Étiquette : fMRI

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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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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The mixed serotonin receptor agonist psilocybin reduces threat-induced modulation of amygdala connectivity, Rainer Kraehenmann et al., 2016

The mixed serotonin receptor agonist psilocybin reduces threat-induced modulation of amygdala connectivity Rainer Kraehenmann, André Schmidt, Karl Friston, Katrin H. Preller, Erich Seifritz, Franz X. Vollenweider NeuroImage : Clinical, 2016, 11, 53–60 http://dx.doi.org/10.1016/j.nicl.2015.08.009   a b s t r a c t Stimulation of serotonergic neurotransmission by psilocybin has been shown to shift emotional biases away from negative towards positive stimuli. We have recently shown that reduced amygdala activity during threat processing might underlie psilocybin's effect on emotional processing. However, it is still not known whether psilocybin modulates bottom-up or top-down connectivity within the visual-limbic-prefrontal network underlying threat processing.We therefore analyzed our previous fMRI data using [...]

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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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Modulation of Social Cognition via Hallucinogens and “Entactogens”, Katrin H. Preller and Franz X. Vollenweider, 2019

Modulation of Social Cognition via Hallucinogens and “Entactogens” Katrin H. Preller and Franz X. Vollenweider Frontiers in Psychiatry, décembre 2019 doi: 10.3389/fpsyt.2019.00881 Social cognition is a fundamental ability in human everyday lives. Deficits in social functioning also represent a core aspect of many psychiatric disorders. Yet, despite its significance, deficits in social cognition skills are insufficiently targeted by current treatments. Hallucinogens and entactogens have been shown to have the potential to modulate social processing. This article reviews the literature on the influence of hallucinogens and entactogens on social processing in controlled experimental studies in humans and elucidates the underlying neurobiological and neuropharmacological mechanisms. Furthermore, [...]

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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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Adolescent Cannabis Use : What is the Evidence for Functional Brain Alteration ?, V. Lorenzetti et al., 2016

Adolescent Cannabis Use : What is the Evidence for Functional Brain Alteration ? V. Lorenzetti, S. Alonso-Lanaa, G. J. Youssef, A. Verdejo-Garcia, C. Suo, J. Cousijn, M. Takagi, M. Yücel and N. Solowij Current Pharmaceutical Design, 2016, 22, 1-14. DOI: 10.2174/1381612822666160805155922   Abstract Background : Cannabis use typically commences during adolescence, a period during which the brain undergoes profound remodeling in areas that are high in cannabinoid receptors and that mediate cognitive control and emotion regulation. It is therefore important to determine the impact of adolescent cannabis use on brain function. Objective : We investigate the impact of adolescent cannabis use on brain function by reviewing the functional [...]

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Does regular cannabis use affect neuroanatomy ? An updated systematic review and meta-analysis of structural neuroimaging studies, Valentina Lorenzetti et al., 2019

Does regular cannabis use affect neuroanatomy ? An updated systematic review and meta-analysis of structural neuroimaging studies Valentina Lorenzetti, Yann Chye, Pedro Silva, Nadia Solowij, Carl A. Roberts European Archives of Psychiatry and Clinical Neuroscience, 2019 Doi : 10.1007/s00406-019-00979-1 Abstract Regular cannabis use is associated with adverse cognitive and mental health outcomes that have been ascribed to aberrant neuroanatomy in brain regions densely innervated with cannabinoid receptors. Neuroanatomical differences between cannabis users and controls have been assessed in multiple structural magnetic resonance imaging (sMRI) studies. However, there is heterogeneity in the results leading to cautious interpretation of the data so far. We examined the sMRI [...]

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