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Pelgrim TAD, Ramaekers JG, Wall MB, Freeman TP, Bossong MG. Acute effects of Δ9-tetrahydrocannabinol (THC) on resting state connectivity networks and impact of COMT genotype: A multi-site pharmacological fMRI study. Drug Alcohol Depend 2023; 251:110925. [PMID: 37598453 DOI: 10.1016/j.drugalcdep.2023.110925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 07/28/2023] [Accepted: 07/30/2023] [Indexed: 08/22/2023]
Abstract
BACKGROUND Cannabis produces various acute psychotropic effects, with marked individual differences. Cannabis use is a risk factor for developing psychotic disorders. The main component responsible for these effects is Δ9-tetrahydrocannabinol (THC). Here we investigated the neural basis of acute THC effects and its modulation by catechol-methyl-transferase (COMT) Val158Met genotype. METHODS Resting state functional MRI data of healthy occasional cannabis users were combined and re-analyzed from three double-blind, placebo-controlled, within-subject pharmacological functional magnetic resonance imaging studies (total N=87). Functional connectivity after placebo and THC was compared in three functional networks (salience, executive and default mode network) and a network implicated in psychosis (the hippocampus-midbrain-striatum network). COMT genotype modulation of subjective effects and connectivity was examined. RESULTS THC reduced connectivity in the salience network, specifically from the right insula to both the left insula and anterior cingulate cortex. We found a trend towards decreased connectivity in the hippocampus-midbrain-striatum network after THC. COMT genotype modulated subjective effects of THC, with strongest dysphoric reactions in Met/Met individuals. In addition, reduced connectivity after THC was demonstrated in the hippocampus-midbrain-striatum network of Met/Met individuals only. CONCLUSIONS In this large multisite study we found that THC robustly decreases connectivity in the salience network, involved in processing awareness and salient information. Connectivity changes in the hippocampus-midbrain-striatum network may reflect the acute psychotic-like effects of THC. COMT genotype modulation of THC's impact on subjective effects and functional connectivity provides further evidence for involvement of prefrontal dopamine levels in the acute effects of cannabis.
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Affiliation(s)
- Teuntje A D Pelgrim
- Department of Psychiatry, UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands; Department of Psychiatry, Parnassia Psychiatric Institute, Amsterdam, the Netherlands
| | - Johannes G Ramaekers
- Department of Neuropsychology & Psychopharmacology, Maastricht University, Maastricht, the Netherlands
| | - Matthew B Wall
- Invicro London, Hammersmith Hospital, London, UK; Faculty of Medicine, Imperial College London, London, UK; Clinical Psychopharmacology Unit, University College London, London, UK
| | - Tom P Freeman
- Addiction and Mental Health Group (AIM), University of Bath, Bath, UK
| | - Matthijs G Bossong
- Department of Psychiatry, UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands.
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Silczuk A, Smułek D, Kołodziej M, Gujska J. The Construct of Medical and Non-Medical Marijuana—Critical Review. IJERPH 2022; 19:2769. [PMID: 35270462 PMCID: PMC8910105 DOI: 10.3390/ijerph19052769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 02/19/2022] [Accepted: 02/23/2022] [Indexed: 11/17/2022]
Abstract
The rising popularity of medical marijuana and its potential therapeutic uses has resulted in passionate discussions that have mainly focused on its possible benefits and applications. Although the concept itself seems promising, the multitude of presented information has noticeable ramifications—terminological chaos being one. This work aimed to synthesize and critically analyze scientific evidence on the therapeutic uses of cannabinoids in the field of psychiatry. Emphasis was placed on the anxiolytic effects of cannabis constituents and their effects on post-traumatic stress disorder, anxiety disorders, schizophrenia spectrum, and other psychotic disorders. The review was carried out from an addictological perspective. A database search of interchangeably combined keywords resulted in the identification of subject-related records. The data were then analyzed in terms of relevance, contents, methodologies, and cited papers. The results were clear in supporting one common conclusion: while most findings provide support for beneficial applications of medical marijuana in psychiatry, no certain conclusions can be drawn until larger-scaled, more methodologically rigorous, and (preferably) controlled randomized trials verify these discoveries.
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Deligianni ML, Studer J, Gmel G, Khazaal Y, Bertholet N. Consciousness alterations in a cohort of young Swiss men: Associations with substance use and personality traits. Front Psychiatry 2022; 13:1056159. [PMID: 36683973 PMCID: PMC9846235 DOI: 10.3389/fpsyt.2022.1056159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 12/02/2022] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Substance-induced consciousness alterations (CA) have mainly been studied among users of psychedelics but not among people using street drugs. AIMS Explore occurrences of three different types of substance-induced CA [ego dissolution (ED), visual pseudo-hallucinations (VPH), anxiety/paranoia (A/P)] and their perceived influences on life, together with their associations with substance use and personality correlates in a general population sample of 25-year-old men. METHODS 2,796 young Swiss men lifetime substance users completed a self-report questionnaire including history of use (never, former, and current) of different substances categories (psychedelics, cocaine, psychostimulants, ecstasy, MDMA, and other drugs), substance-induced ego dissolution (ED), visual pseudo-hallucinations (VPH) and anxiety/paranoia (A/P), the influence of these CA experiences on life, and personality traits (sensation seeking, sociability, anxiety-neuroticism, and aggression-hostility). RESULTS 32.2% reported at least one CA (i.e., ED, VPH or A/P), with 20.5% reporting ED, 16.7% VPH, and 14.6% A/P. Former and current use of psychedelics and ketamine was significantly associated with occurrences of all three types of CAs and with a positive influence of CA on life. Associations between the former and current use of other substances and the different types of CA were less consistent, and perceived influences on life were not statistically significant. Sociability was negatively associated with occurrences of all three types of CA. Positive associations were found between anxiety-neuroticism and ED and A/P, between aggression-hostility and A/P, and between sensation seeking and ED and VPH. CONCLUSION This study supports the potential for psychedelics to induce CAs perceived as beneficial to life among people using street drugs, possibly reflecting the mechanism underlying the therapeutic potential of psychedelics.
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Affiliation(s)
- Marianthi Lousiana Deligianni
- Addiction Medicine, Department of Psychiatry, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
| | - Joseph Studer
- Addiction Medicine, Department of Psychiatry, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland.,Service of Adult Psychiatry North-West, Department of Psychiatry, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Gerhard Gmel
- Addiction Medicine, Department of Psychiatry, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland.,Research Department, Addiction Switzerland, Lausanne, Switzerland.,Centre for Addiction and Mental Health, Institute for Mental Health Policy Research, Toronto, ON, Canada.,Faculty of Health and Social Science, University of the West of England, Bristol, United Kingdom
| | - Yasser Khazaal
- Addiction Medicine, Department of Psychiatry, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland.,Research Centre, Montreal University Institute of Mental Health, Montreal, QC, Canada
| | - Nicolas Bertholet
- Addiction Medicine, Department of Psychiatry, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
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4
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Abstract
BACKGROUND Evidence suggests that an overlap exists between the neurobiology of psychotic disorders and the effects of cannabinoids on neurocognitive and neurochemical substrates involved in reward processing. AIMS We investigate whether the psychotomimetic effects of delta-9-tetrahydrocannabinol (THC) and the antipsychotic potential of cannabidiol (CBD) are underpinned by their effects on the reward system and dopamine. METHODS This narrative review focuses on the overlap between altered dopamine signalling and reward processing induced by cannabinoids, pre-clinically and in humans. A systematic search was conducted of acute cannabinoid drug-challenge studies using neuroimaging in healthy subjects and those with psychosis RESULTS: There is evidence of increased striatal presynaptic dopamine synthesis and release in psychosis, as well as abnormal engagement of the striatum during reward processing. Although, acute THC challenges have elicited a modest effect on striatal dopamine, cannabis users generally indicate impaired presynaptic dopaminergic function. Functional MRI studies have identified that a single dose of THC may modulate regions involved in reward and salience processing such as the striatum, midbrain, insular, and anterior cingulate, with some effects correlating with the severity of THC-induced psychotic symptoms. CBD may modulate brain regions involved in reward/salience processing in an opposite direction to that of THC. CONCLUSIONS There is evidence to suggest modulation of reward processing and its neural substrates by THC and CBD. Whether such effects underlie the psychotomimetic/antipsychotic effects of these cannabinoids remains unclear. Future research should address these unanswered questions to understand the relationship between endocannabinoid dysfunction, reward processing abnormalities, and psychosis.
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5
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Gunasekera B, Davies C, Martin-Santos R, Bhattacharyya S. The Yin and Yang of Cannabis: A Systematic Review of Human Neuroimaging Evidence of the Differential Effects of Δ 9-Tetrahydrocannabinol and Cannabidiol. Biol Psychiatry Cogn Neurosci Neuroimaging 2021; 6:636-645. [PMID: 33414100 DOI: 10.1016/j.bpsc.2020.10.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 09/14/2020] [Accepted: 10/19/2020] [Indexed: 12/23/2022]
Abstract
Cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) have been the most investigated cannabinoids at the human and preclinical levels, although the neurobiological mechanisms underlying their effects remain unclear. Human experimental evidence complemented by observational studies suggests that THC may have psychotogenic effects while CBD may have antipsychotic effects. However, whether their effects on brain function are consistent with their opposing behavioral effects remains unclear. To address this, here we synthesize neuroimaging evidence investigating the acute effects of THC and CBD on human brain function using a range of neuroimaging techniques, with an aim to identify the key brain substrates where THC and CBD have opposing effects. After a systematic search, a review of the available studies indicated marked heterogeneity. However, an overall pattern of opposite effect profiles of the two cannabinoids was evident with some degree of consistency, primarily attributed to the head-to-head challenge studies of THC and CBD. While head-to-head comparisons are relatively few, collectively the evidence suggests that opposite effects of THC and CBD may be present in the striatum, parahippocampus, anterior cingulate/medial prefrontal cortex, and amygdala, with opposite effects less consistently identified in other regions. Broadly, THC seems to increase brain activation and blood flow, whereas CBD seems to decrease brain activation and blood flow. Given the sparse evidence, there is a particular need to understand the mechanisms underlying their opposite behavioral effects because it may not only offer insights into the underlying pathophysiological mechanisms of psychotic disorders but also suggest potentially novel targets and biomarkers for drug discovery.
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Affiliation(s)
- Brandon Gunasekera
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom
| | - Cathy Davies
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom
| | - Rocio Martin-Santos
- Department of Medicine, Institute of Neuroscience, University of Barcelona, Spain
| | - Sagnik Bhattacharyya
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom.
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6
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Kunin-Batson AS, Klosky JL, Carlson-Green B, Brinkman TM. Health Behaviors and Neurocognitive Function in Survivors of Childhood Cancer. J Clin Oncol 2021; 39:1786-1794. [PMID: 33886366 DOI: 10.1200/jco.20.02512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
| | - James L Klosky
- Department of Pediatrics, Emory University School of Medicine & Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA
| | | | - Tara M Brinkman
- Departments of Epidemiology & Cancer Control and Psychology, St. Jude Children's Research Hospital
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7
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Cupo L, Plitman E, Guma E, Chakravarty MM. A systematic review of neuroimaging and acute cannabis exposure in age-of-risk for psychosis. Transl Psychiatry 2021; 11:217. [PMID: 33850098 DOI: 10.1038/s41398-021-01295-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 01/06/2021] [Accepted: 02/05/2021] [Indexed: 01/14/2023] Open
Abstract
Acute exposure to cannabis has been associated with an array of cognitive alterations, increased risk for neuropsychiatric illness, and other neuropsychiatric sequelae including the emergence of acute psychotic symptoms. However, the brain alterations associating cannabis use and these behavioral and clinical phenotypes remains disputed. To this end, neuroimaging can be a powerful technique to non-invasively study the impact of cannabis exposure on brain structure and function in both humans and animal models. While chronic exposure studies provide insight into how use may be related to long-term outcomes, acute exposure may reveal interesting information regarding the immediate impact of use and abuse on brain circuits. Understanding these alterations could reveal the connection with symptom dimensions in neuropsychiatric disorders and, more specifically with psychosis. The purpose of the present review is to: 1) provide an update on the findings of pharmacological neuroimaging studies examining the effects of administered cannabinoids and 2) focus the discussion on studies that examine the sensitive window for the emergence of psychosis. Current literature indicates that cannabis exposure has varied effects on the brain, with the principal compounds in cannabis (delta-9-tetrahydrocannabinol and cannabidiol) altering activity across different brain regions. Importantly, we also discovered critical gaps in the literature, particularly regarding sex-dependent responses and long-term effects of chronic exposure. Certain networks often characterized as dysregulated in psychosis, like the default mode network and limbic system, were also impacted by THC exposure, identifying areas of particular interest for future work investigating the potential relationship between the two.
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8
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Abstract
Background: Cannabis is known to have a broad range of effects on behavior, including experiencing a "high" and tranquility/relaxation. However, there are several adverse behavioral sequalae that can arise from cannabis use, depending on frequency of use, potency (e.g., THC content), age of onset, and cumulative exposure. This systematic review examined evidence for cannabis-related adverse behavioral sequalae in otherwise healthy human subjects. Methods: Following PRISMA guidelines, we conducted a systematic review of cross-sectional and longitudinal studies from 1990 to 2020 that identified cannabis-related adverse behavioral outcomes in subjects without psychiatric and medical co-morbidities from PubMed and PsychInfo searches. Key search terms included "cannabis" OR "tetrahydrocannabinol" OR "cannabidiol" OR "marijuana" AND "anxiety" OR "depression" OR "psychosis" OR "schizophrenia" "OR "IQ" OR "memory" OR "attention" OR "impulsivity" OR "cognition" OR "education" OR "occupation". Results: Our search detected a total of 2,870 studies, from which we extracted 124 relevant studies from the literature on cannabis effects in the non-clinical population. Effects of cannabis on several behavioral sequelae including cognition, motivation, impulsivity, mood, anxiety, psychosis intelligence, and psychosocial functioning were identified. The preponderance of the evidence suggests that frequency of cannabis use, THC (but not CBD) content, age of onset, and cumulative cannabis exposure can all contribute to these adverse outcomes in individuals without a pre-existing medical condition or psychiatric disorder. The strongest evidence for the negative effects of cannabis are for psychosis and psychosocial functioning. Conclusions: Although more research is needed to determine risk factors for development of adverse behavioral sequelae of cannabis use, these findings underline the importance of understanding vulnerability to the adverse effects of cannabis, which has implications for prevention and treatment of problematic cannabis use.
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Affiliation(s)
- Maryam Sorkhou
- Addictions Division, Centre for Addiction and Mental Health (CAMH), University of Toronto, Toronto, ON, Canada.,Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Rachel H Bedder
- Department of Psychology, Ryerson University, Toronto, ON, Canada
| | - Tony P George
- Addictions Division, Centre for Addiction and Mental Health (CAMH), University of Toronto, Toronto, ON, Canada.,Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada.,Department of Psychiatry, University of Toronto, Toronto, ON, Canada
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9
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Halladay JE, MacKillop J, Munn C, Jack SM, Georgiades K. Cannabis Use as a Risk Factor for Depression, Anxiety, and Suicidality: Epidemiological Associations and Implications for Nurses. J Addict Nurs 2020; 31:92-101. [PMID: 32487935 DOI: 10.1097/JAN.0000000000000334] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Psychiatric disorders and substance use disorders commonly co-occur and are major public health concerns given the morbidity and mortality associated with them. Globally, cannabis is among the most commonly used drugs, and cannabis use frequently begins in adolescence or emerging adulthood, both important periods of development and periods in which psychiatric symptoms and disorders frequently emerge. Thus, the relationships between cannabis use and mental illnesses are essential for nurses and other healthcare professionals and researchers to explore and understand. This literature review examines the relationships between cannabis use and depression, anxiety, and suicide. It includes a primer on the neurobiology of cannabis effects; an overview on the epidemiological evidence on the associations between cannabis use and depression, anxiety, and suicide; and a discussion of implications for nurses, particularly important given changes in the medical and recreational cannabis legislation in North America. Overall, this review found consistent evidence showing a cross-sectional association between recreational cannabis use and depression, anxiety, and suicide, despite some limitations and conflicts in the literature. In addition, most evidence from longitudinal or case control studies suggested cannabis use preceded the development of depressive symptoms and suicidal behaviors, although the quality of this evidence was mixed. Implications for future research and nursing practice are discussed.
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10
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Rabinak CA, Blanchette A, Zabik NL, Peters C, Marusak HA, Iadipaolo A, Elrahal F. Cannabinoid modulation of corticolimbic activation to threat in trauma-exposed adults: a preliminary study. Psychopharmacology (Berl) 2020; 237:1813-1826. [PMID: 32162103 PMCID: PMC7244361 DOI: 10.1007/s00213-020-05499-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 02/28/2020] [Indexed: 11/25/2022]
Abstract
RATIONALE Excessive fear and anxiety, coupled with corticolimbic dysfunction, are core features of stress- and trauma-related psychopathology, such as posttraumatic stress disorder (PTSD). Interestingly, low doses of ∆9-tetrahydrocannabinol (THC) can produce anxiolytic effects, reduce threat-related amygdala activation, and enhance functional coupling between the amygdala and medial prefrontal cortex and adjacent rostral cingulate cortex (mPFC/rACC) during threat processing in healthy adults. Together, these findings suggest the cannabinoid system as a potential pharmacological target in the treatment of excess fear and anxiety. However, the effects of THC on corticolimbic functioning in response to threat have not be investigated in adults with trauma-related psychopathology. OBJECTIVE To address this gap, the present study tests the effects of an acute low dose of THC on corticolimbic responses to threat in three groups of adults: (1) non-trauma-exposed healthy controls (HC; n = 25), (2) trauma-exposed adults without PTSD (TEC; n = 27), and (3) trauma-exposed adults with PTSD (n = 19). METHODS Using a randomized, double-blind, placebo-controlled, between-subjects design, 71 participants were randomly assigned to receive either THC or placebo (PBO) and subsequently completed a well-established threat processing paradigm during functional magnetic resonance imaging. RESULTS In adults with PTSD, THC lowered threat-related amygdala reactivity, increased mPFC activation during threat, and increased mPFC-amygdala functional coupling. CONCLUSIONS These preliminary data suggest that THC modulates threat-related processing in trauma-exposed individuals with PTSD, which may prove advantageous as a pharmacological approach to treating stress- and trauma-related psychopathology.
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Affiliation(s)
- Christine A Rabinak
- Department of Pharmacy Practice, Wayne State University, 259 Mack Ave, Suite 2190, Detroit, MI, 48201, USA.
- Translational Neuroscience Program, Wayne State University, Detroit, MI, USA.
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University, Detroit, MI, USA.
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, MI, USA.
- Merrill Palmer Skillman Institute for Child and Family Development, Wayne State University, Detroit, MI, USA.
| | - Ashley Blanchette
- Department of Pharmacy Practice, Wayne State University, 259 Mack Ave, Suite 2190, Detroit, MI, 48201, USA
| | - Nicole L Zabik
- Department of Pharmacy Practice, Wayne State University, 259 Mack Ave, Suite 2190, Detroit, MI, 48201, USA
- Translational Neuroscience Program, Wayne State University, Detroit, MI, USA
| | - Craig Peters
- Department of Pharmacy Practice, Wayne State University, 259 Mack Ave, Suite 2190, Detroit, MI, 48201, USA
| | - Hilary A Marusak
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University, Detroit, MI, USA
- Merrill Palmer Skillman Institute for Child and Family Development, Wayne State University, Detroit, MI, USA
| | - Allesandra Iadipaolo
- Department of Pharmacy Practice, Wayne State University, 259 Mack Ave, Suite 2190, Detroit, MI, 48201, USA
| | - Farrah Elrahal
- Department of Pharmacy Practice, Wayne State University, 259 Mack Ave, Suite 2190, Detroit, MI, 48201, USA
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11
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Daniju Y, Bossong MG, Brandt K, Allen P. Do the effects of cannabis on the hippocampus and striatum increase risk for psychosis? Neurosci Biobehav Rev 2020; 112:324-335. [PMID: 32057817 DOI: 10.1016/j.neubiorev.2020.02.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 01/17/2020] [Accepted: 02/10/2020] [Indexed: 11/19/2022]
Abstract
Cannabis use is associated with increased risk of psychotic symptoms and in a small number of cases it can lead to psychoses. This review examines the neurobiological mechanisms that mediate the link between cannabis use and psychosis risk. We use an established preclinical model of psychosis, the methylazoxymethanol acetate (MAM) rodent model, as a framework to examine if psychosis risk in some cannabis users is mediated by the effects of cannabis on the hippocampus, and this region's role in the regulation of mesolimbic dopamine. We also examine how cannabis affects excitatory neurotransmission known to regulate hippocampal neural activity and output. Whilst there is clear evidence that cannabis/cannabinoids can affect hippocampal and medial temporal lobe function and structure, the evidence that cannabis/cannabinoids increase striatal dopamine function is less robust. There is limited evidence that cannabis use affects cortical and striatal glutamate levels, but there are currently too few studies to draw firm conclusions. Future work is needed to test the MAM model in relation to cannabis using multimodal neuroimaging approaches.
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Affiliation(s)
- Y Daniju
- Department of Psychology, University of Roehampton, London, UK
| | - M G Bossong
- Department of Psychiatry, UMC Utrecht Brain Center, University Medical Center Utrecht, the Netherlands
| | - K Brandt
- Department of Psychology, University of Roehampton, London, UK
| | - P Allen
- Department of Psychology, University of Roehampton, London, UK; Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK; Icahn School of Medicine at Mount Sinai Hospital, New York, USA.
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12
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LaFrance EM, Stueber A, Glodosky NC, Mauzay D, Cuttler C. Overbaked: assessing and predicting acute adverse reactions to Cannabis. J Cannabis Res 2020; 2:3. [PMID: 33526120 PMCID: PMC7819287 DOI: 10.1186/s42238-019-0013-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Accepted: 12/18/2019] [Indexed: 11/17/2022] Open
Abstract
Background Trends toward legalizing cannabis may increase experimentation with the drug among less experienced users with limited knowledge of possible adverse reactions. This study explores the prevalence, frequency, and levels of distress produced by various acute adverse reactions to cannabis, as well as predictors of these reactions. Methods The Adverse Reactions Scale (ARS) was created and administered to a large sample of undergraduate college students (n = 999) who were predominantly white (> 70%), female (> 70%), recreational (> 90%) cannabis users. The ARS was administered in an anonymous online survey measuring demographics, cannabis use patterns, cannabis use motives, personality, and negative affect. Results The most prevalent adverse reactions to cannabis were coughing fits, anxiety, and paranoia, which > 50% of the sample reported experiencing. The most frequently occurring reactions were coughing fits, chest/lung discomfort, and body humming, which occurred on approximately 30–40% of cannabis use sessions. Panic attacks, fainting, and vomiting were rated as the most distressing, with mean ratings falling between “moderately” and “quite” distressing. Multiple regression analyses revealed that lower frequency of cannabis use predicted increased frequency of adverse reactions. Symptoms of cannabis use disorder, conformity motives, and anxiety sensitivity were significant predictors of both the prevalence of, and distress caused by, adverse reactions. Conclusions Relative to past research, this study provides a more comprehensive account of possible adverse reactions to cannabis, and individual difference variables that predict these reactions. This study has implications for inexperienced cannabis users, as well as medical professionals and budtenders who provide information about cannabis use.
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Affiliation(s)
- Emily M LaFrance
- Department of Psychology, Washington State University, P.O. Box 644820, Pullman, WA, 99164-4820, USA.
| | - Amanda Stueber
- Department of Psychology, Washington State University, P.O. Box 644820, Pullman, WA, 99164-4820, USA
| | - Nicholas C Glodosky
- Department of Psychology, Washington State University, P.O. Box 644820, Pullman, WA, 99164-4820, USA
| | - Dakota Mauzay
- Department of Psychology, Washington State University, P.O. Box 644820, Pullman, WA, 99164-4820, USA
| | - Carrie Cuttler
- Department of Psychology, Washington State University, P.O. Box 644820, Pullman, WA, 99164-4820, USA.,Translational Addiction Research Center, Washington State University, Pullman, WA, USA
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13
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Workman CD, Kindred JH, Boles Ponto LL, Kamholz J, Rudroff T. The effects of chronic Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) use on cerebral glucose metabolism in multiple sclerosis: a pilot study. Appl Physiol Nutr Metab 2019; 45:450-452. [PMID: 31841355 DOI: 10.1139/apnm-2019-0634] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
This exploratory pilot study investigated the effects of chronic Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) on cerebral glucose metabolism in people with multiple sclerosis (PwMS). Compared with nonusers, THC users had hypermetabolism of 3 regions (p < 0.039, d >1.17) in left temporal areas, while CBD users had hypometabolism of 5 regions (p < 0.032, d > 1.31) in left temporal areas. This study highlights the need to discriminate between THC and CBD in future cannabis studies. Novelty Chronic THC and CBD use had disparate effects on cerebral glucose metabolism in PwMS.
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Affiliation(s)
- Craig D Workman
- Department of Health and Human Physiology, University of Iowa, Iowa City, IA 52242, USA
| | - John H Kindred
- Department of Physical Therapy, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Laura L Boles Ponto
- Department of Radiology, University of Iowa Health Clinics, Iowa City, IA 52242, USA
| | - John Kamholz
- Department of Neurology, University of Iowa Health Clinics, Iowa City, IA 52242, USA
| | - Thorsten Rudroff
- Department of Health and Human Physiology, University of Iowa, Iowa City, IA 52242, USA.,Department of Neurology, University of Iowa Health Clinics, Iowa City, IA 52242, USA
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Blithikioti C, Miquel L, Batalla A, Rubio B, Maffei G, Herreros I, Gual A, Verschure P, Balcells‐Oliveró M. Cerebellar alterations in cannabis users: A systematic review. Addict Biol 2019; 24:1121-1137. [PMID: 30811097 DOI: 10.1111/adb.12714] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 12/13/2018] [Accepted: 12/13/2018] [Indexed: 01/18/2023]
Abstract
Cannabis is the most used illicit substance in the world. As many countries are moving towards decriminalization, it is crucial to determine whether and how cannabis use affects human brain and behavior. The role of the cerebellum in cognition, emotion, learning, and addiction is increasingly recognized. Because of its high density in CB1 receptors, it is expected to be highly affected by cannabis use. The aim of this systematic review is to investigate how cannabis use affects cerebellar structure and function, as well as cerebellar-dependent behavioral tasks. Three databases were searched for peer-reviewed literature published until March 2018. We included studies that focused on cannabis effects on cerebellar structure, function, or cerebellar-dependent behavioral tasks. A total of 348 unique records were screened, and 40 studies were included in the qualitative synthesis. The most consistent findings include (1) increases in cerebellar gray matter volume after chronic cannabis use, (2) alteration of cerebellar resting state activity after acute or chronic use, and (3) deficits in memory, decision making, and associative learning. Age of onset and higher exposure to cannabis use were frequently associated with increased cannabis-induced alterations. Chronic cannabis use is associated with alterations in cerebellar structure and function, as well as with deficits in behavioral paradigms that involve the cerebellum (eg, eyeblink conditioning, memory, and decision making). Future studies should consider tobacco as confounding factor and use standardized methods for assessing cannabis use. Paradigms exploring the functional activity of the cerebellum may prove useful as monitoring tools of cannabis-induced impairment.
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Affiliation(s)
- Chrysanthi Blithikioti
- Grup de Recerca en Addiccions Clínic (GRAC)Institut Clínic de Neurociències Barcelona Spain
- IDIBAPSInstitut d'Investigacions Biomèdiques August Pi i Sunyer Barcelona Spain
- Hospital ClínicUniversitat de Barcelona Barcelona Spain
| | - Laia Miquel
- Grup de Recerca en Addiccions Clínic (GRAC)Institut Clínic de Neurociències Barcelona Spain
- IDIBAPSInstitut d'Investigacions Biomèdiques August Pi i Sunyer Barcelona Spain
- Hospital ClínicUniversitat de Barcelona Barcelona Spain
| | - Albert Batalla
- Department of Psychiatry, Brain Center Rudolf MagnusUniversity Medical Center Utrecht Utrecht the Netherlands
- Nijmegen Institute for Scientist‐Practitioners in Addiction (NISPA)Radboud University Nijmegen The Netherlands
| | - Belen Rubio
- Laboratory of Synthetic Perceptive, Emotive and Cognitive SystemsInstitute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology Barcelona Spain
| | - Giovanni Maffei
- Laboratory of Synthetic Perceptive, Emotive and Cognitive SystemsInstitute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology Barcelona Spain
| | - Ivan Herreros
- Laboratory of Synthetic Perceptive, Emotive and Cognitive SystemsInstitute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology Barcelona Spain
| | - Antoni Gual
- Grup de Recerca en Addiccions Clínic (GRAC)Institut Clínic de Neurociències Barcelona Spain
- IDIBAPSInstitut d'Investigacions Biomèdiques August Pi i Sunyer Barcelona Spain
- Hospital ClínicUniversitat de Barcelona Barcelona Spain
| | - Paul Verschure
- Laboratory of Synthetic Perceptive, Emotive and Cognitive SystemsInstitute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology Barcelona Spain
- ICREAInstitucio Catalana de Recerca I Estudis Avançats, Passeig Lluis Companys Barcelona Spain
| | - Mercedes Balcells‐Oliveró
- Grup de Recerca en Addiccions Clínic (GRAC)Institut Clínic de Neurociències Barcelona Spain
- IDIBAPSInstitut d'Investigacions Biomèdiques August Pi i Sunyer Barcelona Spain
- Hospital ClínicUniversitat de Barcelona Barcelona Spain
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15
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Burggren AC, Shirazi A, Ginder N, London ED. Cannabis effects on brain structure, function, and cognition: considerations for medical uses of cannabis and its derivatives. Am J Drug Alcohol Abuse 2019; 45:563-579. [PMID: 31365275 PMCID: PMC7027431 DOI: 10.1080/00952990.2019.1634086] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 06/14/2019] [Accepted: 06/17/2019] [Indexed: 12/16/2022]
Abstract
Background: Cannabis is the most widely used illicit substance worldwide, and legalization for recreational and medical purposes has substantially increased its availability and use in the United States.Objectives: Decades of research have suggested that recreational cannabis use confers risk for cognitive impairment across various domains, and structural and functional differences in the brain have been linked to early and heavy cannabis use.Methods: With substantial evidence for the role of the endocannabinoid system in neural development and understanding that brain development continues into early adulthood, the rising use of cannabis in adolescents and young adults raises major concerns. Yet some formulations of cannabinoid compounds are FDA-approved for medical uses, including applications in children.Results: Potential effects on the trajectory of brain morphology and cognition, therefore, should be considered. The goal of this review is to update and consolidate relevant findings in order to inform attitudes and public policy regarding the recreational and medical use of cannabis and cannabinoid compounds.Conclusions: The findings point to considerations for age limits and guidelines for use.
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Affiliation(s)
- Alison C Burggren
- Robert and Beverly Lewis Center for Neuroimaging, University of Oregon, Eugene, OR, USA
| | - Anaheed Shirazi
- Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA, USA
| | - Nathaniel Ginder
- Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA, USA
| | - Edythe D. London
- Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA, USA
- Department of Molecular and Medical Pharmacology, and the Brain Research Institute, University of California at Los Angeles, Los Angeles, CA, USA
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16
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Zaytseva Y, Horáček J, Hlinka J, Fajnerová I, Androvičová R, Tintěra J, Salvi V, Balíková M, Hložek T, Španiel F, Páleníček T. Cannabis-induced altered states of consciousness are associated with specific dynamic brain connectivity states. J Psychopharmacol 2019; 33:811-821. [PMID: 31154891 DOI: 10.1177/0269881119849814] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Cannabis, and specifically one of its active compounds delta-9-tetrahydrocannabinol in recreational doses, has a variety of effects on cognitive processes. Most studies employ resting state functional magnetic resonance imaging techniques to assess the stationary effects of cannabis and to-date one report addressed the impact of delta-9-tetrahydrocannabinol on the dynamics of whole-brain functional connectivity. METHODS Using a repeated-measures, within-subjects design, 19 healthy occasional cannabis users (smoking cannabis ⩽2 per week) underwent resting state functional magnetic resonance imaging scans. Each subject underwent two scans: in the intoxicated condition, shortly after smoking a cannabis cigarette, and in the non-intoxicated condition, with the subject being free from cannabinoids for at least one week before. All sessions were randomized and performed in a four-week interval. Data were analysed employing a standard independent component analysis approach with subsequent tracking of the functional connectivity dynamics, which allowed six connectivity clusters (states) to be individuated. RESULTS Using standard independent component analysis in resting state functional connectivity, a group effect was found in the precuneus connectivity. With a dynamic independent component analysis approach, we identified one transient connectivity state, characterized by high connectivity within and between auditory and somato-motor cortices and anti-correlation with subcortical structures and the cerebellum that was only found during the intoxicated condition. Behavioural measures of the subjective experiences of changed perceptions and tetrahydrocannabinol plasma levels during intoxication were associated with this state. CONCLUSIONS With the help of the dynamic connectivity approach we could elucidate neural correlates of the transitory perceptual changes induced by delta-9-tetrahydrocannabinol in cannabis users, and possibly identify a biomarker of cannabis intoxication.
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Affiliation(s)
- Yuliya Zaytseva
- 1 National Institute of Mental Health, Klecany, Czech Republic.,3 Human Science Centre, Ludwig-Maximilian University, Munich, Germany
| | - Jiří Horáček
- 1 National Institute of Mental Health, Klecany, Czech Republic.,2 3rd Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
| | - Jaroslav Hlinka
- 1 National Institute of Mental Health, Klecany, Czech Republic.,4 Institute of Computer Science, Czech Academy of Sciences, Prague, Czech Republic
| | - Iveta Fajnerová
- 1 National Institute of Mental Health, Klecany, Czech Republic.,2 3rd Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
| | - Renata Androvičová
- 1 National Institute of Mental Health, Klecany, Czech Republic.,2 3rd Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
| | | | - Virginio Salvi
- 5 Department of Neuroscience, ASST Fatebenefratelli Sacco, Milan, Italy
| | - Marie Balíková
- 6 Institute of Forensic Medicine and Toxicology, Charles University in Prague, Czech Republic
| | - Tomáš Hložek
- 6 Institute of Forensic Medicine and Toxicology, Charles University in Prague, Czech Republic
| | - Filip Španiel
- 1 National Institute of Mental Health, Klecany, Czech Republic.,2 3rd Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
| | - Tomáš Páleníček
- 1 National Institute of Mental Health, Klecany, Czech Republic.,2 3rd Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
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Bossong MG, van Hell HH, Schubart CD, van Saane W, Iseger TA, Jager G, van Osch MJP, Jansma JM, Kahn RS, Boks MP, Ramsey NF. Acute effects of ∆9-tetrahydrocannabinol (THC) on resting state brain function and their modulation by COMT genotype. Eur Neuropsychopharmacol 2019; 29:766-776. [PMID: 30975584 DOI: 10.1016/j.euroneuro.2019.03.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 01/30/2019] [Accepted: 03/22/2019] [Indexed: 01/07/2023]
Abstract
Cannabis produces a broad range of acute, dose-dependent psychotropic effects. Only a limited number of neuroimaging studies have mapped these effects by examining the impact of cannabis on resting state brain neurophysiology. Moreover, how genetic variation influences the acute effects of cannabis on resting state brain function is unknown. Here we investigated the acute effects of ∆9-tetrahydrocannabinol (THC), the main psychoactive constituent of cannabis, on resting state brain neurophysiology, and their modulation by catechol-methyl-transferase (COMT) Val158Met genotype. Thirty-nine healthy volunteers participated in a pharmacological MRI study, where we applied Arterial Spin Labelling (ASL) to measure perfusion and functional MRI to assess resting state connectivity. THC increased perfusion in bilateral insula, medial superior frontal cortex, and left middle orbital frontal gyrus. This latter brain area showed significantly decreased connectivity with the precuneus after THC administration. THC effects on perfusion in the left insula were significantly related to subjective changes in perception and relaxation. These findings indicate that THC enhances metabolism and thus neural activity in the salience network. Furthermore, results suggest that recruitment of brain areas within this network is involved in the acute effects of THC. Resting state perfusion was modulated by COMT genotype, indicated by a significant interaction effect between drug and genotype on perfusion in the executive network, with increased perfusion after THC in Val/Met heterozygotes only. This finding suggests that prefrontal dopamine levels are involved in the susceptibility to acute effects of cannabis.
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Affiliation(s)
- Matthijs G Bossong
- Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands; Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands; Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, London SE5 8AF, United Kingdom.
| | - Hendrika H van Hell
- Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands; Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
| | - Chris D Schubart
- Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands; Department of Psychiatry, Tergooi Hospital, Van Riebeeckweg 212, 1213 XZ Hilversum, The Netherlands
| | - Wesley van Saane
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, London SE5 8AF, United Kingdom
| | - Tabitha A Iseger
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, London SE5 8AF, United Kingdom; Department of Experimental Psychology, Utrecht University, Heidelberglaan 1, 3584 CS Utrecht, The Netherlands; Research Institute Brainclinics, Bijleveldsingel 32, 6524 AD Nijmegen, The Netherlands
| | - Gerry Jager
- Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands; Division of Human Nutrition, Wageningen University, Bomenweg 2, 6703 HD, Wageningen, The Netherlands
| | - Matthias J P van Osch
- Department of Radiology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - J Martijn Jansma
- Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands; Department of Neurosurgery, Elisabeth-TweeSteden Hospital, Tilburg, The Netherlands
| | - René S Kahn
- Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands; Department of Psychiatry, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1230, New York, NY 10029-6574, United States
| | - Marco P Boks
- Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
| | - Nick F Ramsey
- Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
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19
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Bhattacharyya S, Sainsbury T, Allen P, Nosarti C, Atakan Z, Giampietro V, Brammer M, McGuire PK. Increased hippocampal engagement during learning as a marker of sensitivity to psychotomimetic effects of δ-9-THC. Psychol Med 2018; 48:2748-2756. [PMID: 29502548 DOI: 10.1017/s0033291718000387] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND Cannabis and its main psychoactive ingredient δ-9-tetrahydrocannibidiol (THC) can induce transient psychotic symptoms in healthy individuals and exacerbate them in those with established psychosis. However, not everyone experience these effects, suggesting that certain individuals are particularly susceptible. The neural basis of this sensitivity to the psychotomimetic effects of THC is unclear. METHODS We investigated whether individuals who are sensitive to the psychotomimetic effects of THC (TP) under experimental conditions would show differential hippocampal activation compared with those who are not (NP). We studied 36 healthy males under identical conditions under the influence of placebo or THC (10 mg) given orally, on two separate occasions, in a pseudo-randomized, double-blind, repeated measures, within-subject, cross-over design, using psychopathological assessments and functional MRI while they performed a verbal learning task. They were classified into those who experienced transient psychotic symptoms (TP; n = 14) following THC administration and those who did not (NP; n = 22). RESULTS Under placebo conditions, there was significantly greater engagement of the left hippocampus (p < 0.001) in the TP group compared with the NP group during verbal encoding, which survived leave-one-out analysis. The level of hippocampal activation was directly correlated (Spearman's ρ = 0.44, p = 0.008) with the severity of transient psychotic symptoms induced by THC. This difference was not present when we compared two subgroups from the same sample that were defined by sensitivity to anxiogenic effects of THC. CONCLUSIONS These results suggest that altered hippocampal activation during verbal encoding may serve as a marker of sensitivity to the acute psychotomimetic effects of THC.
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Affiliation(s)
- Sagnik Bhattacharyya
- Department of Psychosis Studies,King's College London, Institute of Psychiatry,De Crespigny Park, London, SE5 8AF,UK
| | - Thomas Sainsbury
- Department of Psychosis Studies,King's College London, Institute of Psychiatry,De Crespigny Park, London, SE5 8AF,UK
| | - Paul Allen
- Department of Psychology,University of Roehampton,UK
| | - Chiara Nosarti
- Department of Psychosis Studies,King's College London, Institute of Psychiatry,De Crespigny Park, London, SE5 8AF,UK
| | - Zerrin Atakan
- Department of Psychosis Studies,King's College London, Institute of Psychiatry,De Crespigny Park, London, SE5 8AF,UK
| | - Vincent Giampietro
- Department of Neuroimaging,King's College London, Institute of Psychiatry,PO Box 089, De Crespigny Park, London, SE5 8AF,UK
| | - Michael Brammer
- Department of Neuroimaging,King's College London, Institute of Psychiatry,PO Box 089, De Crespigny Park, London, SE5 8AF,UK
| | - P K McGuire
- Department of Psychosis Studies,King's College London, Institute of Psychiatry,De Crespigny Park, London, SE5 8AF,UK
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Bloomfield MAP, Hindocha C, Green SF, Wall MB, Lees R, Petrilli K, Costello H, Ogunbiyi MO, Bossong MG, Freeman TP. The neuropsychopharmacology of cannabis: A review of human imaging studies. Pharmacol Ther 2018; 195:132-161. [PMID: 30347211 PMCID: PMC6416743 DOI: 10.1016/j.pharmthera.2018.10.006] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The laws governing cannabis are evolving worldwide and associated with changing patterns of use. The main psychoactive drug in cannabis is Δ9-tetrahydrocannabinol (THC), a partial agonist at the endocannabinoid CB1 receptor. Acutely, cannabis and THC produce a range of effects on several neurocognitive and pharmacological systems. These include effects on executive, emotional, reward and memory processing via direct interactions with the endocannabinoid system and indirect effects on the glutamatergic, GABAergic and dopaminergic systems. Cannabidiol, a non-intoxicating cannabinoid found in some forms of cannabis, may offset some of these acute effects. Heavy repeated cannabis use, particularly during adolescence, has been associated with adverse effects on these systems, which increase the risk of mental illnesses including addiction and psychosis. Here, we provide a comprehensive state of the art review on the acute and chronic neuropsychopharmacology of cannabis by synthesizing the available neuroimaging research in humans. We describe the effects of drug exposure during development, implications for understanding psychosis and cannabis use disorder, and methodological considerations. Greater understanding of the precise mechanisms underlying the effects of cannabis may also give rise to new treatment targets.
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Affiliation(s)
- Michael A P Bloomfield
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom; Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, Faculty of Brain Sciences, University College London, United Kingdom; Psychiatric Imaging Group, MRC London Institute of Medical Sciences, Hammersmith Hospital, London, United Kingdom; NIHR University College London Hospitals Biomedical Research Centre, University College Hospital, London, United Kingdom; Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, United Kingdom.
| | - Chandni Hindocha
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom; Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, Faculty of Brain Sciences, University College London, United Kingdom; NIHR University College London Hospitals Biomedical Research Centre, University College Hospital, London, United Kingdom
| | - Sebastian F Green
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom
| | - Matthew B Wall
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, Faculty of Brain Sciences, University College London, United Kingdom; Centre for Neuropsychopharmacology, Division of Brain Sciences, Faculty of Medicine, Imperial College London, United Kingdom; Invicro UK, Hammersmith Hospital, London, United Kingdom
| | - Rachel Lees
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom; Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, Faculty of Brain Sciences, University College London, United Kingdom; Institute of Cognitive Neuroscience, Faculty of Brain Sciences, University College London, United Kingdom
| | - Katherine Petrilli
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom; Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, Faculty of Brain Sciences, University College London, United Kingdom; Institute of Cognitive Neuroscience, Faculty of Brain Sciences, University College London, United Kingdom
| | - Harry Costello
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom
| | - M Olabisi Ogunbiyi
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom
| | - Matthijs G Bossong
- Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, the Netherlands
| | - Tom P Freeman
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom; Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, Faculty of Brain Sciences, University College London, United Kingdom; Department of Psychology, University of Bath, United Kingdom; National Addiction Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, United Kingdom
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22
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Abstract
Introduction: The left and right cerebral hemispheres are not equivalent in performance of cognitive functions associated with risk factors of drug abuse, nor is their development equivalently affected by drugs of abuse. The question addressed here is whether drugs of abuse affect cognitive function as assessed by brain activation, in particular related to impulsivity, and/or whether weaker brain activation associated with impulsivity increases the risk of drug abuse. Methodology: Using PubMed and key words, articles were selected that addressed brain activation in individuals who used or abused one of the psychoactive drugs. Findings are summarized. Results: For each of the drugs, hypoactivation was found. In some cases this reduced activation was reported predominantly for the right or both hemispheres. There were fewer reports for the left hemisphere. Discussion and Conclusion: Rarely do authors focus on why only one or the other hemisphere is affected or why specific structures are affected. Neurobiological differences between the hemispheres and among various brain structures could provide clues to the specific effect of drugs. Increased attention to this gap in research will give additional insights into the etiology of drug abuse and provide direction for treatment.
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Affiliation(s)
- Harold W Gordon
- Epidemiology Research Branch, Division of Epidemiology, Services, and Prevention Research (DESPR), National Institute on Drug Abuse, USA
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23
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Scott JC, Slomiak ST, Jones JD, Rosen AFG, Moore TM, Gur RC. Association of Cannabis With Cognitive Functioning in Adolescents and Young Adults: A Systematic Review and Meta-analysis. JAMA Psychiatry 2018; 75:585-595. [PMID: 29710074 PMCID: PMC6137521 DOI: 10.1001/jamapsychiatry.2018.0335] [Citation(s) in RCA: 226] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
IMPORTANCE Substantial shifts in perception and policy regarding cannabis have recently occurred, with use of cannabis increasing while its perceived harm decreases. One possible risk of increased cannabis use is poorer cognitive functioning, especially in youth. OBJECTIVE To provide the first quantitative synthesis of the literature examining cannabis and cognitive functioning in adolescents and young adults (with a mean age of 26 years and younger). DATA SOURCES PubMed, PsycInfo, Academic Search Premier, Scopus, and bibliographies of relevant reviews were searched for peer-reviewed, English-language studies from the date the databases began through May 2017. STUDY SELECTION Consensus criteria were used to determine study inclusion through abstract and manuscript review. DATA EXTRACTION AND SYNTHESIS This study followed Meta-analysis of Observational Studies in Epidemiology guidelines. Effect size estimates were calculated using multivariate mixed-effects models for cognitive functioning outcomes classified into 10 domains. MAIN OUTCOMES AND MEASURES Results from neurocognitive tests administered in cross-sectional studies were primary outcomes, and we examined the influence of a priori explanatory variables on variability in effect size. RESULTS Sixty-nine studies of 2152 cannabis users (mean [SD] age, 20.6 [2.8] years; 1472 [68.4%] male) and 6575 comparison participants with minimal cannabis exposure were included (mean [SD] age, 20.8 [3.4]; 3669 [55.8%] male). Results indicated a small overall effect size (presented as mean d) for reduced cognitive functioning associated with frequent or heavy cannabis use (d, -0.25; 95% CI, -0.32 to -0.17; P < .001). The magnitude of effect sizes did not vary by sample age or age at cannabis use onset. However, studies requiring an abstinence period longer than 72 hours (15 studies; n = 928) had an overall effect size (d, -0.08; 95% CI, -0.22 to 0.07) that was not significantly different from 0 and smaller than studies with less stringent abstinence criteria (54 studies; n = 7799; d, -0.30; 95% CI, -0.37 to -0.22; P = .01). CONCLUSIONS AND RELEVANCE Associations between cannabis use and cognitive functioning in cross-sectional studies of adolescents and young adults are small and may be of questionable clinical importance for most individuals. Furthermore, abstinence of longer than 72 hours diminishes cognitive deficits associated with cannabis use. Although other outcomes (eg, psychosis) were not examined in the included studies, results indicate that previous studies of cannabis in youth may have overstated the magnitude and persistence of cognitive deficits associated with use. Reported deficits may reflect residual effects from acute use or withdrawal. Future studies should examine individual differences in susceptibility to cannabis-associated cognitive dysfunction.
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Affiliation(s)
- J. Cobb Scott
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia,Veterans Integrated Service Network 4 Mental Illness Research, Education, and Clinical Center at the Philadelphia VA Medical Center, Philadelphia, Pennsylvania
| | - Samantha T. Slomiak
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Jason D. Jones
- Department of Child and Adolescent Psychiatry and Behavioral Sciences, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Adon F. G. Rosen
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Tyler M. Moore
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Ruben C. Gur
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia,Veterans Integrated Service Network 4 Mental Illness Research, Education, and Clinical Center at the Philadelphia VA Medical Center, Philadelphia, Pennsylvania
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Colizzi M, Bhattacharyya S. Neurocognitive effects of cannabis: Lessons learned from human experimental studies. Progress in Brain Research 2018; 242:179-216. [DOI: 10.1016/bs.pbr.2018.08.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Ruggiero RN, Rossignoli MT, De Ross JB, Hallak JEC, Leite JP, Bueno-Junior LS. Cannabinoids and Vanilloids in Schizophrenia: Neurophysiological Evidence and Directions for Basic Research. Front Pharmacol 2017; 8:399. [PMID: 28680405 PMCID: PMC5478733 DOI: 10.3389/fphar.2017.00399] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 06/06/2017] [Indexed: 01/14/2023] Open
Abstract
Much of our knowledge of the endocannabinoid system in schizophrenia comes from behavioral measures in rodents, like prepulse inhibition of the acoustic startle and open-field locomotion, which are commonly used along with neurochemical approaches or drug challenge designs. Such methods continue to map fundamental mechanisms of sensorimotor gating, hyperlocomotion, social interaction, and underlying monoaminergic, glutamatergic, and GABAergic disturbances. These strategies will require, however, a greater use of neurophysiological tools to better inform clinical research. In this sense, electrophysiology and viral vector-based circuit dissection, like optogenetics, can further elucidate how exogenous cannabinoids worsen (e.g., tetrahydrocannabinol, THC) or ameliorate (e.g., cannabidiol, CBD) schizophrenia symptoms, like hallucinations, delusions, and cognitive deficits. Also, recent studies point to a complex endocannabinoid-endovanilloid interplay, including the influence of anandamide (endogenous CB1 and TRPV1 agonist) on cognitive variables, such as aversive memory extinction. In fact, growing interest has been devoted to TRPV1 receptors as promising therapeutic targets. Here, these issues are reviewed with an emphasis on the neurophysiological evidence. First, we contextualize imaging and electrographic findings in humans. Then, we present a comprehensive review on rodent electrophysiology. Finally, we discuss how basic research will benefit from further combining psychopharmacological and neurophysiological tools.
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Affiliation(s)
- Rafael N Ruggiero
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, Brazil
| | - Matheus T Rossignoli
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, Brazil
| | - Jana B De Ross
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, Brazil
| | - Jaime E C Hallak
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, Brazil.,National Institute for Science and Technology-Translational Medicine, National Council for Scientific and Technological Development (CNPq)Ribeirão Preto, Brazil
| | - Joao P Leite
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, Brazil
| | - Lezio S Bueno-Junior
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, Brazil
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Murray RM, Englund A, Abi-Dargham A, Lewis DA, Di Forti M, Davies C, Sherif M, McGuire P, D'Souza DC. Cannabis-associated psychosis: Neural substrate and clinical impact. Neuropharmacology 2017. [PMID: 28634109 DOI: 10.1016/j.neuropharm.2017.06.018] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Prospective epidemiological studies have consistently demonstrated that cannabis use is associated with an increased subsequent risk of both psychotic symptoms and schizophrenia-like psychoses. Early onset of use, daily use of high-potency cannabis, and synthetic cannabinoids carry the greatest risk. The risk-increasing effects are not explained by shared genetic predisposition between schizophrenia and cannabis use. Experimental studies in healthy humans show that cannabis and its active ingredient, delta-9-tetrahydrocannabinol (THC), can produce transient, dose-dependent, psychotic symptoms, as well as an array of psychosis-relevant behavioral, cognitive and psychophysiological effects; the psychotogenic effects can be ameliorated by cannabidiol (CBD). Findings from structural imaging studies in cannabis users have been inconsistent but functional MRI studies have linked the psychotomimetic and cognitive effects of THC to activation in brain regions implicated in psychosis. Human PET studies have shown that acute administration of THC weakly releases dopamine in the striatum but that chronic users are characterised by low striatal dopamine. We are beginning to understand how cannabis use impacts on the endocannabinoid system but there is much still to learn about the biological mechanisms underlying how cannabis increases risk of psychosis. This article is part of the Special Issue entitled "A New Dawn in Cannabinoid Neurobiology".
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Affiliation(s)
- R M Murray
- Institute of Psychiatry, Psychology, and Neuroscience, King's College, London, UK.
| | - A Englund
- Institute of Psychiatry, Psychology, and Neuroscience, King's College, London, UK
| | - A Abi-Dargham
- Department of Psychiatry, School of Medicine, Stony Brook University, New York, USA
| | - D A Lewis
- Department of Psychiatry, University of Pittsburg, PA, USA
| | - M Di Forti
- Institute of Psychiatry, Psychology, and Neuroscience, King's College, London, UK
| | - C Davies
- Institute of Psychiatry, Psychology, and Neuroscience, King's College, London, UK
| | - M Sherif
- Department of Psychiatry, Yale University School of Medicine, CT, USA
| | - P McGuire
- Institute of Psychiatry, Psychology, and Neuroscience, King's College, London, UK
| | - D C D'Souza
- Department of Psychiatry, Yale University School of Medicine, CT, USA
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Schmidt A, Müller F, Dolder PC, Schmid Y, Zanchi D, Liechti ME, Borgwardt S. Comparative Effects of Methylphenidate, Modafinil, and MDMA on Response Inhibition Neural Networks in Healthy Subjects. Int J Neuropsychopharmacol 2017; 20:712-720. [PMID: 28525569 PMCID: PMC5581485 DOI: 10.1093/ijnp/pyx037] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 05/16/2017] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Psychostimulants such as methylphenidate and modafinil are increasingly used by healthy people for cognitive enhancement purposes, whereas the acute effect of 3,4-methylenedioxymethamphetamine (ecstasy) on cognitive functioning in healthy subjects remains unclear. This study directly compared the acute effects of methylphenidate, modafinil, and 3,4-methylenedioxymethamphetamine on the neural mechanisms underlying response inhibition in healthy subjects. METHODS Using a double-blind, within-subject, placebo-controlled, cross-over design, methylphenidate, modafinil, and 3,4-methylenedioxymethamphetamine were administrated to 21 healthy subjects while performing a go/no-go event-related functional magnetic resonance imaging task to assess brain activation during motor response inhibition. RESULTS Relative to placebo, methylphenidate and modafinil but not 3,4-methylenedioxymethamphetamine improved inhibitory performance. Methylphenidate significantly increased activation in the right middle frontal gyrus, middle/superior temporal gyrus, inferior parietal lobule, presupplementary motor area, and anterior cingulate cortex compared with placebo. Methylphenidate also induced significantly higher activation in the anterior cingulate cortex and presupplementary motor area and relative to modafinil. Relative to placebo, modafinil significantly increased activation in the right middle frontal gyrus and superior/inferior parietal lobule, while 3,4-methylenedioxymethamphetamine significantly increased activation in the right middle/inferior frontal gyrus and superior parietal lobule. CONCLUSIONS Direct comparison of methylphenidate, modafinil, and 3,4-methylenedioxymethamphetamine revealed broad recruitment of fronto-parietal regions but specific effects of methylphenidate on middle/superior temporal gyrus, anterior cingulate cortex, and presupplementary motor area activation, suggesting dissociable modulations of response inhibition networks and potentially the superiority of methylphenidate in the enhancement of cognitive performance in healthy subjects.
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Affiliation(s)
- André Schmidt
- Department of Psychiatry (UPK), University of Basel, Basel, Switzerland (Dr Schmidt, Dr Müller, Mr Zanchi, and Dr Borgwardt); Division of Clinical Pharmacology and Toxicology, University of Basel and Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland (Mr Dolder, Dr Schmid, and Dr Liechti).,Correspondence: André Schmidt, PhD, University of Basel, Department of Psychiatry (UPK), Wilhelm Klein Strasse 27, 4012 Basel, Switzerland ()
| | - Felix Müller
- Department of Psychiatry (UPK), University of Basel, Basel, Switzerland (Dr Schmidt, Dr Müller, Mr Zanchi, and Dr Borgwardt); Division of Clinical Pharmacology and Toxicology, University of Basel and Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland (Mr Dolder, Dr Schmid, and Dr Liechti)
| | - Patrick C Dolder
- Department of Psychiatry (UPK), University of Basel, Basel, Switzerland (Dr Schmidt, Dr Müller, Mr Zanchi, and Dr Borgwardt); Division of Clinical Pharmacology and Toxicology, University of Basel and Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland (Mr Dolder, Dr Schmid, and Dr Liechti)
| | - Yasmin Schmid
- Department of Psychiatry (UPK), University of Basel, Basel, Switzerland (Dr Schmidt, Dr Müller, Mr Zanchi, and Dr Borgwardt); Division of Clinical Pharmacology and Toxicology, University of Basel and Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland (Mr Dolder, Dr Schmid, and Dr Liechti)
| | - Davide Zanchi
- Department of Psychiatry (UPK), University of Basel, Basel, Switzerland (Dr Schmidt, Dr Müller, Mr Zanchi, and Dr Borgwardt); Division of Clinical Pharmacology and Toxicology, University of Basel and Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland (Mr Dolder, Dr Schmid, and Dr Liechti)
| | - Matthias E Liechti
- Department of Psychiatry (UPK), University of Basel, Basel, Switzerland (Dr Schmidt, Dr Müller, Mr Zanchi, and Dr Borgwardt); Division of Clinical Pharmacology and Toxicology, University of Basel and Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland (Mr Dolder, Dr Schmid, and Dr Liechti)
| | - Stefan Borgwardt
- Department of Psychiatry (UPK), University of Basel, Basel, Switzerland (Dr Schmidt, Dr Müller, Mr Zanchi, and Dr Borgwardt); Division of Clinical Pharmacology and Toxicology, University of Basel and Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland (Mr Dolder, Dr Schmid, and Dr Liechti)
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Allendorfer JB, Szaflarski JP. Neuroimaging studies towards understanding the central effects of pharmacological cannabis products on patients with epilepsy. Epilepsy Behav 2017; 70:349-354. [PMID: 28109780 DOI: 10.1016/j.yebeh.2016.11.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 11/11/2016] [Accepted: 11/14/2016] [Indexed: 02/04/2023]
Abstract
Recent interest for the use of cannabis-derived products as therapeutic agents in the treatment of epilepsies has necessitated a reevaluation of their effects on brain and behavior. Overall, prolonged cannabis use is thought to result in functional and structural brain alterations. These effects may be dependent on a number of factors: e.g., which phytocannabinoid is used (e.g., cannabidiol (CBD) vs. tetrahyrocannabinol (THC)), the frequency of use (occasional vs. heavy), and at what age (prenatal, childhood, adulthood) the use began. However, due to the fact that there are over seven hundred constituents that make up the Cannabis sativa plant, it is difficult to determine which compound or combination of compounds is responsible for specific effects when studying recreational users. Therefore, this review focuses only on the functional MRI studies investigating the effects of specific pharmacological preparations of cannabis compounds, specifically THC, tetrahydrocannabivarin (THCV), and CBD, on brain function in healthy individuals and persons with epilepsy with references to non-epilepsy studies only to underline the gaps in research that need to be filled before cannabis-derived products are considered for a wide use in the treatment of epilepsy. This article is part of a Special Issue entitled "Cannabinoids and Epilepsy".
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Affiliation(s)
- Jane B Allendorfer
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Jerzy P Szaflarski
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
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Barkus E, Morrison P, Di Forti M, Murray RM. Are deficits in cognition associated with psychotic-like experiences after cannabis? Hum Psychopharmacol 2016; 31:402-411. [PMID: 27859664 DOI: 10.1002/hup.2556] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 07/07/2016] [Accepted: 09/02/2016] [Indexed: 12/13/2022]
Abstract
UNLABELLED Not all individuals who smoke cannabis report psychotic-like experiences. Given that risk factors for psychotic disorders are multifaceted, precipitating factors to psychotic-like experiences after cannabis are likely to be equally complex. Reduced neurocognitive performance is associated with both psychosis risk and cannabis use. Therefore, it is possible cognitive performance may differentiate those who report psychotic-like experiences after cannabis from those who do not. We determined whether those reporting psychotic/dysphoric experiences after cannabis had reduced neurocognitive performance compared to those reporting primarily euphoric experiences. METHODS Participants were recruited on the basis of responses to the cannabis high captured by the Psychosis-Dysphoric and Euphoric experiences subscales from the Cannabis Experiences Questionnaire (CEQ). RESULTS Compared to participants reporting primarily euphoric cannabis experiences (n = 36; 44% male; mean age (SD) = 28 (9) years), those who reported psychotic/dysphoric experiences (n = 40; 45% male; mean age (SD) = 26 (5) years) demonstrated significantly faster responses to a trial and error learning task. In the presence of distracters, those with psychotic/dysphoric experiences after cannabis made more errors on a Continuous Performance Task. CONCLUSIONS Those who report psychotic/dysphoric experiences after cannabis have subtle inefficiencies in their cognitive processes. The multiple factors which predict vulnerability to psychotic-like experiences after cannabis require further investigation.
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Affiliation(s)
- Emma Barkus
- School of Psychology, University of Wollongong, Wollongong, New South Wales, Australia
| | - Paul Morrison
- Institute of Psychiatry, Psychology & Neuroscience, London, UK
| | - Marta Di Forti
- Institute of Psychiatry, Psychology & Neuroscience, London, UK
| | - Robin M Murray
- Institute of Psychiatry, Psychology & Neuroscience, London, UK
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Spronk DB, De Bruijn ERA, van Wel JHP, Ramaekers JG, Verkes RJ. Acute effects of cocaine and cannabis on response inhibition in humans: an ERP investigation. Addict Biol 2016; 21:1186-1198. [PMID: 26037156 DOI: 10.1111/adb.12274] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Substance abuse has often been associated with alterations in response inhibition in humans. Not much research has examined how the acute effects of drugs modify the neurophysiological correlates of response inhibition, or how these effects interact with individual variation in trait levels of impulsivity and novelty seeking. This study investigated the effects of cocaine and cannabis on behavioural and event-related potential (ERP) correlates of response inhibition in 38 healthy drug using volunteers. A double-blind placebo-controlled randomized three-way crossover design was used. All subjects completed a standard Go/NoGo task after administration of the drugs. Compared with a placebo, cocaine yielded improved accuracy, quicker reaction times and an increased prefrontal NoGo-P3 ERP. Cannabis produced opposing results; slower reaction times, impaired accuracy and a reduction in the amplitude of the prefrontal NoGo-P3. Cannabis in addition decreased the amplitude of the parietally recorded P3, while cocaine did not affect this. Neither drugs specifically affected the N2 component, suggesting that pre-motor response inhibitory processes remain unaffected. Neither trait impulsivity nor novelty seeking interacted with drug-induced effects on measures of response inhibition. We conclude that acute drug effects on response inhibition seem to be specific to the later, evaluative stages of response inhibition. The acute effects of cannabis appeared less specific to response inhibition than those of cocaine. Together, the results show that the behavioural effects on response inhibition are reflected in electrophysiological correlates. This study did not support a substantial role of vulnerability personality traits in the acute intoxication stage.
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Affiliation(s)
- Desirée B. Spronk
- Department of Psychiatry; Radboud University Medical Centre; Nijmegen The Netherlands
- Donders Institute for Brain, Cognition and Behaviour; Radboud University Nijmegen; Nijmegen The Netherlands
| | - Ellen R. A. De Bruijn
- Department of Clinical Psychology, Leiden Institute for Brain and Cognition; Leiden University; Leiden The Netherlands
| | - Janelle H. P. van Wel
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience; Maastricht University; Maastricht The Netherlands
| | - Johannes G. Ramaekers
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience; Maastricht University; Maastricht The Netherlands
| | - Robbert J. Verkes
- Department of Psychiatry; Radboud University Medical Centre; Nijmegen The Netherlands
- Donders Institute for Brain, Cognition and Behaviour; Radboud University Nijmegen; Nijmegen The Netherlands
- Pompestichting for Forensic Psychiatry; Nijmegen The Netherlands
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Sherif M, Radhakrishnan R, D'Souza DC, Ranganathan M. Human Laboratory Studies on Cannabinoids and Psychosis. Biol Psychiatry 2016; 79:526-38. [PMID: 26970363 DOI: 10.1016/j.biopsych.2016.01.011] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 01/14/2016] [Accepted: 01/14/2016] [Indexed: 10/22/2022]
Abstract
Some of the most compelling evidence supporting an association between cannabinoid agonists and psychosis comes from controlled laboratory studies in humans. Randomized, double-blind, placebo-controlled, crossover laboratory studies demonstrate that cannabinoid agonists, including phytocannabinoids and synthetic cannabinoids, produce a wide range of positive, negative, and cognitive symptoms and psychophysiologic deficits in healthy human subjects that resemble the phenomenology of schizophrenia. These effects are time locked to drug administration, are dose related, and are transient and rarely necessitate intervention. The magnitude of effects is similar to the effects of ketamine but qualitatively distinct from other psychotomimetic drugs, including ketamine, amphetamine, and salvinorin A. Cannabinoid agonists have also been shown to transiently exacerbate symptoms in individuals with schizophrenia in laboratory studies. Patients with schizophrenia are more vulnerable than healthy control subjects to the acute behavioral and cognitive effects of cannabinoid agonists and experience transient exacerbation of symptoms despite treatment with antipsychotic medications. Furthermore, laboratory studies have failed to demonstrate any "beneficial" effects of cannabinoid agonists in individuals with schizophrenia-challenging the cannabis self-medication hypothesis. Emerging evidence suggests that polymorphisms of several genes related to dopamine metabolism (e.g., COMT, DAT1, and AKT1) may moderate the effects of cannabinoid agonists in laboratory studies. Cannabinoid agonists induce dopamine release, although the magnitude of release does not appear to be commensurate to the magnitude and spectrum of their acute psychotomimetic effects. Interactions between the endocannabinoid, gamma-aminobutyric acid, and glutamate systems and their individual and interactive effects on neural oscillations provide a plausible mechanism underlying the psychotomimetic effects of cannabinoids.
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Affiliation(s)
- Mohamed Sherif
- Schizophrenia and Neuropharmacology Research Group, VA Connecticut Healthcare System, West Haven; Abraham Ribicoff Research Facilities, Connecticut Mental Health Center, New Haven, Connecticut; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| | - Rajiv Radhakrishnan
- Schizophrenia and Neuropharmacology Research Group, VA Connecticut Healthcare System, West Haven; Abraham Ribicoff Research Facilities, Connecticut Mental Health Center, New Haven, Connecticut; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| | - Deepak Cyril D'Souza
- Schizophrenia and Neuropharmacology Research Group, VA Connecticut Healthcare System, West Haven; Abraham Ribicoff Research Facilities, Connecticut Mental Health Center, New Haven, Connecticut; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| | - Mohini Ranganathan
- Schizophrenia and Neuropharmacology Research Group, VA Connecticut Healthcare System, West Haven; Abraham Ribicoff Research Facilities, Connecticut Mental Health Center, New Haven, Connecticut; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut.
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Abstract
Answer questions and earn CME/CNE Marijuana has been used for centuries, and interest in its medicinal properties has been increasing in recent years. Investigations into these medicinal properties has led to the development of cannabinoid pharmaceuticals such as dronabinol, nabilone, and nabiximols. Dronabinol is best studied in the treatment of nausea secondary to cancer chemotherapy and anorexia associated with weight loss in patients with acquired immune deficiency syndrome, and is approved by the US Food and Drug Administration for those indications. Nabilone has been best studied for the treatment of nausea secondary to cancer chemotherapy. There are also limited studies of these drugs for other conditions. Nabiximols is only available in the United States through clinical trials, but is used in Canada and the United Kingdom for the treatment of spasticity secondary to multiple sclerosis and pain. Studies of marijuana have concentrated on nausea, appetite, and pain. This article will review the literature regarding the medical use of marijuana and these cannabinoid pharmaceuticals (with emphasis on indications relevant to oncology), as well as available information regarding adverse effects of marijuana use.
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Affiliation(s)
- Joan L Kramer
- Medical Editor, American Cancer Society, Atlanta, GA
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Wrege J, Schmidt A, Walter A, Smieskova R, Bendfeldt K, Radue EW, Lang UE, Borgwardt S. Effects of cannabis on impulsivity: a systematic review of neuroimaging findings. Curr Pharm Des 2015; 20:2126-37. [PMID: 23829358 PMCID: PMC4052819 DOI: 10.2174/13816128113199990428] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 06/10/2013] [Indexed: 01/18/2023]
Abstract
We conducted a systematic review to assess the evidence for specific effects of cannabis on impulsivity, disinhibition and motor
control. The review had a specific focus on neuroimaging findings associated with acute and chronic use of the drug and covers literature
published up until May 2012. Seventeen studies were identified, of which 13 met the inclusion criteria; three studies investigated
acute effects of cannabis (1 fMRI, 2 PET), while six studies investigated non-acute functional effects (4 fMRI, 2 PET), and four studies
investigated structural alterations. Functional imaging studies of impulsivity studies suggest that prefrontal blood flow is lower in chronic
cannabis users than in controls. Studies of acute administration of THC or marijuana report increased brain metabolism in several brain
regions during impulsivity tasks. Structural imaging studies of cannabis users found differences in reduced prefrontal volumes and white
matter integrity that might mediate the abnormal impulsivity and mood observed in marijuana users. To address the question whether impulsivity
as a trait precedes cannabis consumption or whether cannabis aggravates impulsivity and discontinuation of usage more longitudinal
study designs are warranted.
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Affiliation(s)
| | | | | | | | | | | | | | - Stefan Borgwardt
- Department of Psychiatry UPK, University of Basel, Petersgraben 4, 4031 Basel, Switzerland.
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Løberg EM, Helle S, Nygård M, Berle JØ, Kroken RA, Johnsen E. The Cannabis Pathway to Non-Affective Psychosis may Reflect Less Neurobiological Vulnerability. Front Psychiatry 2014; 5:159. [PMID: 25477825 PMCID: PMC4235385 DOI: 10.3389/fpsyt.2014.00159] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 10/24/2014] [Indexed: 12/19/2022] Open
Abstract
There is a high prevalence of cannabis use reported in non-affective psychosis. Early prospective longitudinal studies conclude that cannabis use is a risk factor for psychosis, and neurochemical studies on cannabis have suggested potential mechanisms for this effect. Recent advances in the field of neuroscience and genetics may have important implications for our understanding of this relationship. Importantly, we need to better understand the vulnerability × cannabis interaction to shed light on the mediators of cannabis as a risk factor for psychosis. Thus, the present study reviews recent literature on several variables relevant for understanding the relationship between cannabis and psychosis, including age of onset, cognition, brain functioning, family history, genetics, and neurological soft signs (NSS) in non-affective psychosis. Compared with non-using non-affective psychosis, the present review shows that there seem to be fewer stable cognitive deficits in patients with cannabis use and psychosis, in addition to fewer NSS and possibly more normalized brain functioning, indicating less neurobiological vulnerability for psychosis. There are, however, some familiar and genetic vulnerabilities present in the cannabis psychosis group, which may influence the cannabis pathway to psychosis by increasing sensitivity to cannabis. Furthermore, an earlier age of onset suggests a different pathway to psychosis in the cannabis-using patients. Two alternative vulnerability models are presented to integrate these seemingly paradoxical findings.
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Affiliation(s)
- Else-Marie Løberg
- Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Psychology, University of Bergen, Bergen, Norway
| | - Siri Helle
- Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
| | - Merethe Nygård
- Laboratory of Clinical Biochemistry, Haukeland University Hospital, Bergen, Norway
| | - Jan Øystein Berle
- Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
| | - Rune A. Kroken
- Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
| | - Erik Johnsen
- Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
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Bossong MG, Jansma JM, Bhattacharyya S, Ramsey NF. Role of the endocannabinoid system in brain functions relevant for schizophrenia: an overview of human challenge studies with cannabis or ∆9-tetrahydrocannabinol (THC). Prog Neuropsychopharmacol Biol Psychiatry 2014; 52:53-69. [PMID: 24380726 DOI: 10.1016/j.pnpbp.2013.11.017] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Revised: 10/16/2013] [Accepted: 11/25/2013] [Indexed: 12/30/2022]
Abstract
Accumulating evidence suggests involvement of the endocannabinoid system in the pathophysiology of schizophrenia, which signifies a potential application for this system in the treatment of this disorder. However, before new research can focus on potential treatments that work by manipulating the endocannabinoid system, it needs to be elucidated how this system is involved in symptoms of schizophrenia. Here we review human studies that investigated acute effects of cannabis or ∆9-tetrahydrocannabinol (THC) on brain functions that are implicated in schizophrenia. Results suggest that the impact of THC administration depends on the difficulty of the task performed. Impaired performance of cognitive paradigms is reported on more challenging tasks, which is associated with both activity deficits in temporal and prefrontal areas and a failure to deactivate regions of the default mode network. Comparable reductions in prefrontal activity and impairments in deactivation of the default mode network are seen in patients during performance of cognitive paradigms. Normal performance levels after THC administration demonstrated for less demanding tasks are shown to be related to either increased neural effort in task-specific regions ('neurophysiological inefficiency'), or recruitment of alternative brain areas, which suggests a change in strategy to meet cognitive demands. Particularly a pattern of performance and brain activity corresponding with an inefficient working memory system is consistently demonstrated in patients. These similarities in brain function between intoxicated healthy volunteers and schizophrenia patients provide an argument for a role of the endocannabinoid system in symptoms of schizophrenia, and further emphasize this system as a potential novel target for treatment of these symptoms.
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Affiliation(s)
- Matthijs G Bossong
- Institute of Psychiatry, Department of Psychosis Studies, King's College London, 16 De Crespigny Park, London SE5 8AF, United Kingdom.
| | - J Martijn Jansma
- Rudolf Magnus Institute of Neuroscience, Department of Neurology and Neurosurgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - Sagnik Bhattacharyya
- Institute of Psychiatry, Department of Psychosis Studies, King's College London, 16 De Crespigny Park, London SE5 8AF, United Kingdom
| | - Nick F Ramsey
- Rudolf Magnus Institute of Neuroscience, Department of Neurology and Neurosurgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
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Kleinloog D, Roozen F, De Winter W, Freijer J, Van Gerven J. Profiling the subjective effects of Δ⁹-tetrahydrocannabinol using visual analogue scales. Int J Methods Psychiatr Res 2014; 23:245-56. [PMID: 24496889 PMCID: PMC6878449 DOI: 10.1002/mpr.1424] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 05/14/2013] [Accepted: 05/15/2013] [Indexed: 11/07/2022] Open
Abstract
The subjective effects of cannabis and its main psychoactive component Δ(9) -tetrahydrocannabinol (THC) have played an important part in determining the therapeutic potential of cannabinoid agonists and antagonists. The effects mainly consist of feeling high, changes in perception, feelings of relaxation and occasionally dysphoric reactions. These effects are captured by two of the most frequently used visual analogue scales (VASs) in clinical (pharmacologic) research to measure subjective effects: VAS Bond and Lader (alertness, calmness and mood) and VAS Bowdle (psychedelic effects). In this analysis, the effects of THC on these VASs were compared within a total of 217 subjects who participated in 10 different studies. Not surprisingly, the item feeling high was found to be the best predictor for the effect of THC. Three separate clusters that describe the spectrum of subjective effects of THC were identified using different statistical methods, consisting of VAS "time", "thoughts" and "high" ("perception"), VAS "drowsy", "muzzy", "mentally slow" and "dreamy" ("relaxation") and VAS "voices", "meaning" and "suspicious" ("dysphoria"). These results provide experimental evidence that THC can evoke different classes of effects. These distinct subjective clusters could represent effects on various systems in the brain, which can be used to further differentiate the involvement of endocannabinoid systems in health and disease.
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Abstract
The link between cannabis use and psychosis comprises three distinct relationships: acute psychosis associated with cannabis intoxication, acute psychosis that lasts beyond the period of acute intoxication, and persistent psychosis not time-locked to exposure. Experimental studies reveal that cannabis, tetrahydrocannabinol (THC) and synthetic cannabinoids reliably produce transient positive, negative, and cognitive symptoms in healthy volunteers. Case-studies indicate that cannabinoids can induce acute psychosis which lasts beyond the period of acute intoxication but resolves within a month. Exposure to cannabis in adolescence is associated with a risk for later psychotic disorder in adulthood; this association is consistent, temporally related, shows a dose-response, and is biologically plausible. However, cannabis is neither necessary nor sufficient to cause a persistent psychotic disorder. More likely it is a component cause that interacts with other factors to result in psychosis. The link between cannabis and psychosis is moderated by age at onset of cannabis use, childhood abuse and genetic vulnerability. While more research is needed to better characterize the relationship between cannabinoid use and the onset and persistence of psychosis, clinicians should be mindful of the potential risk of psychosis especially in vulnerable populations, including adolescents and those with a psychosis diathesis.
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Affiliation(s)
- Samuel T Wilkinson
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Rajiv Radhakrishnan
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Deepak Cyril D'Souza
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA ; Abraham Ribicoff Research Facilities, Connecticut Mental Health Center, New Haven, CT, USA ; Schizophrenia and Neuropharmacology Research Group, VA Connecticut Healthcare System, West Haven, CT, USA
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Trape S, Charles-nicolas A, Jehel L, Lacoste J. Early Cannabis Use Is Associated With Severity of Cocaine-Induced Psychosis Among Cocaine Smokers in Martinique, French West Indies. J Addict Med 2014; 8:33-9. [DOI: 10.1097/adm.0000000000000003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Serafini G, Pompili M, Innamorati M, Temple EC, Amore M, Borgwardt S, Girardi P. The Association between Cannabis Use, Mental Illness, and Suicidal Behavior: What is the Role of Hopelessness? Front Psychiatry 2013; 4:125. [PMID: 24133458 PMCID: PMC3795410 DOI: 10.3389/fpsyt.2013.00125] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 09/23/2013] [Indexed: 11/25/2022] Open
Affiliation(s)
- Gianluca Serafini
- Department of Neurosciences, Mental Health, and Sensory Organs, Sant'Andrea Hospital, Sapienza University of Rome , Rome, Italy
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