Eef L. Theunissen & Gerold F. Kauert & Stefan W. Toennes & Manfred R. Moeller & Anke Sambeth & Mathieu M. Blanchard & Johannes G. Ramaekers
Cannabis is the most frequently used illicit drug in theWestern world, with estimates going up to 18% of Europeans having tried cannabis at least once in their life (Rigter and van Laar 2002). The widespread use of cannabis and its potential for increased therapeutic use have given rise to significant public
health concern, mostly regarding the effects of cannabis on cognition and psychomotor function. The acute effects of !9-tetrahydrocannabinol (THC), the
major psychotropic compound in cannabis, on cognitive and psychomotor performance have been assessed in numerous experimental studies using within-subject, double-blind, placebo-controlled designs. These have generallyshown that THC in doses between 40 and 300 “g/kgcauses a dose-dependent reduction in performance at testsmeasuring memory, attention, reaction time (RT), tracking,and motor function (Curran et al. 2002; Halland Solowij1998; Heishman et al. 1997).