Étiquette : neurophysiologie

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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The Role of Cannabis within an Emerging Perspective on Schizophrenia, Jegason P. Diviant et al., 2018

The Role of Cannabis within an Emerging Perspective on Schizophrenia Jegason P. Diviant, Jacob M. Vigil, and Sarah S. Stith Medicines, 2018, 5, 86, 1-11. doi : 10.3390/medicines5030086   Abstract Background : Approximately 0.5% of the population is diagnosed with some form of schizophrenia, under the prevailing view that the pathology is best treated using pharmaceutical medications that act on monoamine receptors. Methods : We briefly review evidence on the impact of environmental forces, particularly the effect of autoimmune activity, in the expression of schizophrenic profiles and the role of Cannabis therapy for regulating immunological functioning. Results : A review of the literature shows that phytocannabinoid consumption may [...]

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The effects of microdose LSD on time perception: a randomised, double-blind, placebo-controlled trial, Steliana Yanakieva et al., 2018

The effects of microdose LSD on time perception: a randomised, double-blind, placebo-controlled trial Steliana Yanakieva, Naya Polychroni, Neiloufar Family, Luke T. J. Williams, David P. Luke & Devin B. Terhune Psychopharmacology, 2018, 1-12. https://doi.org/10.1007/s00213-018-5119-x   Abstract Rationale : Previous research demonstrating that lysergic acid diethylamide (LSD) produces alterations in time perception has implications for its impact on conscious states and a range of psychological functions that necessitate precise interval timing. However, interpretation of this research is hindered by methodological limitations and an inability to dissociate direct neurochemical effects on interval timing from indirect effects attributable to altered states of consciousness. Methods : We conducted a randomised, double-blind, [...]

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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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Cannabinoid-Based Therapies and Brain Development : Potential Harmful Effect of Early Modulation of the Endocannabinoid System, Patrícia Schonhofen et al., 2018

Cannabinoid-Based Therapies and Brain Development : Potential Harmful Effect of Early Modulation of the Endocannabinoid System Patrícia Schonhofen, Ivi Juliana Bristot, José Alexandre Crippa, Jaime Eduardo Cecílio Hallak, Antônio Waldo Zuardi, Richard B. Parsons, Fábio Klamt CNS Drugs, 2018, 32, (Suppl 1), 1-16. Springer Nature Switzerland, Doi : 10.1007/s40263-018-0550-4 Abstract The endocannabinoid retrograde signaling pathway is widely expressed in the central nervous system, where it plays major roles in regulating synaptic plasticity (excitatory and inhibitory) through long-term potentiation and long-term depression. The endocannabinoid system (ECS) components—cannabinoid receptors, endocannabinoids and synthesis/degradation enzymes—are expressed and are functional from early developmental stages and throughout adolescent cortical development, regulating progenitor [...]

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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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Effects of endocannabinoid neurotransmission modulators on brain stimulation reward, Styliani Vlachou et al., 2006

Effects of endocannabinoid neurotransmission modulators on brain stimulation reward Styliani Vlachou, George G. Nomikos & George Panagis Psychopharmacology, 2006, 188, 293–305 Doi : 10.1007/s00213-006-0506-0   Abstract Rationale : The endogenous cannabinoid system is responsive to the neurobiological actions of Δ9-tetrahydrocannabinol (THC) and other cannabinoid ligands. While numerous studies have focused on the behavioral and pharmacological effects of THC and cannabinoid agonists in experimental animals, most recent work focuses on compounds that modulate endocannabinoid neurotransmission. However, the relevant studies concerning the ability of endocannabinoid modulators to modify reward processes in experimental animals remain rather scarce. Objectives : The present study examined the effects of drugs modulating endocannabinoid neurotransmission on [...]

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