M Rizzo1, C T J Lamers, C G Sauer, J G Ramaekers, A Bechara, G J Andersen. 1. Division of Neuroergonomics and Division of Behavioral Neurology and Cognitive Neuroscience, Department of Neurology, The University of Iowa Carver College of Medicine, Iowa City, IA, USA. matthew-rizzo@uiowa.edu
Abstract
RATIONALE: Illicit drug use can increase driver crash risk due to loss of control over vehicle trajectory. This study asks, does recreational use of +/-3,4-Methylenedioxymethamphetamine (MDMA; ecstasy) and tetrahydrocannabinol (THC; marijuana) impair cognitive processes that help direct our safe movement through the world? OBJECTIVE: This study assesses the residual effects of combined MDMA/THC use, and of THC use alone, upon perceived trajectory of travel. METHODS: Perception of self-motion, or heading, from optical flow patterns was assessed using stimuli comprising random dot ground planes presented at three different densities and eight heading angles (1, 2, 4 and 8 degrees to the left or right). On each trial, subjects reported if direction of travel was to the left or the right. RESULTS: Results showed impairments in both drug groups, with the MDMA/THC group performing the worst. CONCLUSIONS: The finding that these psychoactive agents adversely affect heading perception, even in recently abstinent users, raises potential concerns about MDMA use and driving ability.
RATIONALE: Illicit drug use can increase driver crash risk due to loss of control over vehicle trajectory. This study asks, does recreational use of +/-3,4-Methylenedioxymethamphetamine (MDMA; ecstasy) and tetrahydrocannabinol (THC; marijuana) impair cognitive processes that help direct our safe movement through the world? OBJECTIVE: This study assesses the residual effects of combined MDMA/THC use, and of THC use alone, upon perceived trajectory of travel. METHODS: Perception of self-motion, or heading, from optical flow patterns was assessed using stimuli comprising random dot ground planes presented at three different densities and eight heading angles (1, 2, 4 and 8 degrees to the left or right). On each trial, subjects reported if direction of travel was to the left or the right. RESULTS: Results showed impairments in both drug groups, with the MDMA/THC group performing the worst. CONCLUSIONS: The finding that these psychoactive agents adversely affect heading perception, even in recently abstinent users, raises potential concerns about MDMA use and driving ability.
Authors: R J Verkes; H J Gijsman; M S Pieters; R C Schoemaker; S de Visser; M Kuijpers; E J Pennings; D de Bruin; G Van de Wijngaart; J M Van Gerven; A F Cohen Journal: Psychopharmacology (Berl) Date: 2001-01-01 Impact factor: 4.530
Authors: P Marquet; P A Delpla; S Kerguelen; J Bremond; F Facy; M Garnier; B Guery; M Lhermitte; D Mathé; A L Pelissier; C Renaudeau; P Vest; J P Seguela Journal: J Forensic Sci Date: 1998-07 Impact factor: 1.832