Psychological Medicine
October 2, 2017
André Schmidt, Felix Müller, Claudia Lenz et al.
62 citations
Abstract Background Recent evidence shows that the serotonin 2A receptor (5-hydroxytryptamine2A receptor, 5-HT 2A R) is critically involved in the formation of visual hallucinations and cognitive impairments in lysergic acid diethylamide (LSD)-induced states and neuropsychiatric diseases. However, the interaction between 5-HT 2A R activation, cognitive impairments and visual hallucinations is...
Psychological Medicine
August 25, 2017
Philip J. Cowen
38 citations
Pragmatic studies indicate that a substantial number of depressed patients do not remit with current first-line antidepressant treatments and after two failed treatment steps the chance of remission with subsequent therapies is around 15%. This paper focuses on current evidence for pharmacological treatments in resistant depression as well as possible future developments. For patients who have...
Psychological Medicine
December 29, 2016
Rebecca S. Crane, Judson A. Brewer, Christina Feldman et al.
861 citations
There has been an explosion of interest in mindfulness-based programs (MBPs) such as Mindfulness-Based Stress Reduction (MBSR) and Mindfulness-Based Cognitive Therapy. This is demonstrated in increased research, implementation of MBPs in healthcare, educational, criminal justice and workplace settings, and in mainstream interest. For the sustainable development of the field there is a need to...
Psychological Medicine
March 3, 2016
Ravi Das, Amanda J. F. Tamman, Viktoriya L. Nikolova et al.
48 citations
BACKGROUND: Post-traumatic stress disorder (PTSD) involves maladaptive long-term memory formation which underlies involuntary intrusive thoughts about the trauma. Preventing the development of such maladaptive memory is a key aim in preventing the development of PTSD. We examined whether the N-methyl d-aspartate receptor (NMDAR) antagonist gas nitrous oxide (N2O) could reduce the frequency of...
Psychological Medicine
February 12, 2016
Taishiro Kishimoto, J. M. Chawla, K. Hagi et al.
363 citations
Background Ketamine and non-ketamine N-methyl-d-aspartate receptor antagonists (NMDAR antagonists) recently demonstrated antidepressant efficacy for the treatment of refractory depression, but effect sizes, trajectories and possible class effects are unclear. Method We searched PubMed/PsycINFO/Web of Science/clinicaltrials.gov until 25 August 2015. Parallel-group or cross-over randomized...
Psychological Medicine
February 5, 2016
Robin Carhart-Harris, Mendel Kaelen, Mark Bolstridge et al.
301 citations
Background Lysergic acid diethylamide (LSD) is a potent serotonergic hallucinogen or psychedelic that modulates consciousness in a marked and novel way. This study sought to examine the acute and mid-term psychological effects of LSD in a controlled study. Method A total of 20 healthy volunteers participated in this within-subjects study. Participants received LSD (75 µ g, intravenously) on one...
Psychological Medicine
August 12, 2015
James W. Murrough, Laili Soleimani, Kaitlin E. DeWilde et al.
297 citations
BACKGROUND: Suicide is a devastating public health problem and very few biological treatments have been found to be effective for quickly reducing the intensity of suicidal ideation (SI). We have previously shown that a single dose of ketamine, a glutamate N-methyl-d-aspartate (NMDA) receptor antagonist, is associated with a rapid reduction in depressive symptom severity and SI in patients with...
Psychological Medicine
May 24, 2013
James Stone, Helen L. Fisher, Barnaby Major et al.
69 citations
BACKGROUND: Cannabis use has been reported to be associated with an earlier onset of symptoms in patients with first-episode psychosis, and a worse outcome in those who continue to take cannabis. In general, studies have concentrated on symptoms of psychosis rather than mania. In this study, using a longitudinal design in a large naturalistic cohort of patients with first-episode psychosis, we...
Psychological Medicine
November 1, 2012
E. M. Marks, C. Steel, E. R. Peters
20 citations
BackgroundIntrusions are common symptoms of both post-traumatic stress disorder (PTSD) and schizophrenia. It has been suggested that an information processing style characterized by weak trait contextual integration renders psychotic individuals vulnerable to intrusive experiences. This ‘contextual integration hypothesis’ was tested in individuals reporting anomalous experiences in the absence...
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...
Psychological Medicine
February 1, 2012
C. J. A. Morgan, C. Gardener, G. Schafer et al.
Background Cannabis varies considerably in levels of its two major constituent cannabinoids – (delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Recently, we found evidence that those who smoked cannabis containing detectable levels of CBD had fewer psychotic-like symptoms than those whose cannabis had no CBD. The present study aimed, first, to replicate those findings and, second, to...
Psychological Medicine
November 1, 2011
J E Houston, J Murphy, M Shevlin et al.
Cannabis consumption continues to be identified as a causal agent in the onset and development of psychosis. However, recent findings have shown that the effect of cannabis on psychosis may be moderated by childhood traumatic experiences. Using hierarchical multivariate logistic analyses the current study examined both the independent effect of cannabis consumption on psychosis diagnosis and...
Psychological Medicine
October 1, 2011
R. Kuepper, J. Van Os, R. Lieb et al.
BackgroundCannabis use is considered a component cause of psychotic illness, interacting with genetic and other environmental risk factors. Little is known, however, about these putative interactions. The present study investigated whether an urban environment plays a role in moderating the effects of adolescent cannabis use on psychosis risk.MethodProspective data (n=1923, aged 14–24 years at...
Psychological Medicine
August 1, 2010
S C Linden, M Harris, C Whitaker et al.
Psychotic symptoms have been linked to religious experience, but empirical evidence is scarce. We have investigated the impact of the Welsh religious revival (RR) of 1904-1905 on the number of admissions to the regional psychiatric hospital, their diagnostic features and lifelong course. All case-notes of patients admitted to the North Wales Hospital between 1902 and 1907 were included. There...
Psychological Medicine
December 9, 2009
Jiřı́ Horáček, Martin Brunovský, Tomáš Novák et al.
42 citations
BACKGROUND: Theta cordance is a novel quantitative electroencephalography (QEEG) measure that correlates with cerebral perfusion. A series of clinical studies has demonstrated that the prefrontal theta cordance value decreases after 1 week of treatment in responders to antidepressants and that this effect precedes clinical improvement. Ketamine, a non-competitive antagonist of...
Psychological Medicine
November 27, 2009
Alberto Chiesa, Alessandro Serretti
752 citations
BACKGROUND: Mindfulness meditation (MM) practices constitute an important group of meditative practices that have received growing attention. The aim of the present paper was to systematically review current evidence on the neurobiological changes and clinical benefits related to MM practice in psychiatric disorders, in physical illnesses and in healthy subjects. METHOD: A literature search was...
Psychological Medicine
July 23, 2009
Rocío Martín‐Santos, Ana B. Fagundo, José Alexandre S. Crippa et al.
207 citations
BACKGROUND: We conducted a systematic review to assess the evidence for specific effects of cannabis on brain structure and function. The review focuses on the cognitive changes associated with acute and chronic use of the drug. METHOD: We reviewed literature reporting neuroimaging studies of chronic or acute cannabis use published up until January 2009. The search was conducted using Medline,...
Psychological Medicine
June 1, 2009
O. Mason, C. J. A. Morgan, S. K. Dhiman et al.
BackgroundEpidemiological evidence suggests a link between cannabis use and psychosis. A variety of factors have been proposed to mediate an individual's vulnerability to the harmful effects of the drug, one of which is their psychosis proneness. We hypothesized that highly psychosis-prone individuals would report more marked psychotic experiences under the acute influence of cannabis.MethodA...
Psychological Medicine
September 1, 2008
G. Bedi, J. Redman
68 citations
BackgroundAlthough there have been several reports linking ecstasy use with lowered cognitive function, much previous research suffers from substantial methodological limitations. The present study aimed to examine associations between ecstasy use and higher-level cognitive functions, using a larger sample size than most previous research and better controlling for a range of potential...
Psychological Medicine
September 1, 2008
E. Barkus, S. Lewis
BackgroundThe relationship between cannabis use and psychosis is still a matter for debate. Accounting for the individual differences in subjective experiences to recreational cannabis use in the general population may hold some clues to the aetiological relationship between cannabis and psychotic symptoms. We hypothesized that schizotypy would account for the individual differences in...
Psychological Medicine
July 1, 2007
Louisa Degenhardt, Chris Tennant, Stuart Gilmour et al.
The aim was to examine the temporal relationships over 10 months between cannabis use and symptoms of psychosis and depression in people with schizophrenia and related disorders. The design was a prospective study of 101 patients with schizophrenia and related disorders who were assessed monthly over 10 months on medication compliance, cannabis and other drug use, symptoms of depression and...
Psychological Medicine
April 1, 2007
Audrey Cougnard, Machteld Marcelis, Inez Myin-Germeys et al.
Background. Research suggests that low-grade psychotic experiences in the general population are a common but transitory developmental phenomenon. Using two independent general population samples, the hypothesis was examined that common, non-clinical developmental expression of psychosis may become abnormally persistent when synergistically combined with developmental exposures that may impact...
Psychological Medicine
October 1, 2005
Mauricio Sierra, Dawn Baker, Nicholas Medford et al.
Background. Depersonalization has long been considered a syndrome but there is poor agreement on its constituent symptoms.Method. In order to establish whether different symptoms of depersonalization represent the expression of a single or several underlying dimensions, an exploratory factor analysis on the Cambridge Depersonalization Scale (CDS) was carried out on 138 consecutive patients...
Psychological Medicine
January 28, 2004
Karen L. Hanson, Mónica Luciana
71 citations
Background. Use of MDMA (ecstasy), a serotonin neurotoxin, has been associated with memory impairment and psychological dysfunction. This study examined cognitive functioning in abstinent MDMA users and MDMA-naïve controls. Method. Participants completed measures of intelligence, motor function, attention, memory span, verbal fluency, immediate and delayed verbal memory, and working memory....
Psychological Medicine
2003
H. Verdoux, C. Gindre, F. Sorbara et al.
Background. Epidemiological findings suggest that cannabis use is a risk factor for the emergence of psychosis, and that the induction of psychotic symptoms in the context of cannabis use may be associated with a pre-existing vulnerability for psychosis. This study investigated in a non-clinical population the interaction between cannabis use and psychosis vulnerability in their effects on...