Étiquette : neuroimagerie

LSD Increases Primary Process Thinking via Serotonin 2A Receptor Activation, Rainer Kraehenmann et al., 2017

LSD Increases Primary Process Thinking via Serotonin 2A Receptor Activation Rainer Kraehenmann, Dan Pokorny, Helena Aicher, Katrin H. Preller, Thomas Pokorny, Oliver G. Bosch, Erich Seifritz and Franz X. Vollenweider Frontiers in Pharmacology, 2017, Volume 8, Article 814, 1-9. Doi : 10.3389/fphar.2017.00814   Rationale : Stimulation of serotonin 2A (5-HT2A) receptors by lysergic acid diethylamide (LSD) and related compounds such as psilocybin has previously been shown to increase primary process thinking – an ontologically and evolutionary early, implicit, associative, and automatic mode of thinking which is typically occurring during altered states of consciousness such as dreaming. However, it is still largely unknown whether LSD induces [...]

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Psilocybin-Induced Decrease in Amygdala Reactivity Correlates with Enhanced Positive Mood in Healthy Volunteers, Rainer Kraehenmann et al., 2014

Psilocybin-Induced Decrease in Amygdala Reactivity Correlates with Enhanced Positive Mood in Healthy Volunteers Rainer Kraehenmann, Katrin H. Preller, Milan Scheidegger, Thomas Pokorny, Oliver G. Bosch, Erich Seifritz, and Franz X. Vollenweider Biological Psychiatry, 2014. http://dx.doi.org/10.1016/j.biopsych.2014.04.010   Background : The amygdala is a key structure in serotonergic emotion-processing circuits. In healthy volunteers, acute administration of the serotonin 1A/2A/2C receptor agonist psilocybin reduces neural responses to negative stimuli and induces mood changes toward positive states. However, it is little known whether psilocybin reduces amygdala reactivity to negative stimuli and whether any change in amygdala reactivity is related to mood change. Methods : This study assessed the effects of [...]

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Prolonged Cannabidiol Treatment Effects on Hippocampal Subfield Volumes in Current Cannabis Users, Camilla Beale et al., 2018

Prolonged Cannabidiol Treatment Effects on Hippocampal Subfield Volumes in Current Cannabis Users Camilla Beale, Samantha J. Broyd, Yann Chye, Chao Suo, Mark Schira, Peter Galettis, Jennifer H. Martin, Murat Yücel and Nadia Solowij Cannabis and Cannabinoid Research, 2018, 3, 1, 94-107. Doi : 10.1089/can.2017.0047 Abstract Introduction : Chronic cannabis use is associated with neuroanatomical alterations in the hippocampus. While adverse impacts of cannabis use are generally attributed to D9 tetrahydro-cannabinol, emerging naturalistic evidence suggests cannabidiol (CBD) is neuroprotective and may ameliorate brain harms associated with cannabis use, including protection from hippocampal volume loss. This study examined whether prolonged administration of CBD to regular cannabis users [...]

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Cannabis Use in Adolescence : A Review of Neuroimaging Findings, Yann Chye et al., 2019

Cannabis Use in Adolescence : A Review of Neuroimaging Findings Yann Chye, Erynn Christensen & Murat Yücel Journal of Dual Diagnosis, 2019 Doi : 10.1080/15504263.2019.1636171   ABSTRACT Objective : Shifting policies and widespread acceptance of cannabis for medical and/or recreational purposes have fueled worries of increased cannabis initiation and use in adolescents. In particular, the adolescent period is thought to be associated with an increased susceptibility to the potential harms of repeated cannabis use, due to being a critical period for neuromaturational events in the brain. This review investigates the neuroimaging evidence of brain harms attributable to adolescent cannabis use. Methods : PubMed and Scopus searches were [...]

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Neuroanatomical alterations in people with high and low cannabis dependence, Valentina Lorenzetti et al., 2019

Neuroanatomical alterations in people with high and low cannabis dependence Valentina Lorenzetti, Yann Chye, Chao Suo, Mark Walterfang, Dan I Lubman, Michael Takagi, Sarah Whittle, Antonio Verdejo-Garcia, Janna Cousijn, Christos Pantelis, Marc Seal, Alex Fornito, Murat Yücel and Nadia Solowij Australian & New Zealand Journal of Psychiatry, 2019, 1–8 https://doi.org/10.1177/0004867419859077   Abstract Objectives : We aimed to investigate whether severity of cannabis dependence is associated with the neuroanatomy of key brain regions of the stress and reward brain circuits. Methods : To examine dependence-specific regional brain alterations, we compared the volumes of regions relevant to reward and stress, between high-dependence cannabis users (CD+, n = 25), low [...]

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Cortical surface morphology in long-term cannabis users : A multi-site MRI study, Yann Chye et al., 2018

Cortical surface morphology in long-term cannabis users : A multi-site MRI study Yann Chye, Chao Suo, Valentina Lorenzetti, Albert Batalla, Janna Cousijn, Anna E Goudriaan, Rocio Martin-Santos, Sarah Whittle, Nadia Solowij, Murat Yücel European Neuropsychopharmacology, 2018, 17, 21, 1-9. https://doi.org/10.1016/j.euroneuro.2018.11.1110   Abstract Cannabis exerts its psychoactive effect through cannabinoid receptors that are widely distributed across the cortical surface of the human brain. It is suggested that cannabis use may contribute to structural alterations across the cortical surface. In a large, multisite dataset of 120 controls and 141 cannabis users, we examined whether differences in key characteristics of the cortical surface – including cortical thickness, surface area, [...]

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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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The Role of MDMA Neurotoxicity in Anxiety, Casey R. Guillot et al., 2007

The Role of MDMA Neurotoxicity in Anxiety Casey R. Guillot, Mitchell E. Berman and Brenton R. Abadie In : Neurotoxicity Syndromes, Chapter I ISBN: 978-1-60021-797-5 Editor: Linda R. Webster, pp. 1 - 36 © 2007 Nova Science Publishers, Inc. Abstract The drug 3,4-methylenedioxymethamphetamine (MDMA; Ecstasy) long has been considered a neurotoxin selective for serotonin (5-hydroxytryptamine; 5-HT) axons in rats and nonhuman primates. MDMA is also thought to have the potential to cause persistent serotonergic alterations in humans. Since the serotonin system is involved in the regulation of anxiety, researchers have proposed that recreational Ecstasy users may be at risk for the development of anxiety disorders and symptoms. [...]

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Acute effects of delta 9-tetrahydrocannabinol (THC) on resting state brain function and their modulation by COMT genotype, Matthijs G. Bossong et al., 2019

Acute effects of delta-9-tetrahydrocannabinol (THC) on resting state brain function and their modulation by COMT genotype Matthijs G. Bossong, Hendrika H. van Hell, Chris D. Schubart, Wesley van Saane, Tabitha A. Iseger, Gerry Jager, Matthias J.P. van Osch, J. Martijn Jansma, René S. Kahn, Marco P. Boks, Nick F. Ramsey European Neuropsychopharmacology, 2019, 13, 56, 1–11 https://doi.org/10.1016/j.euroneuro.2019.03.010   Abstract Cannabis produces a broad range of acute, dose-dependent psychotropic effects. Only a limited number of neuroimaging studies have mapped these effects by examining the impact of cannabis on resting state brain neurophysiology. Moreover, how genetic variation influences the acute effects of cannabis on resting state brain function [...]

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The neuropsychopharmacology of cannabis : A review of human imaging studies, Michael A.P. Bloomfield et al., 2019

The neuropsychopharmacology of cannabis : A review of human imaging studies Michael A.P. Bloomfield, Chandni Hindocha, Sebastian F. Green, Matthew B.Wall, Rachel Lees, Katherine Petrilli, Harry Costello, M. Olabisi Ogunbiyi, Matthijs G. Bossong, Tom P. Freeman Pharmacology & Therapeutics, 2019, 195, 132-161 doi : 10.1016/j.pharmthera.2018.10.006 a b s t r a c t The laws governing cannabis are evolving worldwide and associated with changing patterns of use. The main psychoactive drug in cannabis is Δ9-tetrahydrocannabinol (THC), a partial agonist at the endocannabinoid CB1 receptor. Acutely, cannabis and THC produce a range of effects on several neurocognitive and pharmacological systems. These include effects on executive, emotional, [...]

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