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...
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),...