Translational Psychiatry
September 5, 2018
Celia J. A. Morgan, Tom P. Freeman, Chandni Hindocha et al.
The main active ingredient in cannabis, delta-9-tetrahydrocannabinol (THC), can acutely induce psychotic symptoms and impair episodic and working memory. Another major constituent, cannabidiol (CBD), may attenuate these effects. This study aimed to determine the effects of THC and CBD, both alone and in combination on psychotic symptoms and memory function. A randomised, double-blind crossover...
European Neuropsychopharmacology
March 2015
Chandni Hindocha, Tom P. Freeman, Gráinne Schäfer et al.
Acute administration of the primary psychoactive constituent of cannabis, Δ-9-tetrahydrocannabinol (THC), impairs human facial affect recognition, implicating the endocannabinoid system in emotional processing. Another main constituent of cannabis, cannabidiol (CBD), has seemingly opposite functional effects on the brain. This study aimed to determine the effects of THC and CBD, both alone and...
Addiction
October 2014
Tom P. Freeman, Celia J. A. Morgan, Chandni Hindocha et al.
(1) To determine whether measured concentrations of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) in individuals' own cannabis predict their estimates of drug potency and actual titration; and (2) to ascertain if these effects are influenced by frequency of use and cannabis type. Cross-sectional, naturalistic. Participants' own homes. A total of 247 cannabis users in the United...
Consciousness and Cognition
January 10, 2012
Gráinne Schäfer, Amanda Feilding, Celia J. A. Morgan et al.
60 citations
Cannabis acutely increases schizotypy and chronic use is associated with elevated rates of psychosis. Creative individuals have higher levels of schizotypy, however links between cannabis use, schizotypy and creativity have not been investigated. We investigated the effects of cannabis smoked naturalistically on schizotypy and divergent thinking, a measure of creativity. One hundred and sixty...
The British Journal of Psychiatry
October 2010
Celia J. A. Morgan, Gráinne Schäfer, Tom P. Freeman et al.
The two main constituents of cannabis, cannabidiol and Δ(9)-tetrahydrocannabinol (THC), have opposing effects both pharmacologically and behaviourally when administered in the laboratory. Street cannabis is known to contain varying levels of each cannabinoid. To study how the varying levels of cannabidiol and THC have an impact on the acute effects of the drug in naturalistic settings. Cannabis...
Neuropsychopharmacology
August 2010
Celia J A Morgan, Tom P. Freeman, Gráinne Schäfer et al.
Worldwide cannabis dependence is increasing, as is the concentration of Delta(9)-tetrahydrocannabinol (THC) in street cannabis. At the same time, the concentration of the second most abundant cannabinoid in street cannabis, cannabidiol (CBD), is decreasing. These two cannabinoids have opposing effects both pharmacologically and behaviorally when administered in the laboratory. No research has...