Cannabis and alcohol: Effects on estimation of time and distance

Marihuana vs. Alcohol: A Pharmacologic Comparison

“…Contrastingly, marihuana showed a much greater effect than alcohol on the abilities to estimate time and distance (38) which are essential in the judgment of speed. This effect was unique for marihuana in that the drivers realized that the time elapsed or distance traveled only "seemed" greater; a difference between subjective and objective judgment.…”

“…The early effect includes an activation of social, sensual and verbal behavior which is followed by sedation and reduced contact with the environment. However, one of the most striking differences is the action of marihuana in producing an apparent lengthening of time (35,36,37,38). This effect has been shown most clearly in human studies where subjects consistently overestimate time periods whereas alcohol produces an inconsistent opposite effect.…”

“…However, this study has been criticized for the probable use of weak marihuana, use of only one dose level and lack of ability to disguise the drug leading to possible bias by young pro-marihuana subjects (51). A more recent study of driving skills in a more sophisticated Danish study used oral consumption of three different marihuana doses (52,38,53). Eating marihuana is another widespread form of usage and makes the rate of action more comparable to alcohol.…”

Cannabis, Atropine, and Temporal Information Processing

“…Experiment 2 replicated the THC effect on STR when subjects were counting subjective seconds. This result indicates that THC affects the experience of time as it is passing, and not solely the memory for duration experience after a time period.An early report on cannabinoid intoxication (Cl) de scribed alterations in temporal experiences [Moreau de Tours, 1845], Most current marijuana users concur, claiming that objective time seems lengthened during Cl; in a questionnaire distributed by Tart [1970] to experi enced users, 95% indicated that 'time passes very slowly' during Cl.Laboratory investigations have repeatedly demon strated Cl-induced changes in time judgments [Bech et al, 1973;Cappel et al, 1972;Carlini et al, 1974; Do mino et al …”

Le cannabis est-il un produit dopant ?

“…Cet état de relaxation, pouvant aller jusqu'à une forte somnolence, est accompagné d'une légère euphorie et d'une distorsion des perceptions visuelles et auditives. Ces modifications comportementales, qui par ailleurs font du cannabis un des facteurs majeurs de l'insécurité routière (18,(21)(22)(23)(24)(25), peuvent constituer dans certaines disciplines sportives un handicap certain (Figure 1). …”