title: Daily marijuana use is not associated with brain morphometric measures in adolescents or adults.
abstract: Recent research has suggested that marijuana use is associated with volumetric and shape differences in subcortical structures, including the nucleus accumbens and amygdala, in a dose-dependent fashion. Replication of such results in well controlled studies is essential to clarify the effects of marijuana. To that end, this retrospective study examined brain morphology in a sample of adult daily marijuana users (n = 29) versus nonusers (n = 29) and a sample of adolescent daily users (n = 50) versus nonusers (n = 50). Groups were matched on a critical confounding variable, alcohol use, to a far greater degree than in previously published studies. We acquired high-resolution MRI scans, and investigated group differences in gray matter using voxel-based morphometry, surface-based morphometry, and shape analysis in structures suggested to be associated with marijuana use, as follows: the nucleus accumbens, amygdala, hippocampus, and cerebellum. No statistically significant differences were found between daily users and nonusers on volume or shape in the regions of interest. Effect sizes suggest that the failure to find differences was not due to a lack of statistical power, but rather was due to the lack of even a modest effect. In sum, the results indicate that, when carefully controlling for alcohol use, gender, age, and other variables, there is no association between marijuana use and standard volumetric or shape measurements of subcortical structures.
authors: Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, and barbara.weiland@colorado.edu.
authors: Barbara J
authors: http://orcid.org/0000-0002-4453-2872
authors: BJ
authors: Weiland
authors: Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, and.
authors: Rachel E
authors: RE
authors: Thayer
authors: Department of Psychological and Brain Sciences, University of Louisville, Louisville, Kentucky 40292.
authors: Brendan E
authors: http://orcid.org/0000-0001-6665-5833
authors: BE
authors: Depue
authors: Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, and.
authors: Amithrupa
authors: A
authors: Sabbineni
authors: Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, and.
authors: Angela D
authors: AD
authors: Bryan
authors: Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, and.
authors: Kent E
authors: KE
authors: Hutchison
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging; D001921:Brain / Q000473:pathology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008385:Marijuana Smoking / Q000473:pathology*; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D055815:Young Adult
keywords: MRI; gray matter; marijuana; morphology
references: J Neurol Sci. 1986 Dec;76(2-3):283-94
references: 3794753
references: Curr Pharm Des. 2014;20(13):2138-67
references: 23829361
references: Am J Addict. 2005 Jan-Feb;14(1):64-72
references: 15804878
references: Am J Psychiatry. 2001 Feb;158(2):198-204
references: 11156801
references: Arch Gen Psychiatry. 2000 Sep;57(9):894-902
references: 10986553
references: Alcohol Alcohol. 2009 Mar-Apr;44(2):136-40
references: 19147798
references: J Abnorm Psychol. 2001 Feb;110(1):40-8
references: 11261398
references: Alcohol Clin Exp Res. 2014 Mar;38(3):739-48
references: 24483366
references: Proc Natl Acad Sci U S A. 2014 Nov 25;111(47):16913-8
references: 25385625
references: Neuroimage. 2009 Mar;45(1 Suppl):S173-86
references: 19059349
references: Neurotoxicol Teratol. 2007 Jan-Feb;29(1):141-52
references: 17169528
references: Proc Natl Acad Sci U S A. 2012 Oct 2;109(40):E2657-64
references: 22927402
references: Alcohol Clin Exp Res. 1992 Dec;16(6):1078-89
references: 1471762
references: Neuropsychopharmacology. 2012 Oct;37(11):2368-76
references: 22669173
references: Hum Brain Mapp. 2014 Oct;35(10):4965-78
references: 24753006
references: Alcohol Clin Exp Res. 1991 Jun;15(3):418-27
references: 1877728
references: J Consult Clin Psychol. 1988 Dec;56(6):893-7
references: 3204199
references: J AIDS Clin Res. 2013 Jun 23;4(6):217
references: 25126447
references: Neuropsychopharmacology. 2011 Sep;36(10):2086-96
references: 21677649
references: Front Psychiatry. 2013 Oct 16;4:130
references: 24137134
references: Neuroimage. 2006 Sep;32(3):1465-71
references: 16872844
references: Alcohol Clin Exp Res. 2011 Jun;35(6):1187-200
references: 21410483
references: Psychol Med. 2011 Nov;41(11):2349-59
references: 21466751
references: Psychiatry Res. 2010 May 30;182(2):152-9
references: 20413277
references: Neuroimage. 2001 Jul;14(1 Pt 1):21-36
references: 11525331
references: Neuroimage. 2004;23 Suppl 1:S69-84
references: 15501102
references: Neuropsychol Rev. 2013 Jun;23(2):117-37
references: 23129391
references: Curr Pharm Des. 2012;18(32):5015-23
references: 22716139
references: Neuroimage. 2012 Feb 15;59(4):3845-51
references: 21982932
references: Drug Alcohol Depend. 2014 Apr 1;137:68-75
references: 24513182
references: Drug Alcohol Depend. 2011 Apr 1;114(2-3):242-5
references: 21050680
references: Neuropsychol Rev. 2007 Sep;17(3):235-8
references: 17680366
references: Biol Psychiatry. 2008 Aug 1;64(3):192-202
references: 18374900
references: Clin Pharmacol Ther. 2007 Nov;82(5):572-8
references: 17429350
references: Neuroreport. 2000 Feb 28;11(3):491-6
references: 10718301
references: Arch Gen Psychiatry. 1961 Jun;4:561-71
references: 13688369
references: Curr Addict Rep. 2014 Jun 1;1(2):144-156
references: 25013751
references: Addiction. 1993 Jun;88(6):791-804
references: 8329970
references: Psychopharmacology (Berl). 2012 Apr;220(3):529-39
references: 21952669
references: Neuropsychopharmacology. 2014 Aug;39(9):2041-8
references: 24633558
references: Psychiatry Res. 2005 Aug 30;139(3):181-90
references: 16054344
references: Hippocampus. 2012 Apr;22(4):651-5
references: 21656873
references: J Child Psychol Psychiatry. 2007 Jun;48(6):592-600
references: 17537075
references: J Neurosci. 2014 Apr 16;34(16):5529-38
references: 24741043
references: Neuroimage. 2002 Apr;15(4):870-8
references: 11906227
references: Arch Neurol. 2008 Oct;65(10):1363-7
references: 18852353
references: Psychopharmacology (Berl). 2006 Nov;188(4):425-44
references: 17019571
references: Biomed Res Int. 2014;2014:691505
references: 24724093
references: Arch Gen Psychiatry. 2008 Jun;65(6):694-701
references: 18519827
references: J Psychiatr Res. 2011 Aug;45(8):1055-66
references: 21296361
references: Alcohol Clin Exp Res. 2002 Apr;26(4):558-64
references: 11981133
references: Proc Natl Acad Sci U S A. 2013 Mar 12;110(11):4251-4
references: 23319626
references: Am Psychol. 2001 Jan;56(1):16-26
references: 11242984
references: J Neurol Neurosurg Psychiatry. 1985 Mar;48(3):211-7
references: 3981189
references: Alcohol Clin Exp Res. 2008 Mar;32(3):386-94
references: 18302722
references: Neuroimage. 1999 Feb;9(2):179-94
references: 9931268
references: Biol Psychiatry. 2005 May 15;57(10):1117-27
references: 15866551
references: Chem Biodivers. 2007 Aug;4(8):1614-48
references: 17712811
references: Behav Brain Res. 2011 Oct 10;224(1):128-34
references: 21664935
references: Neuroimage. 2000 Jun;11(6 Pt 1):805-21
references: 10860804
references: J Stud Alcohol. 1989 Jan;50(1):30-7
references: 2927120