Sleep restriction

Buscemi, N., Vandermeer, B., Hooton, N. et al. (2006). Efficacy and safety of exogenous melatonin for secondary sleep disorders and sleep disorders accompanying sleep restriction meta-analysis. Br. Med. J. 332, 385-93. 

Rogers, P. J., Heatherley, S. V., Hayward, R. C. et al. (2005). Effects of caffeine and caffeine withdrawal on mood and cognitive performance degraded by sleep restriction. Psychopharmacology 179 (4), 742-52. 

Behavioral and educational interventions that may help include shortterm cognitive behavioral therapy, relaxation therapy, stimulus control therapy, cognitive therapy, sleep restriction, paradoxical intention, and sleep hygiene education (Table 72-3). 

Acute Phase Treatment. Hypnotic medications are useful for short-term treatment of insomnia, but they should always be accompanied by behavioral and psychoeducational treatments, including a review of good sleep hygiene practices. It may also include more aggressive measures such as relaxation training, sleep restriction therapy, and stimulus control therapy. 

Sleep restriction attempts to decrease the amount of time spent in bed versus the actual amount of time spent sleeping. The goal is to achieve a window of sleep efficiency between 80% and 90%. Thus, if above or below this range, one would increase or decrease time in bed by 15 to 20 minutes. 

Chronic partial sleep restriction is a topic of current interest and one that was examined two decades ago by Carskadon and Dement (18). During a week of restriction to 5 hr of sleep a night, 10 college-aged adults manifested an accumulating decrease of sleep latency scores that did not plateau. A more recent chronic sleep restriction study (34) showed a. 95 correlation of performance measures with the Carskadon and Dement MSLT scores. These studies provided important support for the concept of sleep deficits that continue to grow as sleep reduction is prolonged. A more recent interpretation implicates excess wake as the primary factor rather than sleep deficit (35). 

Carskadon MA, Dement WC. Cumulative effects of sleep restriction on daytime sleepiness. Psychophysiology 1981 18 107-113. 

Dinges DF, Pack F, Williams K, Gillen KA, Powell JW, Ott GE, Aptowicz C, Pack AI. Cumulative sleepiness, mood disturbance, and psychomotor vigilance performance decrements during a week of sleep restricted to 4—5 hours per night. Sleep 1997 20(4) 267-277. 

Van Dongen HP, Maislin G, Mullington JM, Dinges DF. The cumulative cost of additional wakefulness dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation. Sleep 2003 26(2) 117-126. 

Chronic sleep restriction (cumulative partial sleep deprivation)... 

Figure 4 PVT performance responses to varying doses of daily sleep. Mean PVT lapses per day (07 30-23 30), measured at 2-hr intervals, expressed relative to baseline (BL), in subjects randomized to an 8-hr (n = 9 open diamond), 6-hr (n = 13 open square), or 4-hr (n = 13 open circle) sleep opportunity per day for 14 consecutive days or 0-hr (n = 13 closed square) sleep condition across 3 days. The curves represent statistical nonlinear model-based best-fitting profiles of the PVT performance response to sleep loss. The mean ( s.e.m.) ranges of neurobehavioral functions for 1 and 2 days of total sleep deprivation (0 hr sleep) are illustrated by the light and dark bands, respectively, allowing comparison of the 3-day total sleep deprivation condition and the 14-day chronic sleep restriction conditions. (From Ref. 35.)...

For example, in the two largest laboratory-controlled dose-response experiments conducted to date on the neurobehavioral effects of chronic sleep restriction, cumulative increases were evident in the average number of PVT lapses per 24 hr across days of sleep restricted to 3, 4, 5, and 6 hr per night... 

Moreover, daily PVT lapse rates increased at a more rapid rate in the reduced sleep conditions. Figure 4 displays the results from the first of these studies, in which subjects were restricted to 4, 6, or 8-hr time in bed for sleep for 14 consecutive days (35). The results were compared to 88 hr of total sleep deprivation. Figure 4 illustrates the dose-response relationship between sleep opportunity and the degree of impairment in PVT performance. Interestingly, this cumulative impairment was found to be almost linear for lapse rates. Further, subjects randomized to the 4- and 6-hr sleep restriction conditions reached levels of impairment equivalent to those of subjects undergoing 1-2 nights of total sleep deprivation. 

In an earlier experiment, cumulative increases in PVT lapses across 7 days of sleep restricted to approximately 5 hr per night (29) were shown to be strongly related (r = -0.95) to sleep onset latency as assessed by the Multiple Sleep Latency Test (MSLT) in a nearly identical protocol (72). It appears that PVT performance lapse frequency and the well-validated physiological measure of sleep propensity may reflect the same basic process of escalating sleep pressure with sleep loss. 

Belenky G, Wesensten NJ, Thorne DR, Thomas ML, Sing HC, Redmond DP, Russo MB, Balkin TJ. Patterns of performance degradation and restoration during sleep restriction and subsequent recovery a sleep-dose response study. J Sleep Res 2003 12 1-12. 

The effect of sleep loss associated with medical disorders can manifest in several ways. Several studies have reported on the detrimental effects of sleep restriction on neurobehavioral functioning. Following only one night of restricted sleep decreased neurobehavioral performance and increased subjective sleepiness and sleep propensity have been reported (1). When the number of nights of sleep restriction is extended beyond one, cumulative decrements in neurobehavioral functioning (2,3) and increased daytime sleepiness levels are evident (4). 

Meerlo P, Koehl M, van der Borght K, Turek FW, Investigator Turek FW. Sleep restriction alters the hypothalamic-pituitary-adrenal response to stress. J... 

We are using the term inadequate sleep instead of sleep deprivation in our title for a number of reasons. First, few studies have aimed specifically to deprive children or adolescents of sleep. We describe some research on experimental sleep restriction in children but most of these studies fall far short of common deprivation paradigms in animals or even adult humans. Instead, most research in younger humans has assessed outcome measures such as school grades, self-reported sleepiness, and so forth as a function of variations in self-selected or usual sleep patterns with the expectation that children and adolescents who obtain lower than normal amounts of sleep will manifest deficits. Thus, inadequate sleep is defined by sleep characteristics of a sample. We also wanted to note some of the literature on sleep that is disturbed or disrupted due to disease processes such as apnea or periodic leg movements the duration of sleep in sleep disorders may or may not be shortened or restricted although it is likely fragmented and otherwise abnormal. We decided on the term inadequate sleep with the hope that it would encompass these different areas of concern. 

VI. Experimental Studies of Sleep Restriction/Disruption and Circadian Timing... 

The results from the studies described above indicate that the MSLT provides a robust measure of sleepiness that is sensitive to sleep restriction in children and adolescents (112). Patterns of sleep latency from repeated naps during constant routine protocols or forced desynchrony protocols in older children and adolescents also illustrate the influences of both homeostatic and circadian processes on sleepiness/alertness and provide evidence for the hypothesis that... 

Results from other variables assessed in sleep restriction studies are less consistent. For example, some studies have found no deficits in tasks assessing motor skills (48,49), auditory attention (47,48), sustained attention and response inhibition (50), memory tasks (47,49,139), and computational accuracy... 

Clearly, more experimental research is needed to tease apart the developmental influences of sleep restriction and/or disruption on a range of daytime functioning behaviors and cognitive skills. Additionally, studies are needed that restrict sleep for extended periods of time to identify deficits that may be associated with the typical sleep patterns of children and adolescents. 

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