European Psychiatry
March 1, 2011
B. Schimmelmann, S. Kupferschmid, Philippe Conus et al.
Background: Age at onset of psychosis (AAO) may be younger in patients with cannabis use disorders (CUD) compared to those without CUD (NCUD). Most previous studies did not control for potential confounders, did not report effect sizes and included mostly adult patients from non-representative samples. Methods: Controlling for relevant confounders, differences in AAO between patients with and...
Journal of Addiction Medicine
March 2011
Rebecca D Crean, Susan F Tapert, Arpi Minassian et al.
This case describes the clinical course of a cannabis-dependent individual entering a 12-week abstinence-based research program. The case illustrates the effects of chronic, heavy cannabis use on executive functions at three time points: 1) 24 hours of abstinence; 2) 4 weeks of abstinence; and 3) 12 weeks of abstinence. It is followed by discussions by two clinical psychologists and a...
Journal of Addiction Medicine
March 2011
Rebecca D Crean, Natania A. Crane, Barbara J Mason
Cannabis use has been shown to impair cognitive functions on a number of levels-from basic motor coordination to more complex executive function tasks, such as the ability to plan, organize, solve problems, make decisions, remember, and control emotions and behavior. These deficits differ in severity depending on the quantity, recency, age of onset and duration of marijuana use. Understanding...
BMJ
March 1, 2011
Rebecca Kuepper, Jim van Os, Roselind Lieb et al.
307 citations
OBJECTIVE: To determine whether use of cannabis in adolescence increases the risk for psychotic outcomes by affecting the incidence and persistence of subclinical expression of psychosis in the general population (that is, expression of psychosis below the level required for a clinical diagnosis). DESIGN: Analysis of data from a prospective population based cohort study in Germany (early...
Clinical Pharmacology & Therapeutics
March 2011
E L Karschner, William D Darwin, Robert P McMahon et al.
Sativex is a cannabis-plant extract delivering nearly 1:1 Δ(9)-tetrahydrocannabinol (THC) and cannabidiol (CBD) by oromucosal spray. It has been suggested that CBD attenuates THC-induced tachycardia, anxiety, and euphoria. In this study, pharmacodynamic effects were compared over 10.5 h in nine cannabis smokers randomly assigned to receive placebo, 5 and 15 mg oral synthetic THC, and low (5.4...
Journal of Psychiatric Research
February 5, 2011
M. Ashtari, B. Avants, L. Cyckowski et al.
Converging lines of evidence suggest an adverse effect of heavy cannabis use on adolescent brain development, particularly on the hippocampus. In this preliminary study, we compared hippocampal morphology in 14 “treatment-seeking” adolescents (aged 18-20) with a history of prior heavy-cannabis use (5.8 joints/day) after an average of 6.7 months of drug abstinence, and 14 demographically matched...
Archives of General Psychiatry
February 2011
Individual differences in cannabis sensitivity may be associated with genetic risk for psychotic disorder. To demonstrate and replicate, using 2 conceptually different genetic epidemiological designs, that (familial) liability to psychosis is associated with sensitivity to cannabis. Sibling-control and cross-sibling comparisons using samples of patients with a psychotic disorder (n = 1120),...
Archives of General Psychiatry
February 2011
Ruud van Winkel
Individual differences exist in sensitivity to the psychotomimetic effect of cannabis; the molecular genetic basis underlying differential sensitivity remains elusive. To investigate whether selected schizophrenia candidate single-nucleotide polymorphisms (SNPs) moderate effects of cannabis use. Interactions between recent cannabis use, determined by urinalysis results, and 152 SNPs in 42...
Psychopharmacology
February 2011
Marieke M Lansbergen, Glenn Dumont, Joop van Gerven et al.
Typical users of 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy") are polydrug users, combining MDMA with alcohol or cannabis [most active compound: delta-9-tetrahydrocannabinol (THC)]. The aim of the present study was to investigate whether co-administration of alcohol or THC with MDMA differentially affects ongoing electroencephalogram (EEG) oscillations compared to the administration of...
Neuropharmacology
2011
Natalia Realini, Daniela Vigano', Cinzia Guidali et al.
We have recently shown that chronic THC administration in adolescent female rats induces subtle but lasting alterations in the emotional circuit ending in depressive-like behaviour at adulthood. Here we describe other relevant depressive-like symptoms present in these animals. Adult female rats pretreated with THC display passive coping strategy towards acute stressful situations as...
Human psychopharmacology
January 2011
Paul D. Morrison, J M Stone
It is unknown if cannabis recreates the negative symptoms of schizophrenia. Healthy male volunteers (n = 22) completed two experimental sessions in which they received intravenous (IV) delta-9-tetrahydrocannabinol (THC) 2.5 mg or placebo in a randomised counterbalanced order. Negative symptoms were rated using the self-reported community assessment of psychic experiences scale (CAPE). Sedation...
Addiction Biology
January 2011
Peter J Winsauer, Jill M Daniel, Catalin M Filipeanu et al.
Abuse of Δ⁹-THC by females during adolescence may produce long-term deficits in complex behavioral processes such as learning, and these deficits may be affected by the presence of ovarian hormones. To assess this possibility, 40 injections of saline or 5.6 mg/kg of Δ⁹-THC were administered i.p. daily during adolescence to gonadally intact or ovariectomized (OVX) female rats, yielding four...
ILAR Journal
2011
Divya Ramesh, Joel E Schlosburg, Jason M Wiebelhaus et al.
Marijuana (Cannabis sativa) is the most commonly used illicit drug worldwide as well as in the Unites States. Prolonged use of marijuana or repeated administration of its primary psychoactive constituent, Δ9-tetrahydrocannabinol (THC), can lead to physical dependence in humans and laboratory animals. The changes that occur with repeated cannabis use include alterations in behavioral,...
Indian Journal of Psychiatry
January 2011
Shubhangi R Parkar, Seethalakshmi Ramanathan, Narendra Nair et al.
Cannabis has been associated with transient psychotic states; however, the causal relationship between cannabis and schizophrenia continues to remain a matter of debate. Epidemiological and some biological studies hint at cannabis being an independent risk factor for schizophrenia; this has not been definitively proved. We aimed to understand the patterns of glucose uptake in important brain...
Brain Connectivity
2011
Dae-Jin Kim, Patrick D. Skosnik, Hu Cheng et al.
Endocannabinoid receptors modulate synaptic plasticity in the brain and may therefore impact cortical connectivity not only during development but also in response to substance abuse in later life. Such alterations may not be evident in volumetric measures utilized in brain imaging, but could affect the local and global organization of brain networks. To test this hypothesis, we used a novel...
Neuropsychopharmacologia Hungarica
2011
Zoltán Makkos, Lilla Fejes, Gabriella Inczédy-Farkas et al.
3 citations
Marijuana (cannabis) is the most commonly abused drug by adolescents and young adults and also by people with schizophrenia or other psychotic disorders. An increasing number of studies suggest that regular cannabis users can show psychotic episodes similar to schizophrenic disorders but it still unclear if cannabis induced psychotic disorder is a distinct entity requiring special therapy or...
Indian Journal of Psychiatry
2011
Amresh Shrivastava, Megan Johnston, Ming T. Tsuang
69 citations
This review considers the effects of cannabis on cognitive functioning, in both short and long term. Although the general impression supported by many studies is that cannabis causes cognitive decline, particularly with long-term usage, some research suggests that this may not be the case. Nevertheless, certain specific neuropsychological parameters have been found to be affected. Most commonly...
2011
M. Konings
Chapter IVValidity and reliability of the CAPE: a self-report instrument for the measurement of psychotic experiences in the general population 51 Chapter V Early exposure to cannabis and risk for psychosis in young adolescents in Trinidad 61Chapter VI Evidence from two prospective population-based studies for interaction between cannabis use and childhood trauma on psychosis risk.
Frontiers in Behavioral Neuroscience
2011
Liana Fattore, Walter Fratta
443 citations
Synthetic cannabinoids are functionally similar to delta9-tetrahydrocannabinol (THC), the psychoactive principle of cannabis, and bind to the same cannabinoid receptors in the brain and peripheral organs. From 2008, synthetic cannabinoids were detected in herbal smoking mixtures sold on websites and in "head shops" under the brand name of Spice Gold, Yucatan Fire, Aroma, and others. Although...
Farmacognosia
2011
F. Capasso
Gli allucinogeni sono sostanze psicoattive capaci di causare ‘sostanziali e transitorie modificazioni della percezione, del pensiero e dell’umore’. Possono essere classificate in base al loro meccanismo d‘azione oppure in base alla loro struttura chimica.