Schizophrenia Research
August 2011
Christian D Schubart, Iris E C Sommer, Willemijn A Van Gastel et al.
Cannabis is associated with psychotic outcomes in numerous studies, an effect that is commonly attributed to Δ (9)-tetrahydrocannabinol (Δ 9-THC). An increasing number of authors identify cannabidiol, another component of the cannabis plant, as an antipsychotic agent. The objective of the current study is to investigate the role of cannabidiol content in the association between cannabis use and...
Molecular Psychiatry
July 12, 2011
J. Hirvonen, R. Goodwin, Cheng-Ta Li et al.
Chronic cannabis (marijuana, hashish) smoking can result in dependence. Rodent studies show reversible downregulation of brain cannabinoid CB1 (cannabinoid receptor type 1) receptors after chronic exposure to cannabis. However, whether downregulation occurs in humans who chronically smoke cannabis is unknown. Here we show, using positron emission tomography imaging, reversible and regionally...
Drug and Alcohol Dependence
July 1, 2011
Frances R. Levin, John J Mariani, Daniel J Brooks et al.
Cannabis dependence is a substantial public health problem. Behavioral treatments have shown promise, but there are no effective medications for cannabis dependence. The purpose of this study was to evaluate the safety and efficacy of dronabinol, a synthetic form of delta-9-tetrahydrocannabinol, a naturally occurring pharmacologically active component of marijuana, in treating cannabis...
Drug and Alcohol Dependence
July 1, 2011
Joshua A Lile, Thomas H Kelly, Lon R Hays
Agonist replacement treatment is a promising strategy to manage cannabis-use disorders. The aim of this study was to assess the combined effects of the synthetic cannabinoid agonist nabilone and Δ⁹-tetrahydrocannabinol (Δ⁹-THC) using drug-discrimination procedures, which are sensitive to drug interactions. Testing the concurrent administration of nabilone and Δ⁹-THC was also conducted to...
Neuroimage
July 1, 2011
Andrew P Prescot, Allison E Locatelli, Perry F Renshaw et al.
Converging evidence from neuroimaging and neuropsychological studies indicates that heavy marijuana use is associated with cingulate dysfunction. However, there has been limited human data documenting in vivo biochemical brain changes after chronic marijuana exposure. Previous proton magnetic resonance spectroscopy studies have demonstrated reduced basal ganglia glutamate and dorsolateral...
European Psychiatry
June 28, 2011
Shaul Lev-Ran, Aviv Segev, Yoram Braw et al.
17 citations
This current study assessed neurocognitive functioning in a carefully selected sample of schizophrenia patients with and without heavy cannabis use and healthy controls. All subjects were negative for any other substance use. Schizophrenia subjects had impaired neurocognitive functions across a wide range of tasks compared to healthy controls. Cannabis using schizophrenia patients had focused...
Behavioural Brain Research
June 20, 2011
Melissa P Lopez-Larson, Piotr Bogorodzki, Jadwiga Rogowska et al.
There are limited data regarding the impact of marijuana (MJ) on cortical development during adolescence. Adolescence is a period of substantial brain maturation and cortical thickness abnormalities may be indicative of disruptions of normal cortical development. This investigation applied cortical-surface based techniques to compare cortical thickness measures in MJ using adolescents compared...
Experimental and Clinical Psychopharmacology
June 2011
Staci A Gruber, Marisa M Silveri, Mary Kathryn Dahlgren et al.
Difficulty monitoring and inhibiting impulsive behaviors has been reported in marijuana (MJ) smokers; neuroimaging studies, which examined frontal systems in chronic MJ smokers, have reported alterations during inhibitory tasks. Diffusion tensor imaging (DTI) provides a quantitative estimate of white matter integrity at the microstructural level. We applied DTI, clinical ratings, and...
Neuropsychopharmacology
June 2011
Toby T Winton-Brown, Paul Allen, Sagnik Bhattacharyya et al.
Although the effects of cannabis on perception are well documented, little is known about their neural basis or how these may contribute to the formation of psychotic symptoms. We used functional magnetic resonance imaging (fMRI) to assess the effects of Delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) during visual and auditory processing in healthy volunteers. In total, 14 healthy...
Current Drug Abuse Reviews
June 1, 2011
Sybille Schulz
15 citations
Although the prevalence of co-use of cannabis and 3,4 methylenedioxymethamphetamine (MDMA) is very common among polydrug users in western societies, few studies have tested the consequences on behavior, cognition or neurobiology. This review examines 23 articles published between 2002 and 2010 with an explicit focus on the combination, or administration, of MDMA and cannabis or cannabinoid...
The British Journal of Psychiatry
May 31, 2011
Maria Alice Fontes, Karen I Bolla, Paulo Jannuzzi Cunha et al.
300 citations
BACKGROUND: Many studies have suggested that adolescence is a period of particular vulnerability to neurocognitive effects associated with substance misuse. However, few large studies have measured differences in cognitive performance between chronic cannabis users who started in early adolescence (before age 15) with those who started later. AIMS: To examine the executive functioning of...
Acta Psychiatrica Scandinavica
May 2011
Chris D Schubart, Marco P Boks, E J Breetvelt et al.
To investigate the relationship between cannabis use and mental health. A cross-sectional analysis in a sample of 17 698 individuals with a mean age of 22 years (SD: 4.2). Participants provided information on the amount and initial age of cannabis use and history of psychiatric hospitalizations through a web-based questionnaire. To quantify Δ(9) -tetrahydrocannabinol exposure, we...
Dusunen Adam: The Journal of Psychiatry and Neurological Sciences
April 21, 2011
Gökhan Umut, İlker Küçükparlak, Güliz Özgen et al.
2 citations
A mood disorder episode with an onset under chronic cannabis consumption and accompanied with psychotic features immediately after N,N-Dimethyltryptamine (DMT) use: case report N,N-dimethyltryptamine (DMT) is a serotonin agonist hallucinogen, similar to lysergic acid diethylamide (LSD).Synthetic production of DMT as well as extraction from several plants of South American flora is possible.DMT...
The International Journal of Neuropsychopharmacology
April 14, 2011
Hendrika H Van Hell, Matthijs G. Bossong, Gerry Jager et al.
61 citations
The main reason for recreational use of cannabis is the 'high', the primary psychotropic effect of Δ9-tetrahydrocannabinol (THC). This psychoactive compound of cannabis induces a range of subjective, physical and mental reactions. The effect on heart rate is pronounced and complicates bloodflow-based neuroimaging of psychotropic effects of THC. In this study we investigated the effects of THC...
European Journal of Pharmacology
April 10, 2011
D Matthew Walentiny, Thomas F Gamage, Jonathan A Warner et al.
The endogenous cannabinoid system has been noted for its therapeutic potential, as well as the psychoactivity of cannabinoids such as Δ9-tetrahydrocannabinol (THC). However, less is known about the psychoactivity of anandamide (AEA), an endocannabinoid ligand. Thus, the goals of this study were to establish AEA as a discriminative stimulus in transgenic mice lacking fatty acid amide hydrolase...
Human psychopharmacology
April 2011
Kerri Alexandra Schoedel, Nancy Chen, Annie Hilliard et al.
This study aimed to evaluate the abuse potential and cognitive effects of nabiximols (Sativex, GW Pharma Ltd. Salisbury, UK), an oromucosal spray primarily containing delta‐9‐tetrahydrocannabinol (THC) and cannabidiol (CBD). This was a single‐dose, randomized, double‐blind, crossover study comparing nabiximols (4, 8, and 16 consecutive sprays: 10.8, 21.6, and 43.2 mg THC, respectively) with...
The Open Addiction Journal
March 29, 2011
Jacqui Rodgers
7 citations
The aim of this investigation was to extend our previous work and establish whether the findings reported previously of self reports of memory difficulties associated with ecstasy use can be replicated. A web-based methodology was adopted due to the significant advantages such techniques may confer when trying to reach a specialized population or address questions that people might be reluctant...
Brain Research
March 25, 2011
Lívia Carla de Melo Rodrigues, Catarine Lima Conti, Ester Miyuki Nakamura-Palacios
Marijuana (Cannabis sativa) is one of the most widely used illicit drugs in the world. Its use is associated with impairments in cognitive function. We previously reported that Δ(9)-tetrahydrocannabinol (Δ(9)-THC), the primary psychoactive component of marijuana, impaired spatial working memory in the radial maze task when injected intracortically (IC) into the medial prefrontal cortex (mPFC)...
Schizophrenia Bulletin
March 9, 2011
Verity C. Leeson, Isobel Harrison, María A. Ron et al.
132 citations
OBJECTIVE: Cannabis use is associated with a younger age at onset of psychosis, an indicator of poor prognosis, but better cognitive function, a positive prognostic indicator. We aimed to clarify the role of age at onset and cognition on outcomes in cannabis users with first-episode schizophrenia as well as the effect of cannabis dose and cessation of use. METHODS: Ninety-nine patients without...
Pharmacology, Biochemistry, and Behavior
March 2011
Dawn E Sugarman, James Poling, Mehmet Sofuoglu
Marijuana (cannabis) is the most widely used illicit substance globally, and cannabis use is associated with a range of adverse consequences. Currently, no medications have been proven to be effective for the treatment of cannabis addiction. The goals of this study were to examine the safety and efficacy of a potential treatment medication, modafinil, in combination with oral...