PLoS One
December 18, 2012
Stanley C. Flavel, Jenna D. Koch, Jason M. White et al.
30 citations
Use of illicit stimulants such as methamphetamine, cocaine, and ecstasy is a significant health problem. The United Nations Office on Drugs and Crime estimates that 14-57 million people use stimulants each year. Chronic use of illicit stimulants can cause neurotoxicity in animals and humans but the long-term functional consequences are not well understood. Stimulant users self-report problems...
Addiction
December 10, 2012
Merel F. H. Griffith‐Lendering, Johanna T. W. Wigman, Andrea Prince van Leeuwen et al.
67 citations
AIMS: To examine the direction of the longitudinal association between vulnerability for psychosis and cannabis use throughout adolescence. DESIGN: Cross-lagged path analysis was used to identify the temporal order of vulnerability for psychosis and cannabis use, while controlling for gender, family psychopathology, alcohol use and tobacco use. SETTING: A large prospective population study of...
Psychological Medicine
December 1, 2012
Andrea M. Auther, Danielle McLaughlin, Ricardo E Carrión et al.
Background: Clinical and epidemiological studies suggest an association between cannabis use and psychosis but this relationship remains controversial. Method: Clinical high-risk (CHR) subjects (age 12–22 years) with attenuated positive symptoms of psychosis (CHR+,n=101) were compared to healthy controls (HC,n=59) on rates of substance use, including cannabis. CHR+ subjects with and without...
Drug and Alcohol Dependence
December 1, 2012
Jason M Wiebelhaus, Justin L. Poklis, Alphonse Poklis et al.
Use of synthetic "marijuana" has increased in recent years, produced adverse effects and prompted the temporary DEA ban of five specific cannabinoid analogs, including JWH-018. The objectives of the current study include determining the chemical content of the herbal product, Buzz, assessing its behavioral effects upon inhalation exposure to mice, determining whether CB(1) receptors mediate its...
Psychopharmacology
November 24, 2012
Richard A Sewell, Ashley Schnakenberg, Jacqueline Elander et al.
Cannabinoids have been shown to alter time perception, but existing literature has several limitations. Few studies have included both time estimation and production tasks, few control for subvocal counting, most had small sample sizes, some did not record subjects’ cannabis use, many tested only one dose, and used either oral or inhaled administration of Δ9-tetrahydrocannabinol (THC), leading...
Neuroimage
November 15, 2012
Linda E. Klumpers, David M. Cole, Najmeh Khalili-Mahani et al.
Resting state-functional magnetic resonance imaging (RS-FMRI) is a neuroimaging technique that allows repeated assessments of functional connectivity in resting state. While task-related FMRI is limited to indirectly measured drug effects in areas affected by the task, resting state can show direct CNS effects across all brain networks. Hence, RS-FMRI could be an objective measure for compounds...
Biological Psychiatry
November 15, 2012
Hilarie C Tomasiewicz, Michelle M Jacobs, Matthew B Wilkinson et al.
Marijuana use by teenagers often predates the use of harder drugs, but the neurobiological underpinnings of such vulnerability are unknown. Animal studies suggest enhanced heroin self-administration (SA) and dysregulation of the endogenous opioid system in the nucleus accumbens shell (NAcsh) of adults following adolescent Δ(9)-tetrahydrocannabinol (THC) exposure. However, a causal link between...
Drug and Alcohol Dependence
November 1, 2012
Joshua A Lile, Thomas H Kelly, Lon R Hays
Our previous research with the GABA reuptake inhibitor tiagabine suggested the involvement GABA in the interoceptive effects of Δ9-THC. The aim of the present study was to determine the potential involvement of the GABA(B) receptor subtype by assessing the separate and combined effects of the GABA(B)-selective agonist baclofen and Δ9-THC using pharmacologically specific drug-discrimination...
American Journal on Addictions
November 1, 2012
Alexander Baldacchino, Zoe Hughes, Michael Kehoe et al.
The term "cannabis psychosis" has become ubiquitous in the psychiatric literature. Few authors have described the precise psychopathology of this potentially distinct subtype of psychosis. Specifically, little attention has been paid to exploring whether cannabis psychosis is characterized by a psychopathology which is different from that of other types of psychosis. The purpose of this paper...
Journal of Psychoactive Drugs
November 1, 2012
Michael Lyvers, Molly Meester
97 citations
Psychedelic drugs have long been known to be capable of inducing mystical or transcendental experiences. However, given the common "recreational" nature of much present-day psychedelic use, with typical doses tending to be lower than those commonly taken in the 1960s, the extent to which illicit use of psychedelics today is associated with mystical experiences is not known. Furthermore the mild...
Journal of Psychopharmacology
October 5, 2012
Amir Englund, Paul D. Morrison, Judith Nottage et al.
463 citations
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...
Neuroscience Letters
October 3, 2012
Nicholas A Swartzwelder, M Louise Risher, Sabri H Abdelwahab et al.
Recent advances have been made in our understanding of the deleterious effects of both ethanol and THC on adolescent behavior and brain development. However, very little is known about the combined effects of EtOH+THC during adolescence, a time in which these drugs are often used together. The purpose of this experiment was to: (1) determine whether EtOH and/or THC induced greater working...
The International Journal of Neuropsychopharmacology
October 2012
Mohini Ranganathan, Michelle Carbuto, Gabriel Braley et al.
Although a wealth of preclinical evidence indicates an interplay between the μ-opioid (MOR) and cannabinoid 1 receptor (CB1R) systems, the precise nature of the cross modulation in humans is unclear. The objective of this study was to evaluate the effects of pretreatment with the MOR antagonist, naltrexone, on the subjective, behavioural and cognitive effects of the CB1R agonist,...
Journal of Psychopharmacology
October 2012
Michael A. Taffe
Cannabis remains the most commonly abused illicit drug and is rapidly expanding in quasi-licit use in some jurisdictions under medical marijuana laws. Effects of the psychoactive constituent Δ⁹tetrahydrocannabinol (Δ⁹THC) on cognitive function remain of pressing concern. Prior studies in monkeys have not shown consistent evidence of memory-specific effects of Δ⁹THC on recognition tasks, and it...
Psychopharmacology
October 2012
Jane Metrik, Christopher W Kahler, Brady Reynolds et al.
Marijuana is believed to increase impulsivity and risk taking, but the processes whereby it affects such behaviors are not understood. Indeed, either the pharmacologic effect of delta-9-tetrahydrocannabinol (THC) or the expectancy of receiving it may lead to deficits in cognitive processing and increases in risk taking. We examined the relative effects of expecting to receive active marijuana...
Psychological Medicine
October 1, 2012
Zerrin Atakan, Sagnik Bhattacharyya, Paul Allen et al.
54 citations
BACKGROUND: Cannabis can induce transient psychotic symptoms, but not all users experience these adverse effects. We compared the neural response to Δ9-tetrahydrocannabinol (THC) in healthy volunteers in whom the drug did or did not induce acute psychotic symptoms. Method In a double-blind, placebo-controlled, pseudorandomized design, 21 healthy men with minimal experience of cannabis were...
Current Pharmaceutical Design
September 12, 2012
Anna Buadze, Stefan Kaiser, Rudolf Stohler et al.
10 citations
Over the past years a growing research effort has investigated the relation between cannabis use and schizophrenia at a neurobiological, epidemiological and clinical level. A number of systematic reviews and meta analyses have summarized the available evidence in the field. Conversely the patient's perception of the link between cannabis use and psychosis has been under investigation. Since...
Current Pharmaceutical Design
September 12, 2012
Rocío Martín‐Santos, José Alexandre S. Crippa, Albert Batalla et al.
288 citations
RATIONALE: Animal and humans studies suggest that the two main constituents of cannabis sativa, delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) have quite different acute effects. However, to date the two compounds have largely been studied separately. OBJECTIVE: To evaluate and compare the acute pharmacological effects of both THC and CBD in the same human volunteers. METHODS: A...
Experimental Brain Research
September 2012
Miriam Fishbein, Sahar Gov, Fadi Assaf et al.
We have previously reported that a single injection of an ultra-low dose of delta-9-tetrahydrocannabinol (THC; the psychoactive ingredient of marijuana) protected the brain from pentylenentetrazole (PTZ)-induced cognitive deficits when applied 1-7 days before or 1-3 days after the insult. In the present study we expanded the protective profile of THC by showing that it protected mice from...
Pharmacology, Biochemistry, and Behavior
September 2012
Peter J Winsauer, Catalin M Filipeanu, Evangeline M Bailey et al.
Marijuana abuse during adolescence may alter its abuse liability during adulthood by modifying the interoceptive (discriminative) stimuli produced, especially in females due to an interaction with ovarian hormones. To examine this possibility, either gonadally intact or ovariectomized (OVX) female rats received 40 intraperitoneal injections of saline or 5.6 mg/kg of Δ⁹-THC daily during...