title: Dose-dependent effects of cannabis on the neural correlates of error monitoring in frequent cannabis users.
abstract: Cannabis has been suggested to impair the capacity to recognize discrepancies between expected and executed actions. However, there is a lack of conclusive evidence regarding the acute impact of cannabis on the neural correlates of error monitoring. In order to contribute to the available knowledge, we used a randomized, double-blind, between-groups design to investigate the impact of administration of a low (5.5 mg THC) or high (22 mg THC) dose of vaporized cannabis vs. placebo on the amplitudes of the error-related negativity (ERN) and error positivity (Pe) in the context of the Flanker task, in a group of frequent cannabis users (required to use cannabis minimally 4 times a week, for at least 2 years). Subjects in the high dose group (n=18) demonstrated a significantly diminished ERN in comparison to the placebo condition (n=19), whereas a reduced Pe amplitude was observed in both the high and low dose (n=18) conditions, as compared to placebo. The results suggest that a high dose of cannabis may affect the neural correlates of both the conscious (late), as well as the initial automatic processes involved in error monitoring, while a low dose of cannabis might impact only the conscious (late) processing of errors.
authors: Cognitive Psychology Unit, Institute of Psychology, Leiden University, Leiden, Netherlands; Leiden Institute for Brain and Cognition, Leiden, Netherlands. Electronic address: m.a.kowal@fsw.leidenuniv.nl.
authors: Mikael A
authors: MA
authors: Kowal
authors: Cognitive Psychology Unit, Institute of Psychology, Leiden University, Leiden, Netherlands; Leiden Institute for Brain and Cognition, Leiden, Netherlands.
authors: Henk
authors: H
authors: van Steenbergen
authors: Cognitive Psychology Unit, Institute of Psychology, Leiden University, Leiden, Netherlands; Leiden Institute for Brain and Cognition, Leiden, Netherlands.
authors: Lorenza S
authors: LS
authors: Colzato
authors: Bedrocan BV, Veendam, Netherlands.
authors: Arno
authors: A
authors: Hazekamp
authors: Leiden Institute for Brain and Cognition, Leiden, Netherlands; Department of Psychiatry, Leiden University Medical Center, Leiden, Netherlands.
authors: Nic J A
authors: NJ
authors: van der Wee
authors: Cognitive Psychology Unit, Institute of Psychology, Leiden University, Leiden, Netherlands.
authors: Meriem
authors: M
authors: Manai
authors: Cognitive Psychology Unit, Institute of Psychology, Leiden University, Leiden, Netherlands.
authors: Jeffrey
authors: J
authors: Durieux
authors: Cognitive Psychology Unit, Institute of Psychology, Leiden University, Leiden, Netherlands; Leiden Institute for Brain and Cognition, Leiden, Netherlands.
authors: Bernhard
authors: B
authors: Hommel
mesh_terms: D001921:Brain / Q000187:drug effects* / Q000503:physiopathology*; D002188:Cannabis; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D013759:Dronabinol / Q000008:administration & dosage*; D004569:Electroencephalography; D005260:Female; D006213:Hallucinogens / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D002189:Marijuana Abuse / Q000503:physiopathology* / Q000523:psychology; D008606:Mental Processes / Q000187:drug effects* / Q000502:physiology; D009330:Nebulizers and Vaporizers; D009483:Neuropsychological Tests; D011930:Reaction Time / Q000187:drug effects; D055815:Young Adult
chemical_list: D006213:Hallucinogens; D013759:Dronabinol
keywords: Cannabis; Error monitoring; Error positivity; Error-related negativity; THC