title: Effects of slow-release caffeine and a nap on driving simulator performance after partial sleep deprivation.
abstract: A driving simulator was used to evaluate the effectiveness of a 30-min. nap and 300-mg slow-release caffeine as countermeasures to drivers' sleepiness induced by partial sleep deprivation. 12 participants were allowed 45 hr. time in bed at the laboratory. Driving performance then was measured twice--at 9 a.m. and at 1 p.m.--by a 45-min. driving task on a simulator. Subjective sleepiness/alertness and mood were assessed four times on the Stanford Sleepiness Scale and the Profile of Mood States. Driving performance was assessed as Lane Drifting, Speed Deviation, and Accident Liability. A 30-min. nap opportunity and 300 mg of slow-release caffeine both were successful in counteracting drivers' sleepiness. The remedial effect of slow-release caffeine lasted longer than that of the nap, that is, it was also effective in the afternoon session. This suggests that slow-release caffeine represents a valuable countermeasure that, in the case of partial sleep deprivation, is preferred to a nap when sleepiness has to be counteracted for a longer time.
authors.affiliation: Department of Psychology, Free University of Brussels, Belgium. Elke.De.Valck@vub.ac.be
authors.forename: Elke
authors.initials: E
authors.lastname: De Valck
authors.forename: Esther
authors.initials: E
authors.lastname: De Groot
authors.forename: Raymond
authors.initials: R
authors.lastname: Cluydts
mesh_terms: D000063:Accidents, Traffic / Q000517:prevention & control / Q000523:psychology; D000328:Adult; D000339:Affect / Q000187:drug effects; D001143:Arousal / Q000187:drug effects*; D001288:Attention / Q000187:drug effects*; D002940:Circadian Rhythm / Q000187:drug effects; D003131:Combined Modality Therapy; D003198:Computer Simulation; D003692:Delayed-Action Preparations; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D012890:Sleep; D012892:Sleep Deprivation / Q000188:drug therapy* / Q000523:psychology; D016896:Treatment Outcome; D014851:Wakefulness / Q000187:drug effects
chemical_list: D003692:Delayed-Action Preparations