EXPERT REACTION: Smoking dope just once as a teen could change your brain
Embargoed until:
Publicly released:
2019-01-15 05:00
Teens who say they have only smoked cannabis once or twice have both structural and cognitive changes in their brains, compared with teens who have never smoked dope, according to a small Australian-led study. The researchers used brain scans of 46 14-year-olds and found a greater volume of grey matter in some brain regions among the teens with just one or two instances of cannabis use compared with those who had never tried the drug. The researchers also found a link between these changes in grey matter and assessments of reasoning and anxiety.
Journal/conference: JNeurosci
Link to research (DOI): 10.1523/JNEUROSCI.3375-17.2018
Organisation/s: Swinburne University of Technology
Funder: This work received support from the following sources: the European Union-funded FP6 Integrated Project IMAGEN (Reinforcement-related behaviour in normal brain function and psychopathology) (LSHM-CT-2007-037286), the Horizon 2020 funded ERC Advanced Grant ‘STRATIFY' (Brain network based stratification of reinforcement-related disorders) (695313), ERANID (Understanding the Interplay between Cultural, Biological and Subjective Factors in Drug Use Pathways) (PR-ST-0416-10004), BRIDGET (JPND: BRain Imaging, cognition Dementia and next generation GEnomics) (MR/N027558/1), the FP7 projects IMAGEMEND(602450; IMAging GEnetics for MENtal Disorders) and MATRICS (603016), the Innovative Medicine Initiative Project EUAIMS (115300-2), the Medical Research Council Grant 'c-VEDA' (Consortium on Vulnerability to Externalizing Disorders and Addictions) (MR/N000390/1), the Swedish Research Council FORMAS, the Medical Research
Council, the National Institute for Health Research (NIHR) Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King's College London, the Bundesministeriumfür Bildung und Forschung (BMBF grants 01GS08152; 01EV0711; eMED SysAlc01ZX1311A; Forschungsnetz AERIAL), the Deutsche Forschungsgemeinschaft (DFG grants SM 80/7-1, SM 80/7-2, SFB 940/1), and the Fondation pour la Recherche Médicale (DPA20140629802), the Fondation de l'Avenir. Further support was provided by grants from: ANR (project AF12-NEUR0008-01 - WM2NA, and ANR-12-SAMA-0004), the Fondation de France, the Fondation pour la Recherche Médicale, the Mission Interministérielle de Lutte-contre-les-Drogues-et-les- Conduites-Addictives (MILDECA), the Assistance-Publique-Hôpitaux-de-Paris and INSERM (interface grant), Paris Sud University IDEX 2012; the National Institutes of Health, Science Foundation Ireland (16/ERCD/3797),
U.S.A. (Axon, Testosterone and Mental Health during Adolescence; RO1 MH085772-01A1), and by NIH Consortium grant U54 EB020403, supported by a cross-NIH alliance that funds Big Data to Knowledge Centres of Excellence. RR is supported by Dana Foundation David Mahoney program and CTSA Grant Number UL1 TR001863 from the National Center for Advancing Translational Science (NCATS), components of the National Institutes of Health (NIH), and NIH roadmap for Medical Research.
Media Release
From: Society for Neuroscience
A Little Weed Can Change the Teenage Brain
Teenagers who report using recreational marijuana just once or twice display increased volume of numerous brain regions, according to a study of 14-year-olds from Ireland, England, France, and Germany. The research, published in JNeurosci, warrants further study of low-level cannabis use among adolescents amid changing societal attitudes toward the drug.
Analyzing data from a large research program investigating adolescent brain development and mental health, Catherine Orr and colleagues identified brain regions rich in cannabinoid receptors that underwent structural changes in teenagers who reported limited cannabis use. These differences persisted despite controlling for many variables, including sex and socioeconomic status as well as alcohol and nicotine use, and were only apparent after cannabis use. Finally, the researchers demonstrate associations between increased grey matter volume in low-level cannabis users and assessments of reasoning and anxiety.
Given the important role of the endogenous cannabinoid system in brain development during adolescence, teenagers may be particularly vulnerable to the effects of THC, the primary psychoactive component of marijuana. Additional research is needed to determine whether these findings apply to more diverse populations beyond the four European countries studied here.
Attachments:
Note: Not all attachments are visible to the general public
-
Society for Neuroscience
Web page
Expert Reaction
These comments have been collated by the Science Media Centre to provide a variety of expert perspectives on this issue. Feel free to use these quotes in your stories. Views expressed are the personal opinions of the experts named. They do not represent the views of the SMC or any other organisation unless specifically stated.
Professor Darryl Eyles is Director of the Neurobiology Laboratory at the Queensland Brain Institute, University of Queensland