 2009 Nat. Rev. Neurosci.10, 186–198. (doi:10.1038/nrn2618)). Traditionally, the structure of complex networks has been studied through their statistical properties and metrics concerned with node and link properties, e.g. degree-distribution, node centrality and modularity. Here, we study the characteristics of functional brain networks at [...]

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