1
|
Benedetti E, Lombardi G, Molinaro S. Can drug policies modify cannabis use starting choice? Insights from criminalisation in Italy. ADVANCES IN LIFE COURSE RESEARCH 2023; 58:100566. [PMID: 38054868 DOI: 10.1016/j.alcr.2023.100566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 08/19/2023] [Accepted: 08/21/2023] [Indexed: 12/07/2023]
Abstract
A key question in the ongoing drug policy debate is whether legalising cannabis leads to an increase in cannabis use. In Europe although no country has yet moved to legalisation, many have decriminalised personal possession. However, some jurisdictions are still discussing increased sanctions or have further strengthened penalties for the possession of illicit substances in order to deter widespread cannabis use. This is the case in Italy, where a law introduced in 2006 and repealed in 2014 de facto criminalised personal drug possession, and a potential increase in penalties is currently being debated as a policy option. Despite the intense public debate surrounding the legal status of cannabis, limited empirical research has been conducted in Europe to assess the population-level effects of drug policy reforms, mainly due to data availability constraints. In this study, we analyse the effect of criminalisation on the age of onset of cannabis use using an unique dataset that combines seven waves (2001-2017) of the nationally representative Italian Population Survey on Alcohol and other Drugs with relevant socio-economic data. The final dataset comprises 77,650 observations. Leveraging the rare opportunity to examine the effects of a policy that remained in force for a limited period, our empirical investigation employs a Complementary Log-Log model to analyse the starting rate, that is, the transition rate from non-use to use. To do so, we use self-reported data on the age of first cannabis use. Our results suggest that the implementation of stricter punishments has a significant effect in reducing the likelihood of early cannabis use initiation. The observed impact of criminalisation is limited in younger ages and diminished as adulthood approaches. This paper also discusses other considerations related to the social costs of criminalisation, which should also be taken into account in the ongoing policy debate.
Collapse
Affiliation(s)
- Elisa Benedetti
- National Research Council, Institute of Clinical Physiology (CNR, IFC), via Moruzzi, 1, 56124 Pisa, Italy.
| | - Gabriele Lombardi
- Department of Statistics, Computer Science, Applications "Giuseppe Parenti" - DiSIA, University of Florence, viale Morgagni, 59, 50134 Florence, Italy.
| | - Sabrina Molinaro
- National Research Council, Institute of Clinical Physiology (CNR, IFC), via Moruzzi, 1, 56124 Pisa, Italy.
| |
Collapse
|
2
|
Skala K, Trabi T, Fuchs M, Gössler R, Haas-Stockmair CW, Kriechbaumer N, Leitner M, Ortner N, Reiter M, Müller C, Wladika W. [Cannabis use in adolescents : Narrative Review and Position paper of the "Addiction Disorders in Adolescents" task force of the Austrian Society for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy (ÖGKJP)]. NEUROPSYCHIATRIE : KLINIK, DIAGNOSTIK, THERAPIE UND REHABILITATION : ORGAN DER GESELLSCHAFT OSTERREICHISCHER NERVENARZTE UND PSYCHIATER 2023; 37:175-195. [PMID: 35900691 DOI: 10.1007/s40211-022-00424-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 07/01/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Cannabis is the illegal drug most frequently used by Minors in Austria. Due to the gradual decriminalization and legalization that has taken place in many European countries in recent years, the ÖGKJP would like to take a balanced and scientifically based stand on the complex issue of cannabis use and abuse among young people. METHODS The authors searched the medline for current studies using searches tailored to each specific subtopic. Furthermore, recognized compendiums were quoted. RESULTS While occasional recreational use of cannabis in adults with completed brain maturation and no risk profile for mental disorders is likely to be relatively harmless, early initiation of use with regular use and the increasingly available, highly potent cannabis varieties can lead to explicit and sometimes irreversible neurocognitive brain dysfunction. CONCLUSION Legalisation of cannabis consumption for minors needs to be objected to due to the risks of the expected damage in the area of brain development. At the same time, however, it is important to establish sensible legal regulations in order to be able to adequately counteract the fact that over 30% of all European young people occasionally consume cannabis. We are also clearly recommending to not criminalize cannabis users and provide necessary support to vulnerable and addicted cannabis users.
Collapse
Affiliation(s)
- Katrin Skala
- Univ. Klinik für Kinder und Jugendpsychiatrie, Medizinische Universität Wien, Währinger Gürtel 18-20, 1090, Wien, Österreich.
| | - Thomas Trabi
- Abteilung für Kinder- und Jugendpsychiatrie, LKH Graz II, Graz, Österreich
| | - Martin Fuchs
- Univ. Klinik für Kinder- und Jugendpsychiatrie, Medizinische Universität Innsbruck, Innsbruck, Österreich
| | - Ralf Gössler
- Abteilung für Kinder- und Jugendpsychiatrie, Klinik Floridsdorf, Floridsdorf, Österreich
| | | | | | - Monika Leitner
- Praxis für Kinder- und Jugendpsychiatrie, Graz, Österreich
| | - Nora Ortner
- Univ. Klinik für Kinder- und Jugendpsychiatrie, Medizinische Universität Innsbruck, Innsbruck, Österreich
| | - Melanie Reiter
- Univ. Klinik für Kinder- und Jugendpsychiatrie, Medizinische Universität Innsbruck, Innsbruck, Österreich
| | - Christian Müller
- Ambulatorium für Kinder- u. Jugendpsychiatrie, PSD Einsenstadt, Einsenstadt, Österreich
| | - Wolfgang Wladika
- Abteilung für Neurologie und Psychiatrie des Kindes- und Jugendalters, Klinikum Klagenfurt, Klagenfurt, Österreich
| |
Collapse
|
3
|
Scott JC. Impact of Adolescent Cannabis Use on Neurocognitive and Brain Development. Psychiatr Clin North Am 2023; 46:655-676. [PMID: 37879830 DOI: 10.1016/j.psc.2023.03.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
Research examining associations between frequent cannabis use in adolescence and brain-behavior outcomes has increased substantially over the past 2 decades. This review attempts to synthesize the state of evidence in this area of research while acknowledging challenges in interpretation. Although there is converging evidence that ongoing, frequent cannabis use in adolescence is associated with small reductions in cognitive functioning, there is still significant debate regarding the persistence of reductions after a period of abstinence. Similarly, there is controversy regarding the replicability of structural and functional neuroimaging findings related to frequent cannabis use in adolescence. Larger studies with informative designs are needed.
Collapse
Affiliation(s)
- J Cobb Scott
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, 3700 Hamilton Walk, 5th Floor, Philadelphia, PA 19104, USA; VISN4 Mental Illness Research, Education, and Clinical Center at the Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA 19104, USA.
| |
Collapse
|
4
|
Steinfeld MR, Torregrossa MM. Consequences of adolescent drug use. Transl Psychiatry 2023; 13:313. [PMID: 37802983 PMCID: PMC10558564 DOI: 10.1038/s41398-023-02590-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 05/22/2023] [Accepted: 08/23/2023] [Indexed: 10/08/2023] Open
Abstract
Substance use in adolescence is a known risk factor for the development of neuropsychiatric and substance use disorders in adulthood. This is in part due to the fact that critical aspects of brain development occur during adolescence, which can be altered by drug use. Despite concerted efforts to educate youth about the potential negative consequences of substance use, initiation remains common amongst adolescents world-wide. Additionally, though there has been substantial research on the topic, many questions remain about the predictors and the consequences of adolescent drug use. In the following review, we will highlight some of the most recent literature on the neurobiological and behavioral effects of adolescent drug use in rodents, non-human primates, and humans, with a specific focus on alcohol, cannabis, nicotine, and the interactions between these substances. Overall, consumption of these substances during adolescence can produce long-lasting changes across a variety of structures and networks which can have enduring effects on behavior, emotion, and cognition.
Collapse
Affiliation(s)
- Michael R Steinfeld
- Department of Psychiatry, University of Pittsburgh, 450 Technology Drive, Pittsburgh, PA, 15219, USA.
- Center for Neuroscience, University of Pittsburgh, 4200 Fifth Ave, Pittsburgh, PA, 15213, USA.
| | - Mary M Torregrossa
- Department of Psychiatry, University of Pittsburgh, 450 Technology Drive, Pittsburgh, PA, 15219, USA
- Center for Neuroscience, University of Pittsburgh, 4200 Fifth Ave, Pittsburgh, PA, 15213, USA
| |
Collapse
|
5
|
Abstract
Research examining associations between frequent cannabis use in adolescence and brain-behavior outcomes has increased substantially over the past 2 decades. This review attempts to synthesize the state of evidence in this area of research while acknowledging challenges in interpretation. Although there is converging evidence that ongoing, frequent cannabis use in adolescence is associated with small reductions in cognitive functioning, there is still significant debate regarding the persistence of reductions after a period of abstinence. Similarly, there is controversy regarding the replicability of structural and functional neuroimaging findings related to frequent cannabis use in adolescence. Larger studies with informative designs are needed.
Collapse
Affiliation(s)
- J Cobb Scott
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, 3700 Hamilton Walk, 5th Floor, Philadelphia, PA 19104, USA; VISN4 Mental Illness Research, Education, and Clinical Center at the Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA 19104, USA.
| |
Collapse
|
6
|
Dellazizzo L, Potvin S, Giguère S, Dumais A. Evidence on the acute and residual neurocognitive effects of cannabis use in adolescents and adults: a systematic meta-review of meta-analyses. Addiction 2022; 117:1857-1870. [PMID: 35048456 DOI: 10.1111/add.15764] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 11/11/2021] [Indexed: 12/18/2022]
Abstract
BACKGROUND Cannabis is among the most consumed psychoactive substances world-wide. Considering changing policy trends regarding the substance, it is crucial to understand more clearly its potential acute and residual adverse effects from a public health viewpoint. Cognitive function is one of the targeted areas with conflicting findings. This meta-review measured the magnitude of acute and residual effects of cannabis on cognition in adolescents and adults provided by meta-analyses and evaluated quality of evidence. METHODS A systematic search was performed in PubMed, PsycINFO, Web of Science and Google Scholar. Meta-analyses were included if they quantitatively examined the performances of users from the general population on cognitive tasks. RESULTS The search retrieved 10 eligible meta-analyses (71 effects sizes, n = 43 761) with evidence ranging from low to moderate quality, which were categorized into domains of cognitive functions: executive functions (k = 7), learning and memory (k = 5), attention (k = 4), processing speed (k = 5), perceptual motor function (k = 2) and language (k = 2). Verbal learning and memory displayed the most robust evidence and were most impaired by acute cannabis intoxication that persisted after intoxication passed. Small-to-moderate acute and residual adverse effects were reported for executive functioning. Cannabis use led to small deficits in inhibitory processes and flexibility, whereas small-to-moderate deficits were reported for working memory and decision-making. Evidence regarding processing speed and attention has shown that cannabis administration induced small-to-moderate adverse effects and residual neurocognitive deficits were observed in heavy cannabis-using youths. Results showed no significant difference between cannabis users and non-users on language, and small-to-moderate effects for simple motor skills. CONCLUSION Meta-analytical data on the acute effects of cannabis use on neurocognitive function have shown that cannabis intoxication leads to small to moderate deficits in several cognitive domains. These acute impairments accord with documented residual effects, suggesting that the detrimental effects of cannabis persist beyond acute intake.
Collapse
Affiliation(s)
- Laura Dellazizzo
- Research center of the Institut Universitaire en Santé Mentale de Montréal, Montreal, Canada.,Department of Psychiatry and Addictology, Faculty of Medicine, Université de Montréal, Montreal, Canada
| | - Stéphane Potvin
- Research center of the Institut Universitaire en Santé Mentale de Montréal, Montreal, Canada.,Department of Psychiatry and Addictology, Faculty of Medicine, Université de Montréal, Montreal, Canada
| | - Sabrina Giguère
- Research center of the Institut Universitaire en Santé Mentale de Montréal, Montreal, Canada.,Department of Psychiatry and Addictology, Faculty of Medicine, Université de Montréal, Montreal, Canada
| | - Alexandre Dumais
- Research center of the Institut Universitaire en Santé Mentale de Montréal, Montreal, Canada.,Department of Psychiatry and Addictology, Faculty of Medicine, Université de Montréal, Montreal, Canada.,Institut national de psychiatrie légale Philippe-Pinel, Montreal, Canada
| |
Collapse
|
7
|
Gage SH, Sallis HM, Lassi G, Wootton RE, Mokrysz C, Davey Smith G, Munafò MR. Does smoking cause lower educational attainment and general cognitive ability? Triangulation of causal evidence using multiple study designs. Psychol Med 2022; 52:1578-1586. [PMID: 33023701 PMCID: PMC9226381 DOI: 10.1017/s0033291720003402] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 08/18/2020] [Accepted: 09/03/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND Observational studies have found associations between smoking and both poorer cognitive ability and lower educational attainment; however, evaluating causality is challenging. We used two complementary methods to explore this. METHODS We conducted observational analyses of up to 12 004 participants in a cohort study (Study One) and Mendelian randomisation (MR) analyses using summary and cohort data (Study Two). Outcome measures were cognitive ability at age 15 and educational attainment at age 16 (Study One), and educational attainment and fluid intelligence (Study Two). RESULTS Study One: heaviness of smoking at age 15 was associated with lower cognitive ability at age 15 and lower educational attainment at age 16. Adjustment for potential confounders partially attenuated findings (e.g. fully adjusted cognitive ability β -0.736, 95% CI -1.238 to -0.233, p = 0.004; fully adjusted educational attainment β -1.254, 95% CI -1.597 to -0.911, p < 0.001). Study Two: MR indicated that both smoking initiation and lifetime smoking predict lower educational attainment (e.g. smoking initiation to educational attainment inverse-variance weighted MR β -0.197, 95% CI -0.223 to -0.171, p = 1.78 × 10-49). Educational attainment results were robust to sensitivity analyses, while analyses of general cognitive ability were less so. CONCLUSION We find some evidence of a causal effect of smoking on lower educational attainment, but not cognitive ability. Triangulation of evidence across observational and MR methods is a strength, but the genetic variants associated with smoking initiation may be pleiotropic, suggesting caution in interpreting these results. The nature of this pleiotropy warrants further study.
Collapse
Affiliation(s)
- Suzanne H. Gage
- Department of Psychological Sciences, University of Liverpool, Liverpool, UK
| | - Hannah M. Sallis
- School of Psychological Science, University of Bristol, Bristol, UK
- MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK
| | - Glenda Lassi
- School of Psychological Science, University of Bristol, Bristol, UK
- MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK
- Translational Science and Experimental Medicine, Research and Early Development, Respiratory & Immunology BioPharmaceuticals R&D, AstraZeneca, Cambridge, UK
| | - Robyn E. Wootton
- School of Psychological Science, University of Bristol, Bristol, UK
- MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK
| | - Claire Mokrysz
- Clinical Psychopharmacology Unit, University College London, London, UK
| | - George Davey Smith
- MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK
- School of Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Marcus R. Munafò
- School of Psychological Science, University of Bristol, Bristol, UK
- MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK
| |
Collapse
|
8
|
Becker ABC, Lüken LM, Kelker L, Holtmann M, Daseking M, Legenbauer T. Cognitive Profiles of Adolescent Inpatients with Substance Use Disorder. CHILDREN 2022; 9:children9050756. [PMID: 35626933 PMCID: PMC9139439 DOI: 10.3390/children9050756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/19/2022] [Accepted: 05/19/2022] [Indexed: 11/16/2022]
Abstract
The prevalence of substance abuse is high during adolescence, and several studies have linked the use of alcohol and cannabis in adolescence to different cognitive impairments. To investigate whether specific cognitive deficits can be observed in adolescents with substance use disorder (SUD), we compared the cognitive profiles of inpatient adolescents diagnosed with SUD to a control group matched for sex, age and educational status. The inpatient adolescents received diagnoses of cannabis use disorder, alcohol use disorder or both. We compared the WISC-V profiles of 22 inpatients (45.5% female, Mage: 14.5; SD: 0.8) and the WAIS-IV profiles of 27 inpatients (44.4% female, Mage: 17.1; SD: 0.9) to 49 matched control participants with no diagnosed SUD. At the time of testing, participants were hospitalized for treatment of their SUD and were abstinent for a period of at least 6 weeks. To gain greater power, we jointly analyzed the Verbal Comprehension Index, Working Memory Index, Processing Speed Index and Full Scale IQ as assessed by WISC-V and WAIS-IV. The clinical group performed significantly worse than the control group on all the above indices. When only the group of inpatients was observed, in a model with the factors sex, educational status, presence of a comorbid diagnosis of depression and the number of comorbid diagnoses, only the factor educational status was significantly associated with the Full Scale IQ, whereas the factors sex and a comorbid diagnosis of depression in this group were associated with the Processing Speed Index. The results show that adolescents diagnosed with SUD (cannabis and/or alcohol) display broad cognitive impairments after 6 weeks of abstinence. Future research is required to further explore the role of comorbid diagnoses.
Collapse
Affiliation(s)
- Angelika Beate Christiane Becker
- Department of Educational Psychology, Helmut-Schmidt-University/University of the Federal Armed Forces, 22043 Hamburg, Germany; (L.K.); (M.D.)
- Correspondence:
| | - Luisa Marie Lüken
- LWL University Hospital for Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, Ruhr University Bochum, 59071 Hamm, Germany; (L.M.L.); (M.H.); (T.L.)
- Department of Psychology, University of Münster, 48149 Münster, Germany
| | - Lea Kelker
- Department of Educational Psychology, Helmut-Schmidt-University/University of the Federal Armed Forces, 22043 Hamburg, Germany; (L.K.); (M.D.)
| | - Martin Holtmann
- LWL University Hospital for Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, Ruhr University Bochum, 59071 Hamm, Germany; (L.M.L.); (M.H.); (T.L.)
| | - Monika Daseking
- Department of Educational Psychology, Helmut-Schmidt-University/University of the Federal Armed Forces, 22043 Hamburg, Germany; (L.K.); (M.D.)
| | - Tanja Legenbauer
- LWL University Hospital for Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, Ruhr University Bochum, 59071 Hamm, Germany; (L.M.L.); (M.H.); (T.L.)
| |
Collapse
|
9
|
Abate SM, Chekol YA, Minaye SY. Prevalence and risk factors of psychoactive substance abuse among students in Ethiopia: A systematic review and meta-analysis. Ann Med Surg (Lond) 2021; 70:102790. [PMID: 34540211 PMCID: PMC8437783 DOI: 10.1016/j.amsu.2021.102790] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 08/24/2021] [Accepted: 09/02/2021] [Indexed: 01/08/2023] Open
Abstract
Background Substance uses were seen in 18–25 years old age groups who are more than 40% world population, from which Africa was the region with the highest proportion accounting 60% in 2016. This review aimed to assess the burden of substance abuse among students in Ethiopia. Methods A comprehensive search was conducted in PubMed/Medline; Science direct and African Online Journal without language and date restriction. The Heterogeneity among the included studies was checked with forest plot, χ2 test, I2 test, and the p-values. All cross-sectional studies reporting rate of prevalence of psychoactive substance among students were included and the rest were excluded. Result A total of 545 articles were identified from different databases and 42 articles were selected for evaluation. Twenty-nine Articles with 22, 012 participants were included. The overall prevalence of psychoactive substance abuse was 32.28% (95% confidence interval (CI): 26.74 to 37.82). Conclusion The review revealed that one-third of the high school and higher education students used different psychoactive substances in Ethiopia. Registration This Systematic Review and Meta-Analysis was registered in Prospero international prospective register of systemic reviews (CRD42020146656) on April 28/2020. One-third of the high school and higher education students used different psychoactive substances in Ethiopia. The overall prevalence of psychoactive substance abuse among high School students in Ethiopia is approximately 30%. Pear pressure is accountable for substance abuse among students in more than 27.95% of the time. The lifetime prevalence of more than two substance abuse was approximately forty percent.
Collapse
Affiliation(s)
- Semagn Mekonnen Abate
- Department of Anesthesiology, College of Health Sciences and Medicine, Dilla University, Dilla, Ethiopia
| | - Yigrem Ali Chekol
- Department of Psychiatry, College of Health Sciences and Medicine, Dilla University, Dilla, Ethiopia
| | - Solomon Yimer Minaye
- Department of Psychiatry, College of Health Sciences and Medicine, Dilla University, Dilla, Ethiopia
| |
Collapse
|
10
|
Hájková M, Knížková K, Siroňová A, Keřková B, Jonáš J, Šustová P, Dorazilová A, Rodriguez M. Cognitive performance and lifetime cannabis use in patients with first-episode schizophrenia spectrum disorder. Cogn Neuropsychiatry 2021; 26:257-272. [PMID: 33973827 DOI: 10.1080/13546805.2021.1924649] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Cognitive impairment is among the core features of schizophrenia. In a healthy population, the cognitive deficit is often linked with cannabis abuse, and although the same would be expected in patients with schizophrenia, research has presented contradictory results. METHODS Participants were patients with first-episode schizophrenia (FES) spectrum disorder who had been lifetime cannabis users (N = 30), FES non-users (N = 53) as well as healthy controls (HC) also divided into cannabis users (N = 20) and non-users (N = 49). All participants underwent an extensive neurocognitive assessment and filled in a cannabis questionnaire, which allowed for a comparison of the four groups on cognitive functioning. RESULTS FES patients using cannabis showed less impaired cognitive functioning with the most prominent difference in visual memory compared to FES non-users. However, they differed neither in the clinical assessment of general psychopathology, positive and negative symptoms, nor in medication from the patient's non-users. A comparison of the HC who used cannabis, and those who did not, revealed no sizeable differences in cognitive performance between the groups. CONCLUSIONS The results delivered supporting evidence for the trend of superior neurocognitive performance in FES patients with a lifetime history of cannabis use compared to non-using patients.
Collapse
Affiliation(s)
- M Hájková
- Institut of Neuropsychiatric Care, Prague, Czech Republic.,Military University Hospital Prague, Prague, Czech Republic
| | - K Knížková
- National Institute of Mental Health, Klecany, Czech Republic.,Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - A Siroňová
- National Institute of Mental Health, Klecany, Czech Republic.,Department of Psychology, Faculty of Social Studies, Masaryk University, Brno, Czech Republic
| | - B Keřková
- National Institute of Mental Health, Klecany, Czech Republic
| | - J Jonáš
- National Institute of Mental Health, Klecany, Czech Republic.,Department of Psychology, Faculty of Arts, Charles University in Prague, Prague, Czech Republic
| | - P Šustová
- National Institute of Mental Health, Klecany, Czech Republic.,Department of Psychology, Faculty of Arts, Charles University in Prague, Prague, Czech Republic
| | - A Dorazilová
- National Institute of Mental Health, Klecany, Czech Republic
| | - M Rodriguez
- National Institute of Mental Health, Klecany, Czech Republic.,Department of Psychology, Faculty of Arts, Charles University in Prague, Prague, Czech Republic
| |
Collapse
|
11
|
Initiation of Moderately Frequent Cannabis use in Adolescence and Young Adulthood is Associated with Declines in Verbal Learning and Memory: A Longitudinal Comparison of Pre- versus Post-Initiation Cognitive Performance. J Int Neuropsychol Soc 2021; 27:621-636. [PMID: 34261549 PMCID: PMC8486043 DOI: 10.1017/s1355617721000631] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVE Cannabis use is associated with relative cognitive weaknesses as observed by cross-sectional as well as longitudinal research. Longitudinal studies, controlling for relevant confounds, are necessary to differentiate premorbid from post-initiation contributions to these effects. METHODS We followed a sample of adolescents and young adults across ten years. Participants provided neurocognitive data and substance use information at two-year intervals. Participants who initiated cannabis and/or alcohol use were identified (n = 86) and split into alcohol-only initiators (n = 39) and infrequent (n = 29) and moderately frequent (n = 18) cannabis initiators. Participants completed the Rey Auditory Verbal Learning Task (RAVLT) and the Iowa Gambling Task (IGT). Group differences before and after substance use initiation and the extent to which alcohol, nicotine, and cannabis use frequencies contributed to cognitive functions over time were examined. RESULTS After controlling for parental education, RAVLT new learning was worse in moderately frequent cannabis users prior to use initiation. RAVLT total learning and delayed recall showed significant declines from pre- to post-initiation in moderately frequent cannabis users. Regression analyses confirmed that frequencies of cannabis, but not alcohol, use contributed to post-initiation variations. Nicotine use showed an independent negative association with delayed memory. Findings for the IGT were not significant. CONCLUSIONS Verbal learning and memory may be disrupted following the initiation of moderately frequent cannabis use while decreased new learning may represent a premorbid liability. Our use of a control group of alcohol-only users adds interpretive clarity to the findings and suggests that future studies should carefully control for comorbid substance use.
Collapse
|
12
|
Ramsay H, Surcel HM, Björnholm L, Kerkelä M, Khandaker GM, Veijola J. Associations Between Maternal Prenatal C-Reactive Protein and Risk Factors for Psychosis in Adolescent Offspring: Findings From the Northern Finland Birth Cohort 1986. Schizophr Bull 2021; 47:766-775. [PMID: 33202018 PMCID: PMC8084441 DOI: 10.1093/schbul/sbaa152] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Prenatal infection is associated with brain structural and functional abnormalities and may increase the risk for psychosis through a direct effect on neurodevelopment. Various infections may exert their effect through a proinflammatory immune response but studies of prenatal maternal inflammatory markers and offspring neurodevelopment are scarce. Using the longitudinal Northern Finland Birth Cohort 1986 study, we examined the associations of maternal prenatal C-reactive protein (CRP) levels with psychosis risk factors in adolescent offspring. CRP was measured in maternal sera collected in pregnancy. In offspring, school performance was measured at age 7 years, while school performance, psychotic experiences, and cannabis use were measured at age 16 years. We tested associations of CRP with offspring measures using regression analysis controlling for offspring sex, maternal education level, and prenatal maternal body mass index, smoking and alcohol use in pregnancy, place of birth, maternal psychiatric admission, paternal psychiatric admission, mothers age at birth, and gestational week of CRP sample. We also tested if adolescent cannabis use mediated the associations between maternal CRP and offspring outcomes. Controlling for covariates, maternal CRP was associated with academic performance at age 16 years (beta = .062, 95% CI = 0.036-0.088), but not with possible psychotic experiences at 16 years (odds ratio [OR] = 1.09, 95% CI = 0.96-1.24). Maternal CRP was also associated with adolescent cannabis use (OR = 1.24, 95% CI = 1.07-1.43). These findings suggest that prenatal inflammation may influence later mental illness risk by affecting neurodevelopment and also indirectly by increasing the risk of exposure to cannabis.
Collapse
Affiliation(s)
- Hugh Ramsay
- Department of Psychiatry, Research Unit of Clinical Neuroscience, University of Oulu, Oulu, Finland
- Department of Psychiatry, Trinity College, Dublin, Ireland
| | - Heljä-Marja Surcel
- Faculty of Medicine, University of Oulu, Oulu, Finland
- Biobank Borealis of Northern Finland, Oulu University Hospital, Oulu, Finland
| | - Lassi Björnholm
- Department of Psychiatry, Research Unit of Clinical Neuroscience, University of Oulu, Oulu, Finland
| | - Martta Kerkelä
- Department of Psychiatry, Research Unit of Clinical Neuroscience, University of Oulu, Oulu, Finland
| | - Golam M Khandaker
- Department of Psychiatry, University of Cambridge, Cambridge, UK
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| | - Juha Veijola
- Department of Psychiatry, Research Unit of Clinical Neuroscience, University of Oulu, Oulu, Finland
- Department of Psychiatry, Oulu University Hospital, Oulu, Finland
- Medical Research Center, Oulu University Hospital and University of Oulu, Oulu, Finland
| |
Collapse
|
13
|
Schaefer JD, Hamdi NR, Malone SM, Vrieze S, Wilson S, McGue M, Iacono WG. Associations between adolescent cannabis use and young-adult functioning in three longitudinal twin studies. Proc Natl Acad Sci U S A 2021; 118:e2013180118. [PMID: 33782115 PMCID: PMC8040790 DOI: 10.1073/pnas.2013180118] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Observational studies have linked cannabis use to an array of negative outcomes, including psychiatric symptoms, cognitive impairment, and educational and occupational underachievement. These associations are particularly strong when cannabis use occurs in adolescence. Nevertheless, causality remains unclear. The purpose of the present study was thus to examine associations between prospectively assessed adolescent cannabis use and young-adult outcomes (psychiatric, cognitive, and socioeconomic) in three longitudinal studies of twins (n = 3,762). Twins reporting greater cumulative cannabis use in adolescence reported higher levels of psychopathology as well as poorer socioeconomic outcomes in young adulthood. However, cannabis use remained associated only with socioeconomic outcomes (i.e., educational attainment, occupational status, and income) in monozygotic-cotwin control analyses, which account fully for shared genetic and environmental confounding. Follow-up analyses examining associations between twin differences in adolescent cannabis use and longitudinal change in academic functioning during the middle- and high-school years provided a possible mechanism for these associations, indicating that greater cannabis use during this period was associated with decreases in grade point average and academic motivation as well as increases in academic problem behavior and school disciplinary problems. Our findings thus suggest that cannabis use in adolescence has potentially causal, deleterious effects on adolescent academic functioning and young-adult socioeconomic outcomes despite little evidence suggesting a strong, causal influence on adult mental health or cognitive ability.
Collapse
Affiliation(s)
- Jonathan D Schaefer
- Institute of Child Development, University of Minnesota, Minneapolis, MN 55455;
| | - Nayla R Hamdi
- Northwest Metro VA Clinic, Minneapolis Veterans Affairs Health Care System, Ramsey, MN 55303
| | - Stephen M Malone
- Department of Psychology, University of Minnesota, Minneapolis, MN 55455
| | - Scott Vrieze
- Department of Psychology, University of Minnesota, Minneapolis, MN 55455
| | - Sylia Wilson
- Institute of Child Development, University of Minnesota, Minneapolis, MN 55455
| | - Matt McGue
- Department of Psychology, University of Minnesota, Minneapolis, MN 55455
| | - William G Iacono
- Department of Psychology, University of Minnesota, Minneapolis, MN 55455
| |
Collapse
|
14
|
Mahedy L, Wootton R, Suddell S, Skirrow C, Field M, Heron J, Hickman M, Munafò MR. Testing the association between tobacco and cannabis use and cognitive functioning: Findings from an observational and Mendelian randomization study. Drug Alcohol Depend 2021; 221:108591. [PMID: 33618197 PMCID: PMC8047806 DOI: 10.1016/j.drugalcdep.2021.108591] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 12/17/2020] [Accepted: 01/17/2021] [Indexed: 01/08/2023]
Abstract
BACKGROUND Although studies have examined the association between tobacco and cannabis use in adolescence with subsequent cognitive functioning, study designs are usually not able to distinguish correlation from causation. METHODS Separate patterns of tobacco and cannabis use were derived using longitudinal latent class analysis based on measures assessed on five occasions from age 13-18 in a large UK population cohort (Avon Longitudinal Study of Parents and Children). Cognitive functioning measures comprised of working memory, response inhibition, and emotion recognition assessed at 24 years of age. Mendelian randomization was used to examine the possible causal relationship between smoking initiation, lifetime cannabis use and cognitive functioning. RESULTS We found evidence of a relationship between tobacco and cannabis use and diminished cognitive functioning for each of the outcomes in the observational analyses. There was evidence to suggest that late-onset regular tobacco smokers (b=-0.29, 95 %CI=-0.45 to -0.13), early-onset regular tobacco smokers (b=-0.45, 95 %CI=-0.84 to -0.05), and early-onset regular cannabis users (b=-0.62, 95 %CI=-0.93 to -0.31) showed poorer working memory. Early-onset regular tobacco smokers (b = 0.18, 95 %CI = 0.07 to 0.28), and early-onset regular cannabis users (b = 0.30, 95 %CI = 0.08 to 0.52) displayed poorer ability to inhibit responses. Late-onset regular (b=-0.02, 95 %CI=-0.03 to - 0.00), and early-onset regular tobacco smokers (b=-0.04, 95 %CI=-0.08 to -0.01) showed poorer ability to recognise emotions. Mendelian randomization analyses were imprecise and did not provide additional support for the observational results. CONCLUSION There was some evidence to suggest that adolescent tobacco and cannabis use were associated with deficits in working memory, response inhibition and emotion recognition. Better powered genetic studies are required to determine whether these associations are causal.
Collapse
Affiliation(s)
- Liam Mahedy
- School of Psychological Science, University of Bristol, Bristol, BS8 1TU, UK; MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK; National Institute for Health Research Biomedical Research Centre at the University Hospitals Bristol NHS Foundation Trust and the University of Bristol, Bristol, UK.
| | - Robyn Wootton
- School of Psychological Science, University of Bristol, Bristol, BS8 1TU, UK; MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK; National Institute for Health Research Biomedical Research Centre at the University Hospitals Bristol NHS Foundation Trust and the University of Bristol, Bristol, UK.
| | - Steph Suddell
- School of Psychological Science, University of Bristol, Bristol, BS8 1TU, UK; MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK; National Institute for Health Research Biomedical Research Centre at the University Hospitals Bristol NHS Foundation Trust and the University of Bristol, Bristol, UK.
| | - Caroline Skirrow
- School of Psychological Science, University of Bristol, Bristol, BS8 1TU, UK; Cambridge Cognition, Cambridge, UK.
| | - Matt Field
- Department of Psychology, University of Sheffield, Sheffield, S1 2LT, UK.
| | - Jon Heron
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, BS8 2BN, UK.
| | - Matthew Hickman
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, BS8 2BN, UK.
| | - Marcus R Munafò
- School of Psychological Science, University of Bristol, Bristol, BS8 1TU, UK; MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK; National Institute for Health Research Biomedical Research Centre at the University Hospitals Bristol NHS Foundation Trust and the University of Bristol, Bristol, UK.
| |
Collapse
|
15
|
Cannabis use and psychosocial functioning: evidence from prospective longitudinal studies. Curr Opin Psychol 2021; 38:19-24. [DOI: 10.1016/j.copsyc.2020.07.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/26/2020] [Accepted: 07/01/2020] [Indexed: 01/31/2023]
|
16
|
Helmer SM, Burkhart G, Matias J, Buck C, Engling Cardoso F, Vicente J. "Tell Me How Much Your Friends Consume"-Personal, Behavioral, Social, and Attitudinal Factors Associated with Alcohol and Cannabis Use among European School Students. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:1684. [PMID: 33578655 PMCID: PMC7916343 DOI: 10.3390/ijerph18041684] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/31/2021] [Accepted: 02/08/2021] [Indexed: 11/16/2022]
Abstract
BACKGROUND Substance use in European adolescents remains a serious health concern. Assessing what affects adolescents' substance use is crucial for implementing effective prevention. This study aims to examine alcohol and cannabis use-related behavioral, social, and attitudinal variables that might directly be considered to guide prevention responses for adolescents. METHODS Cross-sectional data of 78,554 15-16-year-old school students from the 2011 European School Survey Project on Alcohol and Other Drugs (ESPAD) from 26 European countries were analyzed. Self-reported drunkenness in the last 30 days and cannabis use in the last 12 months served as dependent variables. To investigate which factors are associated with risky substance use, multivariable logistic regressions were used. RESULTS 17.7% of respondents reported drunkenness in the last 30 days, and 14.9% used cannabis in the last 12 months. The most important predictor for risky substance use was the perception that most/all of their friends engaged in substance use behavior, followed by lack of parental support, low personal adherence to rules, and low school performance. CONCLUSION Interventions addressing the perceived descriptive norms either directly or by changing environmental cues, opportunities, and regulations, as well as effective parenting and academic support may prevent and reduce risky substance use behavior among adolescents.
Collapse
Affiliation(s)
- Stefanie M. Helmer
- Institute for Health and Nursing Science, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 13353 Berlin, Germany
| | - Gregor Burkhart
- European Monitoring Centre for Drugs and Drug Addiction, 1249-289 Lisbon, Portugal; (G.B.); (J.M.); (F.E.C.); (J.V.)
| | - João Matias
- European Monitoring Centre for Drugs and Drug Addiction, 1249-289 Lisbon, Portugal; (G.B.); (J.M.); (F.E.C.); (J.V.)
| | - Christoph Buck
- Leibniz Institute for Prevention Research and Epidemiology—BIPS, 28359 Bremen, Germany;
| | - Feline Engling Cardoso
- European Monitoring Centre for Drugs and Drug Addiction, 1249-289 Lisbon, Portugal; (G.B.); (J.M.); (F.E.C.); (J.V.)
| | - Julian Vicente
- European Monitoring Centre for Drugs and Drug Addiction, 1249-289 Lisbon, Portugal; (G.B.); (J.M.); (F.E.C.); (J.V.)
| |
Collapse
|
17
|
Bourque J, Potvin S. Cannabis and Cognitive Functioning: From Acute to Residual Effects, From Randomized Controlled Trials to Prospective Designs. Front Psychiatry 2021; 12:596601. [PMID: 34177633 PMCID: PMC8222623 DOI: 10.3389/fpsyt.2021.596601] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 05/17/2021] [Indexed: 12/30/2022] Open
Abstract
In recent years, several jurisdictions have revised their regulation policy toward both medical and recreational use of cannabis. These changes have elicited concerns regarding how legalization impacts academic achievement and work performance. This review evaluates the acute and long-term (residual) association between cannabis use and cognitive functioning that underlies poor academic and work performance. Relative to other reviews, this article focuses on cross-over randomized controlled trials and prospective designs given that they allow to test the impairing effects of cannabis exposure at the within-subject level. Acute cannabis cognitive effects are discussed separately for known confounding factors such as levels of delta-9-tetrahydrocannabinol (Δ9-THC), Δ9-THC:cannabidiol ratio, previous cannabis use and, comorbidity with psychosis-spectrum disorders. The cognitive residual effects of cannabis are detailed in relation to duration of abstinence, frequency of use, comorbidity with psychosis-spectrum disorders, types of cognitive domains assessed, and age of cannabis use initiation. Moreover, considering the fact that adequate longitudinal studies can make inferences about causality between cannabis use and impaired cognitive functioning when disentangling between-subject from within-subject variation, proofs for the three main non-mutually exclusive hypotheses about this relationship will be presented: i) the cognitive vulnerability hypothesis as part of the more general common antecedent hypothesis, ii) the concurrent cannabis impairing hypothesis, and iii) the neurotoxic hypothesis of cannabis. Current research provides evidence for mild to moderate acute cannabis effects on episodic and working memory, processing speed, and executive functions. Mild residual impairing effects were also observed in these exact same cognitive domains, suggesting that adverse effects following cannabis intoxication persist at least days or weeks following cannabis abstinence. Relative to adult-onset, adolescent-onset cannabis use seems to explain the dose-response relationship and is associated with longer lasting residual effects even in mild users (<weekly). The association between cannabis and cognition is likely explained by common antecedents, such that genetic and shared environment factors predispose individuals to both cannabis use and cognitive deficits, and to a lesser degree, neurotoxic effects.
Collapse
Affiliation(s)
- Josiane Bourque
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Stéphane Potvin
- Department of Psychiatry and Addiction, Faculty of Medicine, University of Montreal, Montreal, QC, Canada.,Centre de Recherche de l'Institut Universitaire en Santé Mentale de Montréal, Montréal, QC, Canada
| |
Collapse
|
18
|
Sorkhou M, Bedder RH, George TP. The Behavioral Sequelae of Cannabis Use in Healthy People: A Systematic Review. Front Psychiatry 2021; 12:630247. [PMID: 33664685 PMCID: PMC7920961 DOI: 10.3389/fpsyt.2021.630247] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 01/25/2021] [Indexed: 12/13/2022] Open
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.
Collapse
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
| |
Collapse
|
19
|
Power E, Sabherwal S, Healy C, O’ Neill A, Cotter D, Cannon M. Intelligence quotient decline following frequent or dependent cannabis use in youth: a systematic review and meta-analysis of longitudinal studies. Psychol Med 2021; 51:194-200. [PMID: 33501901 PMCID: PMC7893511 DOI: 10.1017/s0033291720005036] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 10/22/2020] [Accepted: 12/02/2020] [Indexed: 12/20/2022]
Abstract
Previous systematic reviews and meta-analyses of cross-sectional data assessing the effect of cannabis on cognitive functioning and intelligence show inconsistent results. We hypothesized that frequent and dependent cannabis use in youth would be associated with Intelligence Quotient (IQ) decline. This study is a systematic review and meta-analysis. We searched Embase, PubMed and PsychInfo from inception to 24 January 2020. We included studies with non-treatment seeking samples and pre- and post-exposure measures of IQ. We requested data from authors if summary data was not available from published work. We preregistered our review with PROSPERO (ID no. CRD42019125624). We found seven cohort studies including 808 cases and 5308 controls. We found a significant effect for the association between frequent or dependent cannabis use in youth and IQ change, Cohen's d = -0.132 (95% CI -0.198 to -0.066) p < 0.001. Statistical heterogeneity between studies was also low at I2 = 0.2%. Study quality was moderate to high. This translates to an average decline of approximately 2 IQ points following exposure to cannabis in youth. Future studies should have longer periods of follow up to assess the magnitude of developmental impact.
Collapse
Affiliation(s)
- Emmet Power
- Department of Psychiatry, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital, Dublin 9, Ireland
| | - Sophie Sabherwal
- Department of Psychiatry, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital, Dublin 9, Ireland
| | - Colm Healy
- Department of Psychiatry, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital, Dublin 9, Ireland
| | - Aisling O’ Neill
- Department of Psychiatry, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital, Dublin 9, Ireland
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland
| | - David Cotter
- Department of Psychiatry, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital, Dublin 9, Ireland
| | - Mary Cannon
- Department of Psychiatry, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital, Dublin 9, Ireland
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland
| |
Collapse
|
20
|
Hamidullah S, Thorpe HHA, Frie JA, Mccurdy RD, Khokhar JY. Adolescent Substance Use and the Brain: Behavioral, Cognitive and Neuroimaging Correlates. Front Hum Neurosci 2020; 14:298. [PMID: 32848673 PMCID: PMC7418456 DOI: 10.3389/fnhum.2020.00298] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 07/03/2020] [Indexed: 12/11/2022] Open
Abstract
Adolescence is an important ontogenetic period that is characterized by behaviors such as enhanced novelty-seeking, impulsivity, and reward preference, which can give rise to an increased risk for substance use. While substance use rates in adolescence are generally on a decline, the current rates combined with emerging trends, such as increases in e-cigarette use, remain a significant public health concern. In this review, we focus on the neurobiological divergences associated with adolescent substance use, derived from a cross-sectional, retrospective, and longitudinal studies, and highlight how the use of these substances during adolescence may relate to behavioral and neuroimaging-based outcomes. Identifying and understanding the associations between adolescent substance use and changes in cognition, mental health, and future substance use risk may assist our understanding of the consequences of drug exposure during this critical window.
Collapse
Affiliation(s)
| | - Hayley H A Thorpe
- Department of Biomedical Sciences, University of Guelph, Guelph, ON, Canada
| | - Jude A Frie
- Department of Biomedical Sciences, University of Guelph, Guelph, ON, Canada
| | - Richard D Mccurdy
- Department of Biomedical Sciences, University of Guelph, Guelph, ON, Canada
| | - Jibran Y Khokhar
- Department of Biomedical Sciences, University of Guelph, Guelph, ON, Canada
| |
Collapse
|
21
|
Adolescent cannabis use, cognition, brain health and educational outcomes: A review of the evidence. Eur Neuropsychopharmacol 2020; 36:169-180. [PMID: 32268974 DOI: 10.1016/j.euroneuro.2020.03.012] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 02/10/2020] [Accepted: 03/13/2020] [Indexed: 01/13/2023]
Abstract
We review the findings of systematic reviews and meta-analyses of case-control studies that examine brain functioning and cognitive correlates of adolescent cannabis use using structural and functional neuroimaging tools and standardised neuropsychological tests. We also examine prospective epidemiological studies on the possible effects of adolescent and young adult cannabis use on cognitive performance in adult life and the completion of secondary education. We summarize the findings of studies in each of these areas that have been published since the most recent systematic review. Systematic reviews find that adolescent cannabis use is inconsistently associated with alterations in the structure of prefrontal and temporal brain regions. Meta-analyses reveal functional alterations in the parietal cortex and putamen. Differences in the orbitofrontal cortex predate cannabis use; it is unclear if they are affected by continued cannabis use and prolonged abstinence. Longitudinal and twin studies report larger declines in IQ among cannabis users than their non-using peers but it is unclear whether these findings can be attributed to cannabis use or to genetic, mental health and environmental factors. Several longitudinal studies and a meta-analysis of cross-sectional studies suggest that there is some cognitive recovery after abstinence from cannabis. Longitudinal studies and some twin studies have found that cannabis users are less likely to complete secondary school than their non-using controls. This association might reflect an effect of cannabis use and/or the social environment of cannabis users and their cannabis using peers. Cognitive performance is altered in some domains (e.g. IQ, verbal learning) in young people while they are regularly using cannabis. There are two important messages to adolescents and young adults: First, cannabis has potentially detrimental effects on cognition, brain and educational outcomes that persist beyond acute intoxication. Second, impaired cognitive function in cannabis users appears to improve with sustained abstinence.
Collapse
|
22
|
Hammond CJ, Chaney A, Hendrickson B, Sharma P. Cannabis use among U.S. adolescents in the era of marijuana legalization: a review of changing use patterns, comorbidity, and health correlates. Int Rev Psychiatry 2020; 32:221-234. [PMID: 32026735 PMCID: PMC7588219 DOI: 10.1080/09540261.2020.1713056] [Citation(s) in RCA: 89] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Decriminalization, medicalization, and legalization of cannabis use by a majority of U.S. states over the past 25 years have dramatically shifted societal perceptions and use patterns among Americans. How marijuana policy changes have affected population-wide health of U.S. youth and what the downstream public health implications of marijuana legalization are topics of significant debate. Cannabis remains the most commonly used federally illicit psychoactive drug by U.S. adolescents and is the main drug for which U.S. youth present for substance use treatment. Converging evidence indicates that adolescent-onset cannabis exposure is associated with short- and possibly long-term impairments in cognition, worse academic/vocational outcomes, and increased prevalence of psychotic, mood, and addictive disorders. Odds of negative developmental outcomes are increased in youth with early-onset, persistent, high frequency, and high-potency Δ-9-THC cannabis use, suggesting dose-dependent relationships. Cannabis use disorders are treatable conditions with clear childhood antecedents that respond to targeted prevention and early intervention strategies. This review indicates that marijuana policy changes have had mixed effects on U.S. adolescent health including potential benefits from decriminalization and negative health outcomes evidenced by increases in cannabis-related motor vehicle accidents, emergency department visits, and hospitalizations. Federal and state legislatures should apply a public health framework and consider the possible downstream effects of marijuana policy change on paediatric health.
Collapse
Affiliation(s)
- Christopher J. Hammond
- Division of Child & Adolescent Psychiatry, Johns Hopkins University School of Medicine, Baltimore, Maryland;,Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, Baltimore, Maryland;,Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland;,Corresponding Author address: Christopher Hammond, MD PhD, Johns Hopkins Bayview, 5500 Lombard Street, Baltimore, MD 21224, , Phone: 410-550-0048
- Fax: 410-550-0030
| | - Aldorian Chaney
- Division of Child & Adolescent Psychiatry, Johns Hopkins University School of Medicine, Baltimore, Maryland;,Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Brian Hendrickson
- Division of Child & Adolescent Psychiatry, Johns Hopkins University School of Medicine, Baltimore, Maryland;,Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Pravesh Sharma
- Department of Psychiatry, Mayo Clinic Health System and University of Wisconsin-Eau Claire, Eau Claire, WI
| |
Collapse
|
23
|
Thompson K, Leadbeater B, Ames M, Merrin GJ. Associations Between Marijuana Use Trajectories and Educational and Occupational Success in Young Adulthood. PREVENTION SCIENCE : THE OFFICIAL JOURNAL OF THE SOCIETY FOR PREVENTION RESEARCH 2020; 20:257-269. [PMID: 29704147 PMCID: PMC6414467 DOI: 10.1007/s11121-018-0904-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Adolescence and young adulthood is a critical stage when the economic foundations for life-long health are established. To date, there is little consensus as to whether marijuana use is associated with poor educational and occupational success in adulthood. We investigated associations between trajectories of marijuana use from ages 15 to 28 and multiple indicators of economic well-being in young adulthood including achievement levels (i.e., educational attainment and occupational prestige), work characteristics (i.e., full vs part-time employment, hours worked, annual income), financial strain (i.e., debt, trouble paying for necessities, delaying medical attention), and perceived workplace stress. Data were from the Victoria Healthy Youth Survey, a 10-year prospective study of a randomly recruited community sample of 662 youth (48% male; Mage = 15.5), followed biennially for six assessments. Models adjusted for baseline age, sex, SES, high school grades, heavy drinking, smoking, and internalizing and oppositional defiant disorder symptoms. Chronic users (our highest risk class) reported lower levels of educational attainment, lower occupational prestige, lower income, greater debt, and more difficulty paying for medical necessities in young adulthood compared to abstainers. Similarly, increasers also reported lower educational attainment, occupational prestige, and income. Decreasers, who had high early use but quit over time, showed resilience in economic well-being, performing similar to abstainers. Groups did not differ on employment status or perceived workplace stress. The findings indicate that early onset and persistent high or increasingly frequent use of marijuana in the transition from adolescent to young adulthood is associated with risks for achieving educational and occupational success, and subsequently health, in young adulthood.
Collapse
Affiliation(s)
- Kara Thompson
- Department of Psychology, St. Francis Xavier University, 2323 Notre Dame Ave., Antigonish, NS, B2G 2W5, Canada.
| | | | - Megan Ames
- University of Victoria, Victoria, BC, V8P 5C2, Canada
| | | |
Collapse
|
24
|
Kroon E, Kuhns L, Hoch E, Cousijn J. Heavy cannabis use, dependence and the brain: a clinical perspective. Addiction 2020; 115:559-572. [PMID: 31408248 PMCID: PMC7027478 DOI: 10.1111/add.14776] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 07/15/2019] [Accepted: 08/07/2019] [Indexed: 12/28/2022]
Abstract
AIMS To summarize and evaluate our knowledge of the relationship between heavy cannabis use, cannabis use disorder (CUD) and the brain. METHODS Narrative review of relevant literature identified through existing systematic reviews, meta-analyses and a PubMed search. Epidemiology, clinical representations, potential causal mechanisms, assessments, treatment and prognosis are discussed. RESULTS Although causality is unclear, heavy and dependent cannabis use is consistently associated with a high prevalence of comorbid psychiatric disorders and learning and memory impairments that seem to recover after a period of abstinence. Evidence regarding other cognitive domains and neurological consequences, including cerebrovascular events, is limited and inconsistent. Abstinence after treatment is only achieved in a minority of cases; treatment targeted at reduction in use appears have some success. Potential moderators of the impact of CUD on the brain include age of onset, heaviness of use, CUD severity, the ratio of ∆9-tetrahydrocannabinol to cannabidiol and severity of comorbid disorders. CONCLUSIONS Current evidence of long-term effects of daily cannabis use and cannabis use disorder on brain-related outcomes is suggestive rather than conclusive, but use is associated with psychiatric morbidity and with cognitive impairments that recover after a period of abstinence.
Collapse
Affiliation(s)
- Emese Kroon
- Neuroscience of Addiction Lab, Department of PsychologyUniversity of AmsterdamAmsterdamthe Netherlands
- The Amsterdam Brain and Cognition Center (ABC)University of AmsterdamAmsterdamthe Netherlands
| | - Lauren Kuhns
- Neuroscience of Addiction Lab, Department of PsychologyUniversity of AmsterdamAmsterdamthe Netherlands
- The Amsterdam Brain and Cognition Center (ABC)University of AmsterdamAmsterdamthe Netherlands
| | - Eva Hoch
- Cannabinoid Research and Treatment Group, Department of Psychiatry and PsychotherapyUniversity Hospital, Ludwig Maximilan UniversityMunichGermany
- Division of Clinical Psychology and Psychological Treatment, Department of PsychologyLudwig Maximilian University MunichMunichGermany
| | - Janna Cousijn
- Neuroscience of Addiction Lab, Department of PsychologyUniversity of AmsterdamAmsterdamthe Netherlands
- The Amsterdam Brain and Cognition Center (ABC)University of AmsterdamAmsterdamthe Netherlands
| |
Collapse
|
25
|
Abstract
Objective: Shifting policies and widespread acceptance of cannabis for medical and/or recreational purposes have fueled worries of increased cannabis initiation and use in adolescents. In particular, the adolescent period is thought to be associated with an increased susceptibility to the potential harms of repeated cannabis use, due to being a critical period for neuromaturational events in the brain. This review investigates the neuroimaging evidence of brain harms attributable to adolescent cannabis use. Methods: PubMed and Scopus searches were conducted for empirical articles that examined neuroimaging effects in both adolescent cannabis users and adult user studies that explored the effect of age at cannabis use onset on the brain. Results: We found 43 studies that examined brain effect (structural and functional magnetic resonance imaging) in adolescent cannabis users and 20 that examined the link between onset age of cannabis use and brain effects in adult users. Studies on adolescent cannabis users relative to nonusers mainly implicate frontal and parietal regions and associated brain activation in relation to inhibitory control, reward, and memory. However, studies in adults are more mixed, many of which did not observe an effect of onset age of cannabis use on brain imaging metrics. Conclusions: While there is some evidence of compromised frontoparietal structure and function in adolescent cannabis use, it remains unclear whether the observed effects are specifically attributable to adolescent onset of use or general cannabis use-related factors such as depressive symptoms. The relative contribution of adolescent onset of cannabis use and use chronicity will have to be more comprehensively examined in prospective, longitudinal studies with more rigorous measures of cannabis use (dosage, exposure, dependence, constituent compounds such as the relative cannabinoid levels).
Collapse
Affiliation(s)
- Yann Chye
- Brain Mind and Society Research Hub, Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Melbourne, Australia
| | - Erynn Christensen
- Brain Mind and Society Research Hub, Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Melbourne, Australia
| | - Murat Yücel
- Brain Mind and Society Research Hub, Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Melbourne, Australia
| |
Collapse
|
26
|
Matheson J, Le Foll B. Cannabis Legalization and Acute Harm From High Potency Cannabis Products: A Narrative Review and Recommendations for Public Health. Front Psychiatry 2020; 11:591979. [PMID: 33173527 PMCID: PMC7538627 DOI: 10.3389/fpsyt.2020.591979] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 09/03/2020] [Indexed: 12/12/2022] Open
Abstract
Legalization and commercial sale of non-medical cannabis has led to increasing diversity and potency of cannabis products. Some of the American states that were the first to legalize have seen rises in acute harms associated with cannabis use, e.g. Colorado has seen increases in emergency department visits for cannabis-related acute psychological distress and severe vomiting (hyperemesis), as well as a number of high-profile deaths related to ingestion of high doses of cannabis edibles. Over-ingestion of cannabis is related to multiple factors, including the sale of cannabis products with high levels of THC and consumers' confusion regarding labelling of cannabis products, which disproportionately impact new or inexperienced users. Based on our review of the literature, we propose three approaches to minimizing acute harms: early restriction of cannabis edibles and high-potency products; clear and consistent labelling that communicates dose/serving size and health risks; and implementation of robust data collection frameworks to monitor harms, broken down by cannabis product type (e.g. dose, potency, route of administration) and consumer characteristics (e.g. age, sex, gender, ethnicity). Ongoing data collection and monitoring of harms in jurisdictions that have existing legal cannabis laws will be vital to understanding the impact of cannabis legalization and maximizing public health benefits.
Collapse
Affiliation(s)
- Justin Matheson
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health, Toronto, ON, Canada.,Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Bernard Le Foll
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health, Toronto, ON, Canada.,Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada.,Addictions Division, Centre for Addiction and Mental Health, Toronto, ON, Canada.,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada.,Department of Psychiatry, Faculty of Medicine, University of Toronto, Toronto, ON, Canada.,Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada.,Department of Family and Community Medicine, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
27
|
Müller-Oehring EM, Le Berre AP, Serventi M, Kalon E, Haas AL, Padula CB, Schulte T. Brain activation to cannabis- and alcohol-related words in alcohol use disorder. Psychiatry Res Neuroimaging 2019; 294:111005. [PMID: 31715379 PMCID: PMC6886708 DOI: 10.1016/j.pscychresns.2019.111005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 10/29/2019] [Accepted: 10/31/2019] [Indexed: 12/18/2022]
Abstract
Cannabis abuse commonly co-occurs with alcohol use disorder (AUD). With increased acceptance and accessibility to cannabis in the US, it is imperative to understand the psychological and neural mechanisms of concurrent alcohol and cannabis use. We hypothesized that neural alcohol-cue conditioning may extent to other drug-related stimuli, such as cannabis, and underwrite the loss of control over reward-driven behavior. Task-activated fMRI examined the neural correlates of alcohol- and cannabis-related word cues in 21 abstinent AUD and 18 control subjects. Relative to controls, AUD showed behavioral attentional biases and frontal hypoactivation to both alcohol- and cannabis-related words. This cue-elicited prefrontal hypoactivation was related to higher lifetime alcohol consumption (pcorrected < 0.02) and modulated by past cannabis use histories (p ≦ 0.001). In particular, frontal hypoactivation to both alcohol and cannabis cues was pronounced in AUD without prior cannabis exposure. Overall, frontal control mechanisms in abstinent AUD were not sufficiently engaged to override automatic alcohol and cannabis-related intrusions, enhancing the risk for relapse and potentially for alcohol and cannabis co-use with the increased social acceptance and accessibility in the US.
Collapse
Affiliation(s)
- Eva M Müller-Oehring
- Neuroscience Program, SRI International, Menlo Park, CA, United States; Dept. of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, United States
| | - Anne-Pascale Le Berre
- Dept. of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, United States
| | - Matthew Serventi
- Neuroscience Program, SRI International, Menlo Park, CA, United States; Dept. of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, United States
| | - Ember Kalon
- Neuroscience Program, SRI International, Menlo Park, CA, United States; Dept. of Psychology, Palo Alto University, Palo Alto, CA, United States
| | - Amie L Haas
- Dept. of Psychology, Palo Alto University, Palo Alto, CA, United States
| | - Claudia B Padula
- Dept. of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, United States; VA Palo Alto Health Care System, Palo Alto, CA, United States
| | - Tilman Schulte
- Neuroscience Program, SRI International, Menlo Park, CA, United States; Dept. of Psychology, Palo Alto University, Palo Alto, CA, United States.
| |
Collapse
|
28
|
Abstract
Eleven US States and the District of Columbia legally allow personal (i.e., recreational) cannabis use by adults, and an additional 22 states allow use of cannabis for medicinal purposes. Of these jurisdictions, only two do not have some form of legalized gambling available (https://www.casino.org/local/guide/). In contrast to this rapid increase in legally available marijuana is the limited knowledge about the intersection of cannabis use and gambling. This paper strives to define the current status of the relevant literatures and consider the implication for future gambling research. We describe the research literature on the prevalence of cannabis use and co-existing gambling problems and the effects of cannabis use on gambling-related cognitive functions and decision-making. We also discuss clinical considerations with treating problem gamblers with a cannabis use disorder. Finally, the potential implications for responsible gambling practices and policies and the most pressing gaps in the research literature are offered.
Collapse
Affiliation(s)
- Ken C Winters
- Oregon Research Institute (MN location), 1575 Northrop St., Falcon Heights, MN, 55108, USA.
| | - James P Whelan
- Department of Psychology, University of Memphis, 400 Innovation Drive, Memphis, TN, 38152-3032, USA
| |
Collapse
|
29
|
Abstract
As an increasing number of states legalize cannabis use for recreational and/or medical purposes, it is increasingly important to understand the neural and cognitive consequences of recreational cannabis use in adolescent consumers. Adolescence is marked by ongoing neuromaturational processes, making this a particularly vulnerable period, particularly regarding exposure to drugs, including cannabis. This review highlights evidence from studies documenting the neural impact of cannabis use in adolescence and explores mediating factors related to cannabis use.
Collapse
Affiliation(s)
- Yasmin Mashhoon
- Department of Psychiatry, Harvard Medical School, 2 West, Room 305, 401 Park Drive, Boston, MA 02215, USA; Behavioral Psychopharmacology Research Laboratory, McLean Imaging Center, Mclean Hospital, 115 Mill Street, Mailstop 204, Belmont, MA 02478, USA
| | - Kelly A Sagar
- Department of Psychiatry, Harvard Medical School, 2 West, Room 305, 401 Park Drive, Boston, MA 02215, USA; Cognitive and Clinical Neuroimaging Core, McLean Hospital, McLean Imaging Center, 115 Mill Street, Mailstop 204, Belmont, MA 02478, USA; Marijuana Investigations for Neuroscientific Discovery, McLean Hospital, McLean Imaging Center, 115 Mill Street, Mailstop 204, Belmont, MA 02478, USA
| | - Staci A Gruber
- Department of Psychiatry, Harvard Medical School, 2 West, Room 305, 401 Park Drive, Boston, MA 02215, USA; Cognitive and Clinical Neuroimaging Core, McLean Hospital, McLean Imaging Center, 115 Mill Street, Mailstop 204, Belmont, MA 02478, USA; Marijuana Investigations for Neuroscientific Discovery, McLean Hospital, McLean Imaging Center, 115 Mill Street, Mailstop 204, Belmont, MA 02478, USA.
| |
Collapse
|
30
|
Petker T, Owens MM, Amlung MT, Oshri A, Sweet LH, MacKillop J. Cannabis involvement and neuropsychological performance: findings from the Human Connectome Project. J Psychiatry Neurosci 2019; 44:414-422. [PMID: 31245962 PMCID: PMC6821511 DOI: 10.1503/jpn.180115] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND There is evidence that heavy cannabis use is associated with decrements in cognitive performance, but findings are mixed and studies are often limited by small sample sizes and narrow adjustment for potential confounding variables. In a comparatively large sample, the current study examined associations between multiple indicators of cannabis use in relation to performance on a variety of neuropsychological tasks. METHODS Participants were 1121 adults (54% female) enrolled in the Human Connectome Project. Cannabis involvement comprised recent cannabis use (positive tetrahydrocannabinol screen), total number of lifetime uses, cannabis use disorder and age at first use. The neuropsychological battery comprised performance in episodic memory, fluid intelligence, attention, working memory, executive function, impulsive decision-making, processing speed and psychomotor dexterity. Covariates were age, sex, income, family structure and alcohol and tobacco use. RESULTS Positive urinary tetrahydrocannabinol status was associated with worse performance in episodic memory and processing speed, and positive cannabis use disorder status was associated with lower fluid intelligence (all p < 0.005). No other significant associations were present. LIMITATIONS The sample was limited to young adults aged 22–36 years. The measures of cannabis involvement were relatively coarse. CONCLUSION Beyond an array of potential confounders, recent cannabis use was associated with deficits in memory and psychomotor performance, and cannabis use disorder was associated with lower overall cognitive functioning in a large normative sample of adults. The findings pertaining to recent use have particular relevance for occupational settings.
Collapse
Affiliation(s)
- Tashia Petker
- From the Peter Boris Centre for Addictions Research, McMaster University/St. Joseph’s Healthcare Hamilton, Hamilton, Ont., Canada (Petker, Amlung, MacKillop); the Department of Psychology, Neuroscience, and Behaviour, McMaster University, Hamilton, Ont., Canada (Petker, Amlung, MacKillop); the Addiction Medicine Service, Homewood Health Centre, Guelph, Ont., Canada (Petker, Owens); the Department of Psychology, University of Georgia, Athens, GA, USA (Sweet, MacKillop); the Michael G. DeGroote Centre for Medicinal Cannabis Research, McMaster University/St. Joseph’s Healthcare Hamilton, Hamilton, Ont., Canada (Amlung, MacKillop); the Department of Human Development and Family Science, University of Georgia, Athens, GA, USA (Oshri); the Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA (Sweet); and the Homewood Research Institute, Guelph, Ont., Canada (MacKillop)
| | - Max M. Owens
- From the Peter Boris Centre for Addictions Research, McMaster University/St. Joseph’s Healthcare Hamilton, Hamilton, Ont., Canada (Petker, Amlung, MacKillop); the Department of Psychology, Neuroscience, and Behaviour, McMaster University, Hamilton, Ont., Canada (Petker, Amlung, MacKillop); the Addiction Medicine Service, Homewood Health Centre, Guelph, Ont., Canada (Petker, Owens); the Department of Psychology, University of Georgia, Athens, GA, USA (Sweet, MacKillop); the Michael G. DeGroote Centre for Medicinal Cannabis Research, McMaster University/St. Joseph’s Healthcare Hamilton, Hamilton, Ont., Canada (Amlung, MacKillop); the Department of Human Development and Family Science, University of Georgia, Athens, GA, USA (Oshri); the Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA (Sweet); and the Homewood Research Institute, Guelph, Ont., Canada (MacKillop)
| | - Michael T. Amlung
- From the Peter Boris Centre for Addictions Research, McMaster University/St. Joseph’s Healthcare Hamilton, Hamilton, Ont., Canada (Petker, Amlung, MacKillop); the Department of Psychology, Neuroscience, and Behaviour, McMaster University, Hamilton, Ont., Canada (Petker, Amlung, MacKillop); the Addiction Medicine Service, Homewood Health Centre, Guelph, Ont., Canada (Petker, Owens); the Department of Psychology, University of Georgia, Athens, GA, USA (Sweet, MacKillop); the Michael G. DeGroote Centre for Medicinal Cannabis Research, McMaster University/St. Joseph’s Healthcare Hamilton, Hamilton, Ont., Canada (Amlung, MacKillop); the Department of Human Development and Family Science, University of Georgia, Athens, GA, USA (Oshri); the Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA (Sweet); and the Homewood Research Institute, Guelph, Ont., Canada (MacKillop)
| | - Assaf Oshri
- From the Peter Boris Centre for Addictions Research, McMaster University/St. Joseph’s Healthcare Hamilton, Hamilton, Ont., Canada (Petker, Amlung, MacKillop); the Department of Psychology, Neuroscience, and Behaviour, McMaster University, Hamilton, Ont., Canada (Petker, Amlung, MacKillop); the Addiction Medicine Service, Homewood Health Centre, Guelph, Ont., Canada (Petker, Owens); the Department of Psychology, University of Georgia, Athens, GA, USA (Sweet, MacKillop); the Michael G. DeGroote Centre for Medicinal Cannabis Research, McMaster University/St. Joseph’s Healthcare Hamilton, Hamilton, Ont., Canada (Amlung, MacKillop); the Department of Human Development and Family Science, University of Georgia, Athens, GA, USA (Oshri); the Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA (Sweet); and the Homewood Research Institute, Guelph, Ont., Canada (MacKillop)
| | - Lawrence H. Sweet
- From the Peter Boris Centre for Addictions Research, McMaster University/St. Joseph’s Healthcare Hamilton, Hamilton, Ont., Canada (Petker, Amlung, MacKillop); the Department of Psychology, Neuroscience, and Behaviour, McMaster University, Hamilton, Ont., Canada (Petker, Amlung, MacKillop); the Addiction Medicine Service, Homewood Health Centre, Guelph, Ont., Canada (Petker, Owens); the Department of Psychology, University of Georgia, Athens, GA, USA (Sweet, MacKillop); the Michael G. DeGroote Centre for Medicinal Cannabis Research, McMaster University/St. Joseph’s Healthcare Hamilton, Hamilton, Ont., Canada (Amlung, MacKillop); the Department of Human Development and Family Science, University of Georgia, Athens, GA, USA (Oshri); the Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA (Sweet); and the Homewood Research Institute, Guelph, Ont., Canada (MacKillop)
| | - James MacKillop
- From the Peter Boris Centre for Addictions Research, McMaster University/St. Joseph’s Healthcare Hamilton, Hamilton, Ont., Canada (Petker, Amlung, MacKillop); the Department of Psychology, Neuroscience, and Behaviour, McMaster University, Hamilton, Ont., Canada (Petker, Amlung, MacKillop); the Addiction Medicine Service, Homewood Health Centre, Guelph, Ont., Canada (Petker, Owens); the Department of Psychology, University of Georgia, Athens, GA, USA (Sweet, MacKillop); the Michael G. DeGroote Centre for Medicinal Cannabis Research, McMaster University/St. Joseph’s Healthcare Hamilton, Hamilton, Ont., Canada (Amlung, MacKillop); the Department of Human Development and Family Science, University of Georgia, Athens, GA, USA (Oshri); the Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA (Sweet); and the Homewood Research Institute, Guelph, Ont., Canada (MacKillop)
| |
Collapse
|
31
|
Pacheco-Colón I, Ramirez AR, Gonzalez R. Effects of Adolescent Cannabis Use on Motivation and Depression: A Systematic Review. CURRENT ADDICTION REPORTS 2019; 6:532-546. [PMID: 34079688 DOI: 10.1007/s40429-019-00274-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Purpose of review This article reviews recent behavioral and neuroimaging studies to elucidate whether adolescent cannabis use is related to reduced motivation and increased risk of depression. Recent findings Recent work suggests that heavy adolescent cannabis use predicts poorer educational outcomes, often presumed to reflect reduced academic motivation, as well as increased levels of depressive symptoms. However, evidence of a link between cannabis use and general motivation was lacking. Factors such as concurrent alcohol and tobacco use, trajectories of cannabis use during adolescence, and cannabis-related changes in underlying neurocircuitry may impact associations among cannabis use, motivation, and depression. Summary Heavy adolescent cannabis use is associated with poorer educational outcomes and increased levels of depressive symptoms. The role of depression in how cannabis may affect motivation, broadly, is not yet clear, as most studies have not examined associations among all three constructs. Future work should explore possible overlap between cannabis effects on motivation and depression, and clarify the temporality of these associations.
Collapse
Affiliation(s)
- Ileana Pacheco-Colón
- Center for Children and Families, Department of Psychology, Florida International University
| | - Ana Regina Ramirez
- Center for Children and Families, Department of Psychology, Florida International University
| | - Raul Gonzalez
- Center for Children and Families, Department of Psychology, Florida International University
| |
Collapse
|
32
|
Jacobus J, Courtney KE, Hodgdon EA, Baca R. Cannabis and the developing brain: What does the evidence say? Birth Defects Res 2019; 111:1302-1307. [PMID: 31385460 DOI: 10.1002/bdr2.1572] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 07/19/2019] [Accepted: 07/23/2019] [Indexed: 12/12/2022]
Abstract
Cannabis use during adolescence has been linked to deleterious effects on brain integrity. This article summarizes findings from two prospective investigations (3 and 6 years, on average) on adolescent cannabis use from our laboratory that utilize structural neuroimaging and neurocognitive assessment approaches. Across most studies, findings suggest recency, frequency, and age of onset of cannabis use are likely key variables in predicting poorer neural health outcomes. There is some evidence that preexisting differences in brain architecture may also contribute to vulnerability and outcome differences. Ongoing large-scale prospective studies of youth will be able to disentangle how both cannabis use as well as pre and postexposure differences play a role in divergent outcomes among youth who use cannabis.
Collapse
Affiliation(s)
- Joanna Jacobus
- Department of Psychiatry, University of California, San Diego, California
| | - Kelly E Courtney
- Department of Psychiatry, University of California, San Diego, California
| | | | - Rachel Baca
- Department of Psychiatry, University of California, San Diego, California
| |
Collapse
|
33
|
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. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2019; 45:563-579. [PMID: 31365275 PMCID: PMC7027431 DOI: 10.1080/00952990.2019.1634086] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [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.
Collapse
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
| |
Collapse
|
34
|
Śledziński P, Zeyland J, Slomski R, Nowak-Terpiłowska A. The adverse effects of marijuana use: The present state and future directions. JOURNAL OF CHILD & ADOLESCENT SUBSTANCE ABUSE 2019. [DOI: 10.1080/1067828x.2018.1561580] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Paweł Śledziński
- Department of Biochemistry and Biotechnology, Poznań University of Life Sciences, Poznań, Poland
| | - Joanna Zeyland
- Department of Biochemistry and Biotechnology, Poznań University of Life Sciences, Poznań, Poland
| | - Ryszard Slomski
- Department of Biochemistry and Biotechnology, Poznań University of Life Sciences, Poznań, Poland
- Institute of Human Genetics of the Polish Academy of Sciences, Poznań, Poland
| | | |
Collapse
|
35
|
Sagar KA, Gruber SA. Interactions between recreational cannabis use and cognitive function: lessons from functional magnetic resonance imaging. Ann N Y Acad Sci 2018; 1451:42-70. [PMID: 30426517 DOI: 10.1111/nyas.13990] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 10/13/2018] [Accepted: 10/19/2018] [Indexed: 12/28/2022]
Abstract
Cannabis use is becoming increasingly popular as a growing number of states pass legislation to legalize cannabis and cannabis-derived products for recreational and/or medical purposes. Given the widespread use of cannabis, it is critical to understand the neural consequences related to cannabis use. In this review, we focus on evidence from functional magnetic resonance imaging studies that document acute and residual alterations in brain function during tasks spanning a variety of cognitive domains: executive function, attention and working memory, memory, motor skills, error monitoring, and reward and affective processing. Although it is clear that cannabis affects brain function, the findings are somewhat inconsistent; variables that potentially affect study outcomes are outlined, including a discussion of the impact of chronological age and age of cannabis onset as well as length of abstinence at the time of assessment, which are important considerations when measuring cannabis use patterns. Inherent differences between recreational/adult cannabis use versus use for medical purposes are also discussed, given their importance to public policy decisions.
Collapse
Affiliation(s)
- Kelly A Sagar
- Cognitive and Clinical Neuroimaging Core, McLean Hospital, Belmont, Massachusetts.,Department of Psychiatry, Harvard Medical School, Boston, Massachusetts.,Boston University School of Medicine, Boston, Massachusetts
| | - Staci A Gruber
- Cognitive and Clinical Neuroimaging Core, McLean Hospital, Belmont, Massachusetts.,Department of Psychiatry, Harvard Medical School, Boston, Massachusetts
| |
Collapse
|
36
|
Sagar KA, Gruber SA. Marijuana matters: reviewing the impact of marijuana on cognition, brain structure and function, & exploring policy implications and barriers to research. Int Rev Psychiatry 2018; 30:251-267. [PMID: 29966459 PMCID: PMC6455965 DOI: 10.1080/09540261.2018.1460334] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The neurobiologic effects of cannabis, commonly referred to as 'marijuana' (MJ), have been studied for decades. The impact of recreational MJ use on cognition and measures of brain function and structure is outlined, and variables influencing study results are discussed, including age of the consumer, patterns of MJ use, variations in MJ potency, and the presence of additional cannabinoids. Although evidence suggests that chronic, heavy recreational MJ use is related to cognitive decrements and neural changes, particularly when use begins in adolescence, findings from studies of recreational MJ users may not be applicable to medical marijuana (MMJ) patients given differences in demographic variables, product selection, and reasons for use. Although additional research is needed to fully understand the impact of MJ and individual cannabinoids on the brain, current findings are beginning to inform public policy, including considerations for age limits, potential limits for some cannabinoids, and guidelines for use. However, barriers continue to impede researchers' ability to conduct studies that will guide policy change and provide vital information to consumers and patients regarding best practices and safest methods for use. The need for information is critical, as legalization of MJ for medical and recreational use is increasingly widespread.
Collapse
Affiliation(s)
- Kelly A. Sagar
- McLean Hospital, Cognitive and Clinical Neuroimaging Core, McLean Imaging Center, 115 Mill St, Belmont, MA, 02478,Department of Psychiatry, Harvard Medical School, 401 Park Drive, Boston, MA, 02115,Boston University School of Medicine, 72 E Concord St Boston, MA, 02118
| | - Staci A. Gruber
- McLean Hospital, Cognitive and Clinical Neuroimaging Core, McLean Imaging Center, 115 Mill St, Belmont, MA, 02478,Department of Psychiatry, Harvard Medical School, 401 Park Drive, Boston, MA, 02115,Corresponding Author Information Address: McLean Hospital, 115 Mill Street, Belmont, MA 02478, Telephone: 617-855-2762, Fax: 617-855-3713,
| |
Collapse
|
37
|
The effect of interactions between genetics and cannabis use on neurocognition. A review. Prog Neuropsychopharmacol Biol Psychiatry 2018; 82:95-106. [PMID: 29191570 DOI: 10.1016/j.pnpbp.2017.11.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 11/22/2017] [Accepted: 11/27/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND Cannabis is one of the most widely-used drugs in industrialized countries. It is now well established that cannabis use impacts neurocognition. In the intoxication period time episodic memory, working memory and attention are impacted and impulsivity is increased. The long-term effects of cannabis use tend to be similar. Various internal factors, such as sex differences, modulate this impact. It is unclear whether genetic variations can also influence the impact of cannabis on neurocognition. We set out to examine the impact of genetic variations on neurocognition in cannabis users. METHOD We conducted a search via the PubMed, Web of Science, and ScienceDirect databases to identify studies measuring neurocognition and assessing genotypes in the context of cannabis use. RESULTS We included 13 articles. We found that working memory, verbal and visual memory and sustained attention are more impacted during intoxication in subjects with the Val COMT allele. COMT gene could also modulate sustained attention in regular use. The CNR1, AKT1, DBH and 5-HTT/SLC6A4 genes may also modulate effects. CONCLUSION Most of these genes are linked to schizophrenia. A fuller understanding of their impact on the effects of cannabis on neurocognition would thus help elucidate the mechanisms linking cannabis and psychosis. However, evidence is still scant, and more research is needed.
Collapse
|
38
|
Meier MH, Caspi A, Danese A, Fisher HL, Houts R, Arseneault L, Moffitt TE. Associations between adolescent cannabis use and neuropsychological decline: a longitudinal co-twin control study. Addiction 2018; 113:257-265. [PMID: 28734078 PMCID: PMC5760333 DOI: 10.1111/add.13946] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 06/21/2017] [Accepted: 07/18/2017] [Indexed: 01/17/2023]
Abstract
AIMS This study tested whether adolescents who used cannabis or met criteria for cannabis dependence showed neuropsychological impairment prior to cannabis initiation and neuropsychological decline from before to after cannabis initiation. DESIGN A longitudinal co-twin control study. SETTING AND PARTICIPANTS Participants were 1989 twins from the Environmental Risk (E-Risk) Longitudinal Twin Study, a nationally representative birth cohort of twins born in England and Wales from 1994 to 1995. MEASUREMENTS Frequency of cannabis use and cannabis dependence were assessed at age 18. Intelligence quotient (IQ) was obtained at ages 5, 12 and 18. Executive functions were assessed at age 18. FINDINGS Compared with adolescents who did not use cannabis, adolescents who used cannabis had lower IQ in childhood prior to cannabis initiation and lower IQ at age 18, but there was little evidence that cannabis use was associated with IQ decline from ages 12-18. For example, adolescents with cannabis dependence had age 12 and age 18 IQ scores that were 5.61 (t = -3.11, P = 0.002) and 7.34 IQ points (t = -5.27, P < 0.001) lower than adolescents without cannabis dependence, but adolescents with cannabis dependence did not show greater IQ decline from age 12-18 (t = -1.27, P = 0.20). Moreover, adolescents who used cannabis had poorer executive functions at age 18 than adolescents who did not use cannabis, but these associations were generally not apparent within twin pairs. For example, twins who used cannabis more frequently than their co-twin performed similarly to their co-twin on five of six executive function tests (Ps > 0.10). The one exception was that twins who used cannabis more frequently than their co-twin performed worse on one working memory test (Spatial Span reversed; β = -0.07, P = 0.036). CONCLUSIONS Short-term cannabis use in adolescence does not appear to cause IQ decline or impair executive functions, even when cannabis use reaches the level of dependence. Family background factors explain why adolescent cannabis users perform worse on IQ and executive function tests.
Collapse
Affiliation(s)
| | - Avshalom Caspi
- Department of Psychology and Neuroscience, Duke University, Durham, NC, USA,Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA,Medical Research Council Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, UK
| | - Andrea Danese
- Medical Research Council Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, UK,Department of Child and Adolescent Psychiatry, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, UK,National and Specialist Service Foundation Trust, London, UK
| | - Helen L. Fisher
- Medical Research Council Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, UK
| | - Renate Houts
- Department of Psychology and Neuroscience, Duke University, Durham, NC, USA,Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
| | - Louise Arseneault
- Medical Research Council Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, UK
| | - Terrie E. Moffitt
- Department of Psychology and Neuroscience, Duke University, Durham, NC, USA,Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA,Medical Research Council Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, UK
| |
Collapse
|
39
|
Mokrysz C, Freeman TP. Commentary on Meier et al. (2018): Smoke and mirrors-are adolescent cannabis users vulnerable to cognitive impairment? Addiction 2018; 113:266-267. [PMID: 29314408 DOI: 10.1111/add.14055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 09/29/2017] [Indexed: 01/20/2023]
Affiliation(s)
- Claire Mokrysz
- Clinical Educational and Health Psychology, University College London, London, UK
| | - Tom P Freeman
- Clinical Educational and Health Psychology, University College London, London, UK
- National Addiction Centre, Institute of Psychiatry, Psychology and Neuroscience, Kings College London, London, UK
| |
Collapse
|
40
|
Adolescent cannabinoid exposure effects on natural reward seeking and learning in rats. Psychopharmacology (Berl) 2018; 235:121-134. [PMID: 29022083 PMCID: PMC5790819 DOI: 10.1007/s00213-017-4749-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 09/19/2017] [Indexed: 02/06/2023]
Abstract
RATIONALE Adolescence is characterized by endocannabinoid (ECB)-dependent refinement of neural circuits underlying emotion, learning, and motivation. As a result, adolescent cannabinoid receptor stimulation (ACRS) with phytocannabinoids or synthetic agonists like "Spice" cause robust and persistent changes in both behavior and circuit architecture in rodents, including in reward-related regions like medial prefrontal cortex and nucleus accumbens (NAc). OBJECTIVES AND METHODS Here, we examine persistent effects of ACRS with the cannabinoid receptor 1/2 specific agonist WIN55-212,2 (WIN; 1.2 mg/kg/day, postnatal day (PD) 30-43), on natural reward-seeking behaviors and ECB system function in adult male Long Evans rats (PD 60+). RESULTS WIN ACRS increased palatable food intake, and altered attribution of incentive salience to food cues in a sign-/goal-tracking paradigm. ACRS also blunted hunger-induced sucrose intake, and resulted in increased anandamide and oleoylethanolamide levels in NAc after acute food restriction not seen in controls. ACRS did not affect food neophobia or locomotor response to a novel environment, but did increase preference for exploring a novel environment. CONCLUSIONS These results demonstrate that ACRS causes long-term increases in natural reward-seeking behaviors and ECB system function that persist into adulthood, potentially increasing liability to excessive natural reward seeking later in life.
Collapse
|
41
|
Braatveit KJ, Torsheim T, Hove O. Intellectual Functioning in In-Patients with Substance Use Disorders: Preliminary Results from a Clinical Mediation Study of Factors Contributing to IQ Variance. Eur Addict Res 2018; 24:19-27. [PMID: 29393174 DOI: 10.1159/000486620] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 12/29/2017] [Indexed: 11/19/2022]
Abstract
AIMS To investigate the direct effect of different childhood difficulties on adult intelligence coefficient (IQ) and their possible indirect effect through the mediating pathways of education and severity substance use. PARTICIPANTS Ninety in-patients aged 19-64. The participants had abstained from substance use for at least 6 weeks and had different substance use profiles. MEASUREMENTS Substance use disorder (SUD) and psychiatric illnesses were diagnosed according to the International Classification of Diseases 10th edition criteria. IQ was measured with the Wechsler Adult Intelligence Scale, 4th edition. Childhood difficulties, severity of substance use and level of education were assessed through a self-report questionnaire. FINDINGS Mean full scale IQ for the studied population was 87.3. Learning and attention deficit/hyperactivity difficulties in childhood were directly related to adult IQ. Education had a mediating effect between childhood learning difficulties/conduct problems and the verbal comprehension index. There was no significant difference in IQ due to the specific substance used or severity of substance use. CONCLUSION IQ variance in in-treatment individuals with SUD was related to childhood functioning alone or through the mediator of education. Substance-related factors did not contribute to IQ variance. The results fit a normal theory of IQ development with commonly known risk factors and no disturbing effect of substance use.
Collapse
Affiliation(s)
| | - Torbjørn Torsheim
- Department of Psychosocial Science, University of Bergen, Faculty of Psychology, Bergen, Norway
| | - Oddbjørn Hove
- Department of Research and Innovation, Helse Fonna HF, Haugesund, Norway
| |
Collapse
|
42
|
Boggs DL, Nguyen JD, Morgenson D, Taffe MA, Ranganathan M. Clinical and Preclinical Evidence for Functional Interactions of Cannabidiol and Δ 9-Tetrahydrocannabinol. Neuropsychopharmacology 2018; 43:142-154. [PMID: 28875990 PMCID: PMC5719112 DOI: 10.1038/npp.2017.209] [Citation(s) in RCA: 146] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 08/30/2017] [Accepted: 08/31/2017] [Indexed: 12/21/2022]
Abstract
The plant Cannabis sativa, commonly called cannabis or marijuana, has been used for its psychotropic and mind-altering side effects for millennia. There has been growing attention in recent years on its potential therapeutic efficacy as municipalities and legislative bodies in the United States, Canada, and other countries grapple with enacting policy to facilitate the use of cannabis or its constituents for medical purposes. There are >550 chemical compounds and >100 phytocannabinoids isolated from cannabis, including Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is thought to produce the main psychoactive effects of cannabis, while CBD does not appear to have similar effects. Studies conflict as to whether CBD attenuates or exacerbates the behavioral and cognitive effects of THC. This includes effects of CBD on THC-induced anxiety, psychosis, and cognitive deficits. In this article, we review the available evidence on the pharmacology and behavioral interactions of THC and CBD from preclinical and human studies, particularly with reference to anxiety and psychosis-like symptoms. Both THC and CBD, as well as other cannabinoid molecules, are currently being evaluated for medicinal purposes, separately and in combination. Future cannabis-related policy decisions should include consideration of scientific findings, including the individual and interactive effects of CBD and THC.
Collapse
Affiliation(s)
- Douglas L Boggs
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA,VA Connecticut Healthcare System, West Haven, CT, USA
| | - Jacques D Nguyen
- Department of Neuroscience; The Scripps Research Institute, La Jolla, CA, USA
| | | | - Michael A Taffe
- Department of Neuroscience; The Scripps Research Institute, La Jolla, CA, USA
| | - Mohini Ranganathan
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA,VA Connecticut Healthcare System, West Haven, CT, USA,Department of Psychiatry, Yale University School of Medicine, 950 Campbell Avenue, New Haven, CT 06511, USA, Tel: +1 203 932 5711X2546, E-mail:
| |
Collapse
|
43
|
Drug law reform, performativity and the politics of childhood. THE INTERNATIONAL JOURNAL OF DRUG POLICY 2017; 51:56-66. [PMID: 29202316 DOI: 10.1016/j.drugpo.2017.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 04/10/2017] [Accepted: 10/06/2017] [Indexed: 11/21/2022]
Abstract
Children are critical to debates about drug law reform. For both advocates of liberalisation and, especially, defenders of prohibition, the protection of children is an important rhetorical device in pressing for, or resisting, change. However, the privileged position of minors within such discussions, or talk about drugs in general, has rarely been explored in any depth in either drug and alcohol studies or legal research. Drawing on scholarship on performativity, and particularly John Law's work on 'collateral realities', this article will consider how constructs such as childhood and drugs are 'produced' and '(re)made' in such discourses. Through analysis of legal measures, policy documents/statements submitted to the UN General Assembly Special Session on Drugs (UNGASS) in 2016, and scientific discussion, it will be argued that such 'realities' include the constitution of the child as the logical victim of drugs (and the natural beneficiary or casualty of reform), and the enactment of drugs as an inherent threat to children. It is suggested that drug policy research needs to pay attention to age as a social construct and cultural category, and that a critical awareness of the relevance of age in policy discourse is as necessary as, for example, race, class or gender. Moreover, attendance to the ontological politics of constructs such as 'childhood' and 'drugs' is important if law and policy measures are to account for young people's agency.
Collapse
|
44
|
Castellanos-Ryan N, Pingault JB, Parent S, Vitaro F, Tremblay RE, Séguin JR. Adolescent cannabis use, change in neurocognitive function, and high-school graduation: A longitudinal study from early adolescence to young adulthood. Dev Psychopathol 2017; 29:1253-1266. [PMID: 28031069 PMCID: PMC5403347 DOI: 10.1017/s0954579416001280] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The main objective of this prospective longitudinal study was to investigate bidirectional associations between adolescent cannabis use (CU) and neurocognitive performance in a community sample of 294 young men from ages 13 to 20 years. The results showed that in early adolescence, and prior to initiation to CU, poor short-term and working memory, but high verbal IQ, were associated with earlier age of onset of CU. In turn, age of CU onset and CU frequency across adolescence were associated with (a) specific neurocognitive decline in verbal IQ and executive function tasks tapping trial and error learning and reward processing by early adulthood and (b) lower rates of high-school graduation. The association between CU onset and change in neurocognitive function, however, was found to be accounted for by CU frequency. Whereas the link between CU frequency across adolescence and change in verbal IQ was explained (mediated) by high school graduation, the link between CU frequency and tasks tapping trial and error learning were independent from high school graduation, concurrent cannabis and other substance use, adolescent alcohol use, and externalizing behaviors. Findings support prevention efforts aimed at delaying onset and reducing frequency of CU.
Collapse
|
45
|
Does Cannabis Use Cause Declines in Neuropsychological Functioning? A Review of Longitudinal Studies. J Int Neuropsychol Soc 2017; 23:893-902. [PMID: 29198276 PMCID: PMC8100918 DOI: 10.1017/s1355617717000789] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Cannabis use has been linked to impairments in neuropsychological functioning across a large and continually expanding body of research. Yet insight into underlying causal relations remains limited due to the historically cross-sectional nature of studies in this area. Recently, however, studies have begun to use more informative design strategies to delineate these associations. The aim of this article is to provide a critical evaluation and review of research that uses longitudinal designs to examine the link between cannabis use and neuropsychological functioning. In summarizing the primary findings across these studies, this review suggests that cannabis use leads to neuropsychological decline. However, across most studies, these associations were modest, were present only for the group with the heaviest cannabis use, and were often attenuated (or no longer significant) after controlling for potential confounding variables. Future studies with neuropsychological data before and after initiation of cannabis use, along with careful measurement and control of "shared risk factors" between cannabis use and poorer neuropsychological outcomes, are needed to better understand who, and under what conditions, is most vulnerable to cannabis-associated neuropsychological decline. (JINS, 2017, 23, 893-902).
Collapse
|
46
|
Guttmannova K, Kosterman R, White HR, Bailey JA, Lee JO, Epstein M, Jones TM, Hawkins JD. The association between regular marijuana use and adult mental health outcomes. Drug Alcohol Depend 2017; 179:109-116. [PMID: 28763778 PMCID: PMC5599346 DOI: 10.1016/j.drugalcdep.2017.06.016] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 06/10/2017] [Accepted: 06/11/2017] [Indexed: 12/23/2022]
Abstract
OBJECTIVE The present study is a prospective examination of the relationship between regular marijuana use from adolescence through young adulthood and mental health outcomes at age 33. METHODS Data came from a gender-balanced, ethnically diverse longitudinal panel of 808 participants from Seattle, Washington. Outcomes included symptom counts for six mental health disorders. Regular marijuana use was tracked during adolescence and young adulthood. Regression analyses controlled for demographics and early environment, behaviors, and individual risk factors. RESULTS Nonusers of marijuana reported fewer symptoms of alcohol use disorder, nicotine dependence, and generalized anxiety disorder than any category of marijuana users. More persistent regular marijuana use in young adulthood was positively related to more symptoms of cannabis use disorder, alcohol use disorder, and nicotine dependence at age 33. CONCLUSIONS Findings highlight the importance of avoiding regular marijuana use, especially chronic use in young adulthood. Comprehensive prevention and intervention efforts focusing on marijuana and other substance use might be particularly important in the context of recent legalization of recreational marijuana use in Washington and other U.S. states.
Collapse
Affiliation(s)
- Katarina Guttmannova
- Center for the Study of Health and Risk Behaviors, Department of Psychiatry and Behavioral Sciences, School of Medicine, University of Washington, Box 354944, Seattle, WA 98195-4944, USA.
| | - Rick Kosterman
- Social Development Research Group, School of Social Work, University of Washington, 9725 3rd Ave NE, Suite 401, Seattle, WA 98115, USA.
| | - Helene R White
- Center of Alcohol Studies, Rutgers - The State University of New Jersey, 607 Allison Rd., Piscataway, NJ 08854, USA.
| | - Jennifer A Bailey
- Social Development Research Group, School of Social Work, University of Washington, 9725 3rd Ave NE, Suite 401, Seattle, WA 98115, USA.
| | - Jungeun Olivia Lee
- School of Social Work, University of Southern California, 1150 S. Olive Street, Suite 1400, Los Angeles, CA 90015, USA.
| | - Marina Epstein
- Social Development Research Group, School of Social Work, University of Washington, 9725 3rd Ave NE, Suite 401, Seattle, WA 98115, USA.
| | - Tiffany M Jones
- Social Development Research Group, School of Social Work, University of Washington, 9725 3rd Ave NE, Suite 401, Seattle, WA 98115, USA.
| | - J David Hawkins
- Social Development Research Group, School of Social Work, University of Washington, 9725 3rd Ave NE, Suite 401, Seattle, WA 98115, USA.
| |
Collapse
|
47
|
The utility of twins in developmental cognitive neuroscience research: How twins strengthen the ABCD research design. Dev Cogn Neurosci 2017; 32:30-42. [PMID: 29107609 PMCID: PMC5847422 DOI: 10.1016/j.dcn.2017.09.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 08/31/2017] [Accepted: 09/05/2017] [Indexed: 02/01/2023] Open
Abstract
The ABCD twin study will elucidate the genetic and environmental contributions to a wide range of mental and physical health outcomes in children, including substance use, brain and behavioral development, and their interrelationship. Comparisons within and between monozygotic and dizygotic twin pairs, further powered by multiple assessments, provide information about genetic and environmental contributions to developmental associations, and enable stronger tests of causal hypotheses, than do comparisons involving unrelated children. Thus a sub-study of 800 pairs of same-sex twins was embedded within the overall Adolescent Brain and Cognitive Development (ABCD) design. The ABCD Twin Hub comprises four leading centers for twin research in Minnesota, Colorado, Virginia, and Missouri. Each site is enrolling 200 twin pairs, as well as singletons. The twins are recruited from registries of all twin births in each State during 2006-2008. Singletons at each site are recruited following the same school-based procedures as the rest of the ABCD study. This paper describes the background and rationale for the ABCD twin study, the ascertainment of twin pairs and implementation strategy at each site, and the details of the proposed analytic strategies to quantify genetic and environmental influences and test hypotheses critical to the aims of the ABCD study.
Collapse
|
48
|
Boccio CM, Beaver KM. Examining the influence of adolescent marijuana use on adult intelligence: Further evidence in the causation versus spuriousness debate. Drug Alcohol Depend 2017; 177:199-206. [PMID: 28609722 DOI: 10.1016/j.drugalcdep.2017.04.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 04/04/2017] [Accepted: 04/06/2017] [Indexed: 11/26/2022]
Abstract
OBJECTIVES There is conflicting evidence regarding the association between adolescent marijuana use and adult intelligence, with some studies suggesting adolescent marijuana use can lead to declines in intelligence. The purpose of this study is to shed additional light on the potential link between marijuana use and changes in intelligence. METHODS We employed change scores and ordinary least squares (OLS) analysis to test for associations between marijuana use and changes in intelligence scores from adolescence (ages 12-21) to adulthood (ages 18-26) using data drawn from the National Longitudinal Study of Adolescent to Adult Health. RESULTS The findings revealed that while a binary measure of marijuana use (ever/never) maintains a statistically significant association with changes in intelligence scores, the effect sizes are relatively small (β=0.043-0.051). Additionally, our findings did not reveal a significant association between cumulative marijuana use and changes in intelligence scores. CONCLUSIONS Taken together, the results suggest that while the binary measure of marijuana use (ever/never) has a statistically significant association with changes in intelligence scores, the binary measure accounts for at most a 1-2 point change in intelligence scores.
Collapse
Affiliation(s)
- Cashen M Boccio
- College of Criminology and Criminal Justice, Florida State University, 145 Convocation Way, Eppes Hall, Tallahassee, FL 32306-1127, United States.
| | - Kevin M Beaver
- College of Criminology and Criminal Justice, Florida State University, 145 Convocation Way, Eppes Hall, Tallahassee, FL 32306-1127, United States; Center for Social and Humanities Research, King Abdulaziz University, Jeddah, Saudi Arabia.
| |
Collapse
|
49
|
Englund A, Freeman TP, Murray RM, McGuire P. Can we make cannabis safer? Lancet Psychiatry 2017; 4:643-648. [PMID: 28259650 DOI: 10.1016/s2215-0366(17)30075-5] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 10/10/2016] [Accepted: 11/09/2016] [Indexed: 12/15/2022]
Abstract
Cannabis use and related problems are on the rise globally alongside an increase in the potency of cannabis sold on both black and legal markets. Additionally, there has been a shift towards abandoning prohibition for a less punitive and more permissive legal stance on cannabis, such as decriminalisation and legalisation. It is therefore crucial that we explore new and innovative ways to reduce harm. Research has found cannabis with high concentrations of its main active ingredient, δ-9-tetrahydrocannabinol (THC), to be more harmful (in terms of causing the main risks associated with cannabis use, such as addiction, psychosis, and cognitive impairment) than cannabis with lower concentrations of THC. By contrast, cannabidiol, which is a non-intoxicating and potentially therapeutic component of cannabis, has been found to reduce the negative effects of cannabis use. Here, we briefly review findings from studies investigating various types of cannabis and discuss how future research can help to better understand and reduce the risks of cannabis use.
Collapse
Affiliation(s)
- Amir Englund
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
| | - Tom P Freeman
- Clinical Psychopharmacology Unit, University College London, London, UK
| | - Robin M Murray
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Philip McGuire
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| |
Collapse
|
50
|
Kirschmann EK, McCalley DM, Edwards CM, Torregrossa MM. Consequences of Adolescent Exposure to the Cannabinoid Receptor Agonist WIN55,212-2 on Working Memory in Female Rats. Front Behav Neurosci 2017; 11:137. [PMID: 28785210 PMCID: PMC5519521 DOI: 10.3389/fnbeh.2017.00137] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 07/07/2017] [Indexed: 11/13/2022] Open
Abstract
Marijuana is a prevalent illicit substance used by adolescents, and several studies have indicated that adolescent use can lead to long-term cognitive deficits including problems with attention and memory. However, preclinical animal studies that observe cognitive deficits after cannabinoid exposure during adolescence utilize experimenter administration of doses of cannabinoids that may exceed what an organism would choose to take, suggesting that contingency and dose are critical factors that need to be addressed in translational models of consequences of cannabinoid exposure. Indeed, we recently developed an adolescent cannabinoid self-administration paradigm in male rats, and found that prior adolescent self-administration of the cannabinoid receptor agonist WIN55,212-2 (WIN) resulted in improved working memory performance in adulthood. In addition, the doses self-administered were not as high as those that are found to produce memory deficits. However, given known sex differences in both drug self-administration and learning and memory processes, it is possible that cannabinoid self-administration could have different cognitive consequences in females. Therefore, we aimed to explore the effects of self-administered vs. experimenter-administered WIN in adolescent female rats on adult cognitive function. Female rats were trained to self-administer WIN daily throughout adolescence (postnatal day 34–59). A control group self-administered vehicle solution. The acute effects of adolescent WIN self-administration on memory were determined using a short-term spatial memory test 24 h after final SA session; and the long-term effects on cognitive performance were assessed during protracted abstinence in adulthood using a delayed-match-to-sample working memory task. In a separate experiment, females were given daily intraperitoneal (IP) injections of a low or high dose of WIN, corresponding to self-administered and typical experimenter-administered doses, respectively, or its vehicle during adolescence and working memory was assessed under drug-free conditions in adulthood. While self-administration of WIN in adolescence had no significant effects on short-term spatial memory or adult working memory, experimenter administration of WIN resulted in improved adult working memory performance that was more pronounced in the low dose group. Thus, low-dose adolescent WIN exposure, whether self-administered or experimenter-administered, results in either improvements or no change in adult working memory performance in female rats, similar to previous results found in males.
Collapse
Affiliation(s)
- Erin K Kirschmann
- Department of Psychiatry, Translational Neuroscience Program, University of PittsburghPittsburgh, PA, United States
| | - Daniel M McCalley
- Department of Psychiatry, Translational Neuroscience Program, University of PittsburghPittsburgh, PA, United States
| | - Caitlyn M Edwards
- Department of Psychiatry, Translational Neuroscience Program, University of PittsburghPittsburgh, PA, United States.,Center for Neuroscience, University of PittsburghPittsburgh, PA, United States
| | - Mary M Torregrossa
- Department of Psychiatry, Translational Neuroscience Program, University of PittsburghPittsburgh, PA, United States.,Center for Neuroscience, University of PittsburghPittsburgh, PA, United States
| |
Collapse
|