Australian & New Zealand Journal of Psychiatry
December 1, 2009
Bart D. Peters, Pelle de Koning, Peter M. A. J. Dingemans et al.
35 citations
OBJECTIVE: The aim of the present study was to gain more insight into the positive and negative effects of cannabis in the prodromal phase of schizophrenia and in the ultra-high-risk (UHR) state for psychosis. METHOD: A theory-driven questionnaire was used to examine subjective effects in the prodromal phase in male subjects with a recent onset of schizophrenia or related disorder (n = 52) and...
International Journal of Culture and Mental Health
December 1, 2009
Fabrizio Schifano, Ornella Corazza, Paolo Deluca et al.
79 citations
The aim of the study was to foster the collection and analysis of data from web pages related to information on the consumption, manufacture and sale of Spice products, a brand name for an herbal smoking blend, sold as legal substitute for cannabis. The Google search engine was used to carry out an 8-language qualitative assessment of information available on Spice products in a sample of about...
Journal of Psychoactive Drugs
December 1, 2009
Katy A. Jones, Mark Blagrove, A. C. Parrott
41 citations
This study investigated the associations between chronic cannabis and Ecstasy/MDMA use and one objective and two subjective measure of creativity. Fifteen abstinent Ecstasy users, 15 abstinent cannabis users, and 15 nondrug-user controls, completed three measures of creativity: the Consequences behavioral test of creativity, self-assessed performance on the Consequences test, and Gough's Trait...
The British Journal of Psychiatry
November 30, 2009
Marta Di Forti, Craig Morgan, Paola Dazzan et al.
577 citations
BACKGROUND: People who use cannabis have an increased risk of psychosis, an effect attributed to the active ingredient Delta 9-tetrahydrocannabinol (Delta 9-THC). There has recently been concern over an increase in the concentration of Delta 9-THC in the cannabis available in many countries. AIMS: To investigate whether people with a first episode of psychosis were particularly likely to use...
Journal of Psychopharmacology
November 25, 2009
Celia J. A. Morgan, Leslie Muetzelfeldt, Mark Muetzelfeldt et al.
80 citations
Nutt and colleagues' 'rational' scale to assess the harms of commonly used drugs was based on ratings by a panel of experts. This survey aimed to assess drug users' views of the harms of drugs using the same scale. As users' drug choices are not solely based on harms, we additionally assessed perceived benefits. The survey was hosted at http://www.nationaldrugsurvey.org. UK residents reported...
Neuropsychopharmacology
November 18, 2009
Opposite effects of delta-9-tetrahydrocannabinol and cannabidiol on human brain function and psychopathology.
Schizophrenia Bulletin
November 13, 2009
Ana González-Pinto, Susana Alberich, Sara Barbeito et al.
Objective: To examine the influence of cannabis use on long-term outcome in patients with a first psychotic episode, comparing patients who have never used cannabis with (a) those who used cannabis before the first episode but stopped using it during follow-up and (b) those who used cannabis both before the first episode and during follow-up. Methods: Patients were studied following their first...
Drug and Alcohol Dependence
November 1, 2009
Staci A Gruber, Jadwiga Rogowska, Deborah A Yurgelun-Todd
More than 94 million Americans have tried marijuana, and it remains the most widely used illicit drug in the nation. Investigations of the cognitive effects of marijuana report alterations in brain function during tasks requiring executive control, including inhibition and decision-making. Endogenous cannabinoids regulate a variety of emotional responses, including anxiety, mood control, and...
British Journal of Pharmacology
November 2009
Nathan Gunasekaran, L E Long, B L Dawson et al.
Delta(9)-tetrahydrocannabinol (THC), the main psychoactive constituent of cannabis, accumulates in adipose tissue where it is stored for long periods of time. Here we investigated whether conditions that promote lipolysis can liberate THC from adipocytes to yield increased blood levels of THC. In vitro studies involved freshly isolated rat adipocytes that were incubated with THC before exposure...
October 30, 2009
O. Oshodi, O. Ikeji, S. Olotu et al.
Hospital records of patients seen between 1999 and 2002 were carefully examined. A questionnaire was used to extract relevant information from the case records and clinical diagnosis was made using the ICD-10. Cases that had evidence of pre-existing psychiatric disorder, family history of mental illness or heavy use of alcohol and/or tobacco were excluded. Out of 6,556 patients that were seen...
Psychological Medicine
October 2009
Paul D. Morrison, V Zois, D A McKeown et al.
Recent work suggests that heavy use of cannabis is associated with an increased risk of schizophrenia-like psychosis. However, there is a dearth of experimental studies of the effects of the constituents of cannabis, such as Delta9-tetrahydrocannabinol (THC). In a study of intravenous (i.v.) synthetic THC in healthy humans, we aimed to study the relationship of the psychotic symptoms induced by...
American Journal of Psychiatry
October 1, 2009
Michael T Compton, M. Kelley, Claire E. Ramsay et al.
Objective Several reports suggest that cannabis use is associated with an earlier age at onset of psychosis, though not all studies have operationalized cannabis use as occurring prior to onset of symptoms. This study addressed whether pre-onset cannabis use (and alcohol and tobacco use) is associated with an earlier age at onset of prodromal and psychotic symptoms. Additionally, effects of the...
Neuropsychopharmacology
October 2009
Lydie J Morel, Bruno Giros, Valérie Daugé
Maternal deprivation in rats specifically leads to a vulnerability to opiate dependence. However, the impact of cannabis exposure during adolescence on this opiate vulnerability has not been investigated. Chronic dronabinol (natural delta-9 tetrahydrocannabinol, THC) exposure during postnatal days 35-49 was made in maternal deprived (D) or non-deprived (animal facility rearing, AFR) rats. The...
PLoS Medicine
September 28, 2009
Louisa Degenhardt, Wayne Hall, Michael T. Lynskey et al.
48 citations
N Comparative risk assessments estimate the proportion of a disease that can be attributed to a particular risk exposure and are important guides for health planning.N In observational studies, there has been consistent evidence that cannabis use is associated with an increased risk of schizophrenia and more generally, psychosis.N There is debate about whether such observational evidence is...
The International Journal of Neuropsychopharmacology
September 24, 2009
Paolo Fusar‐poli, Paul Allen, Sagnik Bhattacharyya et al.
165 citations
Cannabis sativa, the most widely used illicit drug, has profound effects on levels of anxiety in animals and humans. Although recent studies have helped provide a better understanding of the neurofunctional correlates of these effects, indicating the involvement of the amygdala and cingulate cortex, their reciprocal influence is still mostly unknown. In this study dynamic causal modelling (DCM)...
Adicciones
September 1, 2009
Cristina Mustata, Marta Torrens, Ricardo Pardo et al.
33 citations
Desde 2004 se venden en Internet y tiendas especializadas (smart shops) algunos preparados conteniendo mezclas de hierbas para fumar con la marca de Spice drugs. Estos productos se publicitan como una mezcla exótica de incienso aromático y se especifica que no son aptos para uso humano. Muchos usuarios, tras consumir estos productos fumados, refieren que sus efectos son similares a los del...
Journal of Psychoactive Drugs
September 1, 2009
Dawn N Albertson, Laura E Grubbs
29 citations
Salvia divinorum is a naturally occurring psychedelic considered to be one of the most potent hallucinogens found to date. The few behavioral studies conducted conclude that Salvia's effects may be similar to traditional psychedelics, which is noteworthy because Salvia acts via a unique molecular mechanism as a kappa opioid receptor agonist. One hundred and ninety-three participants, including...
Pharmacology, Biochemistry, and Behavior
August 2009
Daniel Thomas Malone, Dennis Jongejan, David Alan Taylor
While Delta(9)-tetrahydrocannabinol (THC) is the main psychoactive constituent of the cannabis plant, a non-psychoactive constituent is cannabidiol (CBD). CBD has been implicated as a potential treatment of a number of disorders including schizophrenia and epilepsy and has been included with THC in a 1:1 combination for the treatment of conditions such as neuropathic pain. This study...
Experimental and Clinical Psychopharmacology
August 1, 2009
Jane Metrik, Damaris J Rohsenow, Peter M. Monti et al.
Although alcohol and nicotine administration studies have demonstrated that manipulating subjects' expectancies regarding drug content affects drug response, research with marijuana has not adequately studied drug expectancy effects. The present pilot study was the first to evaluate the credibility and effect of expectancy manipulation on subjective measures and smoking patterns using a...
European Archives of Psychiatry and Clinical Neuroscience
August 2009
Patrik Roser, Jürgen Gallinat, Gordon Weinberg et al.
Abnormalities in psychomotor performance are a consistent finding in schizophrenic patients as well as in chronic cannabis users. The high levels of central cannabinoid (CB(1)) receptors in the basal ganglia, the cerebral cortex and the cerebellum indicate their implication in the regulation of motor activity. Based on the close relationship between cannabis use, the endogenous cannabinoid...