Schizotypy and psychosis-like experiences from recreational cannabis in a non-clinical sample Emma Barkus, Shon Lewis Psychological Medicine, 2008, 38, 1267-1276. doi:10.1017/S0033291707002619 Research On Line, University of Wollongong, 2008 Copyright Cambridge University Press. Abstract Background : The relationship between cannabis use and psychosis is still a matter for debate. Accounting for the individual differences in subjective experiences to recreational cannabis use in the general population may hold some clues to the aetiological relationship between cannabis and psychotic symptoms. We hypothesized that schizotypy would account for the individual differences in subjective experiences after cannabis use but not in patterns of use. Method : In a sample of 532 young people [...]
Lire la suiteCannabis-induced psychosis-like experiences are associated with high schizotypy BARKUS E.J., STIRLING J., HOPKINS R.S., LEWIS S. Psychopathology, 2006, 39, 4, 175-178 PMID : 16636640 DOI : 10.1159/000092678 Abstract OBJECTIVE: Recent studies have suggested that cannabis use is a risk factor for developing schizophrenia. We tested the hypothesis that cannabis use increases the likelihood of psychosis-like experiences in non-clinical participants who scored highly on a measure of schizotypy. METHOD: The psychological effects of cannabis were assessed in 137 healthy individuals (76% female, mean age 22 years) using a newly developed questionnaire concerned with subjective experiences of the drug: the Cannabis Experiences Questionnaire. The questionnaire has three subscales: Pleasurable [...]
Lire la suiteEffects of delta-9-tetrahydrocannabinol on evaluation of emotional images Michael E Ballard, Gillinder Bedi, and Harriet de Wit Journal of Psychopharmacology, 2012, 26, 10, 1289–1298. doi:10.1177/0269881112446530. Abstract There is growing evidence that drugs of abuse alter processing of emotional information in ways that could be attractive to users. Our recent report that Δ9-tetrahydrocannabinol (THC) diminishes amygdalar activation in response to threat-related faces suggests that THC may modify evaluation of emotionally-salient, particularly negative or threatening, stimuli. In this study, we examined the effects of acute THC on evaluation of emotional images. Healthy volunteers received two doses of THC (7.5 and 15 mg; p.o.) and placebo across separate [...]
Lire la suiteAcute effects of delta-9-tetrahydrocannabinol, cannabidiol and their combination on facial emotion recognition: A randomised, double-blind, placebo-controlled study in cannabis users Chandni Hindocha, Tom P. Freeman, Grainne Schafer, Chelsea Gardener, Ravi K. Das, Celia J.A. Morgan and H. Valerie Curran Eur Neuropsychopharmacology, 2015, 25, 3, 325–334. doi:10.1016/j.euroneuro.2014.11.014 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4398332/?report=printable Abstract Acute administration of the primary psychoactive constituent of cannabis, Δ-9-tetrahydrocannabinol (THC), impairs human facial affect recognition, implicating the endocannabinoid system in emotional processing. Another main constituent of cannabis, cannabidiol (CBD), has seemingly opposite functional effects on the brain. This study aimed to determine the effects of THC and CBD, both alone and in combination on emotional facial affect [...]
Lire la suiteClinical and Preclinical Evidence for Functional Interactions of Cannabidiol and Δ9-Tetrahydrocannabinol Douglas L. Boggs, Jacques D. Nguyen, Daralyn Morgenson, Michael A. Taffe and and Mohini Ranganathan Neuropsychopharmacology, 2018, 43, 142-154 Doi : 10.1038/npp.2017.209; published online 18 October 2017 Abstract The plant Cannabis sativa, commonly called cannabis or marijuana, has been used for its psychotropic and mind-altering side effects for millennia. There has been growing attention in recent years on its potential therapeutic efficacy as municipalities and legislative bodies in the United States, Canada, and other countries grapple with enacting policy to facilitate the use of cannabis or its constituents for medical purposes. There are >550 [...]
Lire la suiteOpposite Effects of Δ-9-Tetrahydrocannabinol and Cannabidiol on Human Brain Function and Psychopathology Sagnik Bhattacharyya, Paul D Morrison,
Lire la suiteWhich biological and self-report measures of cannabis use predict cannabis dependency and acute psychotic-like effects ? H. Valerie Curran, Chandni Hindocha, Celia J. A. Morgan, Natacha Shaban, Ravi K. Das and Tom P. Freeman Psychological Medicine, 2018, 1-7. https://doi.org/10.1017/S003329171800226X Abstract Background : Changes in cannabis regulation globally make it increasingly important to determine what predicts an individual’s risk of experiencing adverse drug effects. Relevant studies have used diverse self-report measures of cannabis use, and few include multiple biological measures. Here we aimed to determine which biological and self-report measures of cannabis use predict cannabis dependency and acute psychotic-like symptoms. Method : In a naturalistic study, 410 [...]
Lire la suiteCannabidiol inhibits THC-elicited paranoid symptoms and hippocampal-dependent memory impairment Amir Englund, Paul D Morrison, Judith Nottage, Dominic Hague, Fergus Kane1, Stefania Bonaccorso1, James M Stone, Avi Reichenberg, Rudolf Brenneisen, David Holt, Amanda Feilding, Lucy Walker, Robin M Murray and Shitij Kapur Journal of Psychopharmacology, 2012 Doi : 10.1177/0269881112460109 Abstract Community-based studies suggest that cannabis products that are high in Δ9-tetrahydrocannabinol (THC) but low in cannabidiol (CBD) are particularly hazardous for mental health. Laboratory-based studies are ideal for clarifying this issue because THC and CBD can be administered in pure form, under controlled conditions. In a between-subjects design, we tested the hypothesis that pre-treatment with CBD inhibited [...]
Lire la suiteCannabidiol enhances anandamide signaling and alleviates psychotic symptoms of schizophrenia F. M. Leweke, D. Piomelli, F. Pahlisch, D. Muhl, C.W. Gerth, C. Hoyer, J. Klosterkötter, M. Hellmich and D. Koethe Translationnal Psychiatry, 2012, 2, e94 doi :10.1038/tp.2012.15; published online 20 March 2012 Abstract Cannabidiol is a component of marijuana that does not activate cannabinoid receptors, but moderately inhibits the degradation of the endocannabinoid anandamide. We previously reported that an elevation of anandamide levels in cerebrospinal fluid inversely correlated to psychotic symptoms. Furthermore, enhanced anandamide signaling let to a lower transition rate from initial prodromal states into frank psychosis as well as postponed transition. In [...]
Lire la suiteMultiple mechanisms involved in the large-spectrum therapeutic potential of cannabidiol in psychiatric disorders Alline Cristina Campos, Fabricio Araujo Moreira, Felipe Villela Gomes, Elaine Aparecida Del Bel and Francisco Silveira Guimaraes Philosophical Transactions of The Royal Society Bulletin, 2012, 367, 3364–3378 doi:10.1098/rstb.2011.0389 Abstract Cannabidiol (CBD) is amajor phytocannabinoid present in the Cannabis sativa plant. It lacks the psychotomimetic and other psychotropic effects that the main plant compound D9 tetrahydrocannabinol (THC) being able, on the contrary, to antagonize these effects. This property, together with its safety profile, was an initial stimulus for the investigation of CBD pharmacological properties. It is now clear thatCBDhas therapeutic potential over a [...]
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