title: Response inhibition and elevated parietal-cerebellar correlations in chronic adolescent cannabis users.
abstract: The ability to successfully inhibit an inappropriate behaviour is a crucial component of executive functioning and its impairment has been linked to substance dependence. Cannabis is the most widely used illicit drug in adolescence and, given the accelerated neuromaturation during adolescence, it is important to determine the effects of cannabis use on neurocognitive functioning during this developmental period. In this study, a cohort of adolescent heavy cannabis users and age-matched non-cannabis-using controls completed a Go/No-Go paradigm. Users were impaired in performance on the task but voxelwise and region-of-interest comparisons revealed no activation differences between groups. Instead, an analysis of correlation patterns between task-activated areas revealed heightened correlation scores in the users between bilateral inferior parietal lobules and the left cerebellum. The increased correlation activity between these regions was replicated with resting state fMRI data and was positively correlated with self-reported, recent cannabis usage. The results suggests that the poorer inhibitory control of adolescent cannabis users might be related to aberrant connectivity between nodes of the response inhibition circuit and that this effect is observable in both task-induced and intrinsic correlation patterns. This article is part of the Special Issue Section entitled 'Neuroimaging in Neuropharmacology'.
authors.affiliation: School of Psychology, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.
authors.forename: B
authors.initials: B
authors.lastname: Behan
authors.affiliation: Department of Psychiatry, University of California, San Francisco, CA, USA.
authors.forename: C G
authors.initials: CG
authors.lastname: Connolly
authors.affiliation: School of Psychology, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.
authors.forename: S
authors.initials: S
authors.lastname: Datwani
authors.affiliation: School of Psychology, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.
authors.forename: M
authors.initials: M
authors.lastname: Doucet
authors.affiliation: School of Psychology, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.
authors.forename: J
authors.initials: J
authors.lastname: Ivanovic
authors.affiliation: Department of Psychiatry, University of Vermont, Burlington, VT, USA; Department of Psychology, University of Vermont, Burlington, VT, USA.
authors.forename: R
authors.initials: R
authors.lastname: Morioka
authors.affiliation: School of Psychology, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.
authors.forename: A
authors.initials: A
authors.lastname: Stone
authors.affiliation: Department of Radiology, University of Vermont, Burlington, VT, USA.
authors.forename: R
authors.initials: R
authors.lastname: Watts
authors.affiliation: Health Service Executive, Dublin, Ireland; Department of Public Health & Primary Care, Trinity College Dublin, Dublin 2, Ireland.
authors.forename: B
authors.initials: B
authors.lastname: Smyth
authors.affiliation: School of Psychology, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland; Department of Psychiatry, University of Vermont, Burlington, VT, USA; Department of Psychology, University of Vermont, Burlington, VT, USA. Electronic address: hugh.garavan@uvm.edu.
authors.forename: H
authors.initials: H
authors.lastname: Garavan
mesh_terms: D000293:Adolescent; D001921:Brain / Q000187:drug effects / Q000503:physiopathology*; D001931:Brain Mapping; D002531:Cerebellum / Q000187:drug effects / Q000503:physiopathology; D056344:Executive Function / Q000187:drug effects / Q000502:physiology; D005260:Female; D006801:Humans; D007266:Inhibition, Psychological; D008279:Magnetic Resonance Imaging; D008297:Male; D002189:Marijuana Abuse / Q000503:physiopathology* / Q000523:psychology*; D009434:Neural Pathways / Q000187:drug effects / Q000503:physiopathology; D009483:Neuropsychological Tests; D010296:Parietal Lobe / Q000187:drug effects / Q000503:physiopathology; D011597:Psychomotor Performance / Q000187:drug effects / Q000502:physiology*; D012146:Rest; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Cannabis; Neuroimaging; Response inhibition