Étiquette : fMRI

Bridging the Gap ? Altered Thalamocortical Connectivity in Psychotic and Psychedelic States, Mihai Avram et al., 2021

Bridging the Gap ? Altered Thalamocortical Connectivity in Psychotic and Psychedelic States Mihai Avram, Helena Rogg, Alexandra Korda, Christina Andreou, Felix Müller and Stefan Borgwardt Frontiers in Psychiatry, 2021, Volume 12, Article 706017, 1-13. Doi : 10.3389/fpsyt.2021.706017   Psychiatry has a well-established tradition of comparing drug-induced experiences to psychotic symptoms, based on shared phenomena such as altered perceptions. The present review focuses on experiences induced by classic psychedelics, which are substances capable of eliciting powerful psychoactive effects, characterized by distortions/alterations of several neurocognitive processes (e.g., hallucinations). Herein we refer to such experiences as psychedelic states. Psychosis is a clinical syndrome defined by impaired reality testing, [...]

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The Impact of Cannabidiol on Human Brain Function : A Systematic Review, Albert Batalla et al., 2021

The Impact of Cannabidiol on Human Brain Function : A Systematic Review Albert Batalla, Julian Bos, Amber Postma and Matthijs G. Bossong Frontiers in Pharmacology, January 2021 | Volume 11 | Article 618184, 1-15. doi : 10.3389/fphar.2020.618184   Background : Accumulating evidence suggests that the non-intoxicating cannabinoid compound cannabidiol (CBD) may have antipsychotic and anxiolytic properties, and thus may be a promising new agent in the treatment of psychotic and anxiety disorders. However, the neurobiological substrates underlying the potential therapeutic effects of CBD are still unclear. The aim of this systematic review is to provide a detailed and up-todate systematic literature overview of neuroimaging studies [...]

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The effect of cannabidiol (CBD) on low-frequency activity and functional connectivity in the brain of adults with and without autism spectrum disorder (ASD), Charlotte M Pretzsch et al., 2019

The effect of cannabidiol (CBD) on low-frequency activity and functional connectivity in the brain of adults with and without autism spectrum disorder (ASD) Charlotte M. Pretzsch, Bogdan Voinescu, Maria A. Mendez, Robert Wichers, Laura Ajram, Glynis Ivin, Martin Heasman, Steven Williams, Declan GM Murphy, Eileen Daly and Gráinne M. McAlonan Journal of Psychopharmacology, 2019, Vol. 33, (9), 1141–1148 Doi : 10.1177/0269881119858306   Abstract Background : The potential benefits of cannabis and its major non-intoxicating component cannabidiol (CBD) are attracting attention, including as a potential treatment in neurodevelopmental disorders such as autism spectrum disorder (ASD). However, the neural action of CBD, and its relevance to ASD, remains [...]

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Cannabidiol has a unique effect on global brain activity: a pharmacological, functional MRI study in awake mice, Aymen H. Sadaka et al., 2021

Cannabidiol has a unique effect on global brain activity: a pharmacological, functional MRI study in awake mice Aymen H. Sadaka, Ana G. Ozuna1, Richard J. Ortiz, Praveen Kulkarni, Clare T. Johnson, Heather B. Bradshaw, Bruce S. Cushing, Ai‑Ling Li, Andrea G. Hohmann and Craig F. Ferris Journal of Translationnal Medicine, 2021, 19, 220, 1-16. Doi : 10.1186/s12967-021-02891-6   Abstract Background : The phytocannabinoid cannabidiol (CBD) exhibits anxiolytic activity and has been promoted as a potential treatment for post-traumatic stress disorders. How does CBD interact with the brain to alter behavior? We hypothesized that CBD would produce a dose-dependent reduction in brain activity and functional coupling in [...]

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Psilocybin for treatment-resistant depression : fMRI-measured brain mechanisms, Robin L. Carhart-Harris et al., 2017

Psilocybin for treatment-resistant depression : fMRI-measured brain mechanisms Robin L Carhart-Harris, Leor Roseman, Mark Bolstridge, Lysia Demetriou, J Nienke Pannekoek, Matthew B Wall, Mark Tanner, Mendel Kaelen, John McGonigle, Kevin Murphy, Robert Leech, H Valerie Curran & David J Nutt Nature, Scientific Reports, 2017, 7, 13187 |1-11 Doi : 10.1038/s41598-017-13282-7   Abstract Psilocybin with psychological support is showing promise as a treatment model in psychiatry but its therapeutic mechanisms are poorly understood. Here, cerebral blood flow (CBF) and blood oxygen-level dependent (BOLD) resting-state functional connectivity (RSFC) were measured with functional magnetic resonance imaging (fMRI) before and after treatment with psilocybin (serotonin agonist) for treatment-resistant depression (TRD). [...]

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‘Magic Mushrooms’ Effective for Severe Depression, Batya Swift Yasgur, medscape.com, 2017

'Magic Mushrooms' Effective for Severe Depression Batya Swift Yasgur, MA, LSW Medscape Medical News © 2017 October 20, 2017   Psilocybin, the psychoactive compound in “magic mushrooms,” is a promising intervention for patients with treatment-resistant depression (TRD) and appears to offer a rapid, sustained effect, new research shows. Investigators led by David Nutt, MD, PhD, professor of neuropsychopharmacology, Imperial College, London, United Kingdom, collected pre- and posttreatment fMRI data on the use of psilocybin in 19 patients with severe major depression who had failed to respond to conventional treatments. The patients experience dramatic improvements in depressive symptoms 1 day following treatment; close to half met criteria for full response at 5 [...]

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Neural Mechanisms for the Cannabinoid Modulation of Cognition and Affect in Man : A Critical Review of Neuroimaging Studies, Sagnik Bhattacharyya et al., 2012,

Neural Mechanisms for the Cannabinoid Modulation of Cognition and Affect in Man : A Critical Review of Neuroimaging Studies Sagnik Bhattacharyya, Zerrin Atakan, Rocio Martin-Santos, Jose A. Crippa and Philip K. McGuire Current Pharmaceutical Design, 2012, 18, 5045-5054   Abstract Pharmacological challenge in conjunction with neuroimaging techniques has been employed for over two decades now to understand the neural basis of the cognitive, emotional and symptomatic effects of the main ingredients of cannabis, the most widely used illicit drug in the world. This selective critical review focuses on the human neuroimaging studies investigating the effects of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), the two main cannabinoids [...]

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Dynamic coupling of whole-brain neuronal and neurotransmitter systems, Morten L. Kringelbach et al., 2020

Dynamic coupling of whole-brain neuronal and neurotransmitter systems Morten L. Kringelbach, Josephine Cruzat, Joana Cabral, Gitte Moos Knudsen, Robin Carhart-Harris, Peter C. Whybrow Nikos K. Logothetis, and Gustavo Deco PNAS, 2020, 1-11 doi : 10.1073/pnas.1921475117   Remarkable progress has come from whole-brain models linking anatomy and function. Paradoxically, it is not clear how a neuronal dynamical system running in the fixed human anatomical connectome can give rise to the rich changes in the functional repertoire associated with human brain function, which is impossible to explain through long-term plasticity. Neuromodulation evolved to allow for such flexibility by dynamically updating the effectivity of the fixed anatomical connectivity. [...]

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Psychedelics for Mental Illness: The Evidence to Date, Todd Murphy, 2020

Psychedelics for Mental Illness: The Evidence to Date Todd Murphy Medscape, 12 March, 2020. https://www.medscape.com/viewarticle/926694_print Psychedelic drugs show real promise as treatment for psychiatric illnesses, particularly posttraumatic stress disorder (PTSD) as well as depression and anxiety, new research suggests. A literature review showed completed clinical trials support the efficacy of 3, 4-methylenedioxymethamphetamine (MDMA), commonly known by its street name of Ecstasy, to treat chronic PTSD. The review also confirmed that psilocybin, a compound contained in some species of mushrooms, significantly helped in the treatment of depression and cancer-related anxiety. Other promising, though more preliminary, results suggests that the hallucinogenic drug LSD (lysergic acid diethylamide) and a plant-based brew [...]

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Serotonin 2A Receptor Signaling Underlies LSDinduced Alteration of the Neural Response to Dynamic Changes in Music, Frederick S. Barrett et al., 2018

Serotonin 2A Receptor Signaling Underlies LSD-induced Alteration of the Neural Response to Dynamic Changes in Music Frederick S. Barrett, Katrin H. Preller, Marcus Herdener, Petr Janata and Franz X. Vollenweider Cerebral Cortex, November 2018, 28, 3939–3950. doi : 10.1093/cercor/bhx257   Abstract Classic psychedelic drugs (serotonin 2A, or 5HT2A, receptor agonists) have notable effects on music listening. In the current report, blood oxygen level-dependent (BOLD) signal was collected during music listening in 25 healthy adults after administration of placebo, lysergic acid diethylamide (LSD), and LSD pretreated with the 5HT2A antagonist ketanserin, to investigate the role of 5HT2A receptor signaling in the neural response to the time-varying tonal [...]

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