Comparing Sleep‐Loss Sleepiness and Sleep Inertia: Lapses Make the Difference

Abstract

To compare the behavioral effects of sleep-loss sleepiness (performance impairment due to sleep loss) and sleep inertia (period of impaired performance that follows awakening), mean response latencies and number of lapses from a visual simple reaction-time task were analyzed. Three experimental conditions were designed to manipulate sleepiness and sleep-inertia levels: uninterrupted sleep, partial sleep reduction, and total sleep deprivation. Each condition included two consecutive nights (the first always a night of uninterrupted sleep, and the second either a night of uninterrupted sleep, a night when sleep was reduced to 3 h, or a night of total sleep deprivation), as well as two days in which performance was assessed at 10 different time points (08:00, 08:30, 09:00, 09:30, 10:00, 11:00, 14:00, 17:00, 20:00, and 23:00 h). From 08:00 to 09:00 h, reaction times in the partial sleep-reduction and total sleep-deprivation conditions were at a similar level and were slower than those observed in the uninterrupted sleep condition. In the same time period, the frequency of lapses in the total sleep-deprivation condition was higher than in the partial sleep-reduction condition, while this latter condition never differed from the uninterrupted sleep condition. The results indicate that both sleep inertia and sleep-loss sleepiness lead to an increase in response latencies, but only extreme sleepiness leads to an increase in lapse frequency. We conclude that while reaction times slow as a result of both sleep inertia and sleep-loss sleepiness, lapses appear to be a specific feature of sleep-loss sleepiness.

Contribution of Core Body Temperature, Prior Wake Time, and Sleep Stages to Cognitive Throughput Performance During Forced Desynchrony

“…Only the amount of REM sleep had a significant, albeit relatively weak, main effect wherein reductions in REM sleep were associated with poorer waking performance. Reductions in NREM S1 and S2 sleep and REM sleep occur in response to chronic sleep restriction, which concomitantly elicit deficits in waking performance (e.g., Belenky et al, 2003;Miccoli L et al, 2008;Van Dongen et al, 2003). Our results demonstrate an analogous relationship between REM sleep and cognitive performance in the absence of underlying chronic sleep restriction.…”

Interindividual Differences in Neurobehavioral Performance in Response to Increasing Homeostatic Sleep Pressure

“…The performance decline on both tasks with increasing hours awake in our study confirmed the detrimental impact of increasing homeostatic sleep pressure on neurobehavioral function shown in most sleep-deprivation studies (e.g., Doran et al, 2001;Horne & Pettitt, 1985;Lorenzo et al, 1995;Miccoli et al, 2008). Unlike previous studies, though, circadian variation was controlled for across wakefulness in the current study.…”

The Effect of 40 Hours of Constant Wakefulness on Number Comparison Performance

“…This has been shown in studies examining the effects of total sleep loss and circadian rhythms on human performance (e.g., Carrier & Monk, 2000;Johnson et al, 1992;Miccoli et al, 2008). Several studies have shown that cognitive performance suffers especially consequences.…”