bioRxiv (Cold Spring Harbor Laboratory)
June 5, 2025
Ekaterina Shatalina, Natalie Ertl, Kat Petrilli et al.
1 citation
preprint
Abstract Background Cannabis is one of the most widely used psychoactive substances in the world and is increasingly investigated as a treatment for neuropsychiatric conditions. Cannabis contains delta-9-tetrahydrocannabinol (THC), which is thought to underlie its main psychoactive effects, and cannabidiol (CBD), which has been proposed to modulate the effects of THC on the brain. Both have...
The International Journal of Neuropsychopharmacology
February 1, 2025
Martine Skumlien, Tom P. Freeman, Daniel L. Hall et al.
Abstract Background Cannabis, and its main psychoactive compound tetrahydrocannabinol (THC), may alter the brain’ s reward system both acutely and over time. The endocannabinoid and reward systems mature during adolescence and adolescents may therefore respond differently to acute cannabis exposure compared with adults. Despite this, no previous functional magnetic resonance imaging (fMRI)...
Neuropsychopharmacology
May 28, 2024
Natalie Ertl, Tom P. Freeman, Claire Mokrysz et al.
19 citations
Adolescence is a time of rapid neurodevelopment and the endocannabinoid system is particularly prone to change during this time. Cannabis is a commonly used drug with a particularly high prevalence of use among adolescents. The two predominant phytocannabinoids are Delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), which affect the endocannabinoid system. It is unknown whether this...
Psychopharmacology
February 28, 2024
Daniel L. Hall, Will Lawn, Shelan Ofori et al.
5 citations
RATIONALE: Attentional bias to drug-related stimuli is hypothesised to contribute towards addiction. However, the acute effects of Δ9-tetrahydrocannabinol (THC) on attentional bias to cannabis cues, the differential response in adults and adolescents, and the moderating effect of cannabidiol (CBD) are unknown. OBJECTIVES: Our study investigated (1) the acute effects of vaporised cannabis on...
Journal of Psychopharmacology
July 29, 2023
Natalie Ertl, Will Lawn, Claire Mokrysz et al.
17 citations
BACKGROUND/AIM: Cannabis use is highly prevalent in adolescents; however, little is known about its effects on adolescent brain function. METHOD: = 70, 35 adolescents/35 adults). Pre-registered analyses examined the connectivity of seven major cortical and sub-cortical brain networks (default mode network, executive control network (ECN), salience network, hippocampal network and three striatal...
Addiction
February 8, 2023
Will Lawn, Katie Trinci, Claire Mokrysz et al.
36 citations
Abstract Background and Aims Long‐term harms of cannabis may be exacerbated in adolescence, but little is known about the acute effects of cannabis in adolescents. We aimed to (i) compare the acute effects of cannabis in adolescent and adult cannabis users and (ii) determine if cannabidiol (CBD) acutely modulates the effects of delta‐9‐tetrahydocannabinol (THC). Design Randomised, double‐blind,...
Journal of Psychopharmacology
May 20, 2022
Matthew B. Wall, Tom P. Freeman, Chandni Hindocha et al.
21 citations
Background: Cannabidiol (CBD) and Δ 9 -tetrahydrocannabinol (THC) are the two major constituents of cannabis with contrasting mechanisms of action. THC is the major psychoactive, addiction-promoting, and psychotomimetic compound, while CBD may have opposite effects. The brain effects of these drugs alone and in combination are poorly understood. In particular, the striatum is implicated in the...
American Journal of Psychiatry
January 11, 2022
Meryem Grabski, Amy Mcandrew, Will Lawn et al.
169 citations
OBJECTIVE: Early evidence suggests that ketamine may be an effective treatment to sustain abstinence from alcohol. The authors investigated the safety and efficacy of ketamine compared with placebo in increasing abstinence in patients with alcohol use disorder. An additional aim was to pilot ketamine combined with mindfulness-based relapse prevention therapy compared with ketamine and alcohol...
Journal of Psychopharmacology
January 9, 2021
Abigail M. Freeman, Claire Mokrysz, Chandni Hindocha et al.
6 citations
BACKGROUND: While the acute effects of cannabis are relatively benign for most users, some individuals experience significant adverse effects. This study aimed to identify whether variation in schizotypal personality traits and frequency of cannabis use influence the acute effects of delta-9-tetrahydrocannabinol (THC). METHODS: Individual participant data from four double-blind, randomised,...
bioRxiv (Cold Spring Harbor Laboratory)
November 21, 2020
Matthew B. Wall, Tom P. Freeman, Chandni Hindocha et al.
4 citations
preprint
Abstract Cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) are two major constituents of cannabis with contrasting mechanisms of action. THC is the major psychoactive, addiction-promoting, and psychotomimetic compound, while CBD may have somewhat opposite effects. The brain effects of these drugs alone and in combination are poorly understood. In particular the striatum is implicated in the...
Journal of Psychopharmacology
August 5, 2020
Will Lawn, J. P. Hill, Chandni Hindocha et al.
23 citations
BACKGROUND: Cannabidiol has potential therapeutic benefits for people with psychiatric disorders characterised by reward function impairment. There is existing evidence that cannabidiol may influence some aspects of reward processing. However, it is unknown whether cannabidiol acutely affects brain function underpinning reward anticipation and feedback. HYPOTHESES: We predicted that cannabidiol...
Translational Psychiatry
May 12, 2020
Chandni Hindocha, Diego Quattrone, Tom P. Freeman et al.
Epidemiological and biological evidence support the association between heavy cannabis use and psychosis. However, it is unclear which cannabis users are susceptible to its psychotogenic effect. Therefore, understanding genetic factors contributing to this relationship might prove an important strategy to identify the mechanisms underlying cannabis-associated psychotic experiences. We aimed to...
Psychological Medicine
April 28, 2020
Claire Mokrysz, Natacha D. C. Shaban, Tom P. Freeman et al.
24 citations
BACKGROUND: Acute cannabis administration can produce transient psychotic-like effects in healthy individuals. However, the mechanisms through which this occurs and which factors predict vulnerability remain unclear. We investigate whether cannabis inhalation leads to psychotic-like symptoms and speech illusion; and whether cannabidiol (CBD) blunts such effects (study 1) and adolescence...
UNC Libraries
April 22, 2020
Peter J. Hellyer, Luke T. J. Williams, Ben Sessa et al.
1 citation
Lysergic acid diethylamide (LSD), the prototypical “psychedelic,” may be unique among psychoactive substances. In the decades that followed its discovery, the magnitude of its effect on science, the arts, and society was unprecedented. LSD produces profound, sometimes life-changing experiences in microgram doses, making it a particularly powerful scientific tool. Here we sought to examine its...
Journal of Psychopharmacology
April 23, 2019
Matthew B. Wall, Rebecca Pope, Tom P. Freeman et al.
89 citations
BACKGROUND: -tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is the main psychoactive component; CBD may buffer the user against the harmful effects of THC. AIMS: We examined the effects of two strains of cannabis and placebo on the human brain's resting-state networks using fMRI. METHODS: Seventeen healthy volunteers (experienced with cannabis, but not regular users) underwent three drug...
Journal of Psychopharmacology
February 21, 2019
Hina Akram, Claire Mokrysz, H. Valerie Curran
57 citations
BACKGROUND: Synthetic cannabinoids are, typically, full agonists at the cannabinoid CB1 receptor, and therefore considerably more potent than natural cannabis and may have correspondingly more serious psychological effects. Despite government sanctions against their production they continue to be available in ever-increasing varieties over the Internet. The psychological consequences of...
Psychopharmacology (Berl)
February 1, 2018
H. Valerie Curran, David Nutt, Harriet de Wit
17 citations
Psychedelics and related drugs: therapeutic possibilities, mechanisms and regulation.
The International Journal of Neuropsychopharmacology
August 30, 2017
Tom P. Freeman, Rebecca Pope, Matthew B. Wall et al.
67 citations
Background: Despite the current shift towards permissive cannabis policies, few studies have investigated the pleasurable effects users seek. Here, we investigate the effects of cannabis on listening to music, a rewarding activity that frequently occurs in the context of recreational cannabis use. We additionally tested how these effects are influenced by cannabidiol, which may offset...
Psychopharmacology
September 2, 2016
Will Lawn, Tom P. Freeman, Rebecca Pope et al.
177 citations
RATIONALE: Anecdotally, both acute and chronic cannabis use have been associated with apathy, amotivation, and other reward processing deficits. To date, empirical support for these effects is limited, and no previous studies have assessed both acute effects of Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), as well as associations with cannabis dependence. OBJECTIVES: The objectives of...
Proc Natl Acad Sci U S A
April 11, 2016
Robin Carhart-Harris, Suresh Muthukumaraswamy, Leor Roseman et al.
887 citations
Lysergic acid diethylamide (LSD) is the prototypical psychedelic drug, but its effects on the human brain have never been studied before with modern neuroimaging. Here, three complementary neuroimaging techniques: arterial spin labeling (ASL), blood oxygen level-dependent (BOLD) measures, and magnetoencephalography (MEG), implemented during resting state conditions, revealed marked changes in...
Journal of Psychopharmacology
May 18, 2015
Sunjeev K. Kamboj, Emma J. Kilford, Stephanie Minchin et al.
43 citations
3,4-methylenedioxy- N-methylamphetamine (MDMA) produces diverse pro-social effects. Cognitive training methods rooted in Eastern contemplative practices also produce these effects through the development of a compassionate mindset. Given this similarity, we propose that one potential mechanism of action of MDMA in psychotherapy is through enhancing effects on intrapersonal attitudes (i.e....
Journal of Psychopharmacology
August 13, 2014
LH Stewart, Bart Ferguson, CJA Morgan et al.
28 citations
BACKGROUND: Acute recreational use of 3,4-methylenedioxymethamphetamine (MDMA; 'ecstasy') can promote pro-social effects which may alter interpersonal perceptions. AIMS: To explore such effects, this study investigated whether acute recreational use of ecstasy was associated with changes in individual perception of trustworthiness of people's faces and co-operative behaviours. METHOD: An...
Addiction
July 21, 2011
Celia J. A. Morgan, H. Valerie Curran
645 citations
AIMS: Ketamine remains an important medicine in both specialist anaesthesia and aspects of pain management. At the same time, its use as a recreational drug has spread in many parts of the world during the past few years. There are now increasing concerns about the harmful physical and psychological consequences of repeated misuse of this drug. The aim of this review was to survey and integrate...
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...
Human Psychopharmacology Clinical and Experimental
October 1, 2003
Suzanne L. Verheyden, John A. Henry, H. Valerie Curran
171 citations
Abstract This study examined the reported psychological effects of different patterns of MDMA use in men and women, and how they are modified by use of other psychoactive substances. A semi‐structured interview was conducted with 466 regular MDMA users, exploring the perceived acute, sub‐acute and long‐term subjective effects of this drug. Factor analysis established three main categories of...