Sharp and sleepy: evidence for dissociation between sleep pressure and nocturnal performance.

While sleep restriction decreases performance, not all individuals are equal with regard to sensitivity to sleep loss. We tested the hypothesis that performance could be independent of sleep pressure as defined by EEG alpha-theta power. Twenty healthy subjects (10 vulnerable and 10 resistant) underwent sleep deprivation for 25 h.

The effects of coffee and napping on nighttime highway driving: a randomized trial.

Background: Sleep-related accidents often involve healthy young persons who are driving at night. Coffee and napping restore alertness, but no study has compared their effects on real nighttime driving performances.

Objective: To test the effects of 125 mL of coffee (half a cup) containing 200 mg of caffeine, placebo (decaffeinated coffee containing 15 mg of caffeine), or a 30-minute nap (at 1:00 a.

Fatigue, sleepiness, and performance in simulated versus real driving conditions.

Study Objectives: To determine whether real-life driving would produce different effects from those obtained in a driving simulator on fatigue, performances and sleepiness.

Design: Cross-over study involving real driving (1200 km) or simulated driving after controlled habitual sleep (8 hours) or restricted sleep (2 hours).

Setting: Sleep laboratory and open French Highway.

Effects of sleep deprivation on Color-Word, Emotional, and Specific Stroop interference and on self-reported anxiety.

The aim of this study was principally to assess the impact of sleep deprivation on interference performance in short Stroop tasks (Color-Word, Emotional, and Specific) and on subjective anxiety. Subjective sleepiness and performance on a psychomotor sustained attention task were also investigated to validate our protocol of sleep deprivation. Twelve healthy young subjects were tested at four-hourly intervals through a 36-h period of wakefulness under a constant routine protocol.

Sleep duration and caffeine consumption in a French middle-aged working population.

Objective/background: To explore the association between sleep duration and daily caffeine intake in a working population. Caffeine acutely disrupts sleep in the laboratory, but the inter-relations between sleep and caffeine intake in daily life are ill-known.

Methods: Questionnaire and diary based survey of 1498 persons from the GAZEL cohort of employees of the National Electricity and Gas Company (EDF-GDF) working in various locations in the Paris and South-West France areas.