Grey Matter Volume Differences Associated with Extremely Low Levels of Cannabis Use in Adolescence

TY - JOUR

T1 - Grey Matter Volume Differences Associated with Extremely Low Levels of Cannabis Use in Adolescence

AU - Orr, Catherine

AU - Spechler, Philip

AU - Cao, Zhipeng

AU - Albaugh, Matthew

AU - Chaarani, Bader

AU - Mackey, Scott

AU - D'Souza, Deepak

AU - Allgaier, Nicholas

AU - Banaschewski, Tobias

AU - Bokde, Arun L W

AU - Bromberg, Uli

AU - Büchel, Christian

AU - Burke Quinlan, Erin

AU - Conrod, Patricia

AU - Desrivières, Sylvane

AU - Flor, Herta

AU - Frouin, Vincent

AU - Gowland, Penny

AU - Heinz, Andreas

AU - Ittermann, Bernd

AU - Martinot, Jean-Luc

AU - Martinot, Marie-Laure Paillère

AU - Nees, Frauke

AU - Papadopoulos Orfanos, Dimitri

AU - Paus, Tomáš

AU - Poustka, Luise

AU - Millenet, Sabina

AU - Fröhner, Juliane H

AU - Radhakrishnan, Rajiv

AU - Smolka, Michael N

AU - Walter, Henrik

AU - Whelan, Robert

AU - Schumann, Gunter

AU - Potter, Alexandra

AU - Garavan, Hugh

N1 - Copyright © 2019 the authors 0270-6474/19/391818-11$15.00/0.

PY - 2019/3/6

Y1 - 2019/3/6

N2 - Rates of cannabis use among adolescents are high, and are increasing concurrent with changes in the legal status of marijuana and societal attitudes regarding its use. Recreational cannabis use is understudied, especially in the adolescent period when neural maturation may make users particularly vulnerable to the effects of Δ-9-tetrahydrocannabinol (THC) on brain structure. In the current study, we used voxel-based morphometry to compare gray matter volume (GMV) in forty-six 14-year-old human adolescents (males and females) with just one or two instances of cannabis use and carefully matched THC-naive controls. We identified extensive regions in the bilateral medial temporal lobes as well as the bilateral posterior cingulate, lingual gyri, and cerebellum that showed greater GMV in the cannabis users. Analysis of longitudinal data confirmed that GMV differences were unlikely to precede cannabis use. GMV in the temporal regions was associated with contemporaneous performance on the Perceptual Reasoning Index and with future generalized anxiety symptoms in the cannabis users. The distribution of GMV effects mapped onto biomarkers of the endogenous cannabinoid system providing insight into possible mechanisms for these effects.SIGNIFICANCE STATEMENT Almost 35% of American 10th graders have reported using cannabis and existing research suggests that initiation of cannabis use in adolescence is associated with long-term neurocognitive effects. We understand very little about the earliest effects of cannabis use, however, because most research is conducted in adults with a heavy pattern of lifetime use. This study presents evidence suggesting structural brain and cognitive effects of just one or two instances of cannabis use in adolescence. Converging evidence suggests a role for the endocannabinoid system in these effects. This research is particularly timely as the legal status of cannabis is changing in many jurisdictions and the perceived risk by youth associated with smoking cannabis has declined in recent years.

AB - Rates of cannabis use among adolescents are high, and are increasing concurrent with changes in the legal status of marijuana and societal attitudes regarding its use. Recreational cannabis use is understudied, especially in the adolescent period when neural maturation may make users particularly vulnerable to the effects of Δ-9-tetrahydrocannabinol (THC) on brain structure. In the current study, we used voxel-based morphometry to compare gray matter volume (GMV) in forty-six 14-year-old human adolescents (males and females) with just one or two instances of cannabis use and carefully matched THC-naive controls. We identified extensive regions in the bilateral medial temporal lobes as well as the bilateral posterior cingulate, lingual gyri, and cerebellum that showed greater GMV in the cannabis users. Analysis of longitudinal data confirmed that GMV differences were unlikely to precede cannabis use. GMV in the temporal regions was associated with contemporaneous performance on the Perceptual Reasoning Index and with future generalized anxiety symptoms in the cannabis users. The distribution of GMV effects mapped onto biomarkers of the endogenous cannabinoid system providing insight into possible mechanisms for these effects.SIGNIFICANCE STATEMENT Almost 35% of American 10th graders have reported using cannabis and existing research suggests that initiation of cannabis use in adolescence is associated with long-term neurocognitive effects. We understand very little about the earliest effects of cannabis use, however, because most research is conducted in adults with a heavy pattern of lifetime use. This study presents evidence suggesting structural brain and cognitive effects of just one or two instances of cannabis use in adolescence. Converging evidence suggests a role for the endocannabinoid system in these effects. This research is particularly timely as the legal status of cannabis is changing in many jurisdictions and the perceived risk by youth associated with smoking cannabis has declined in recent years.

U2 - 10.1523/JNEUROSCI.3375-17.2018

DO - 10.1523/JNEUROSCI.3375-17.2018

M3 - SCORING: Journal article

C2 - 30643026

VL - 39

SP - 1817

EP - 1827

JO - J NEUROSCI

JF - J NEUROSCI

SN - 0270-6474

IS - 10

ER -