Sleep need

Franken, P., Chollet, D. Tafti, M. (2001). The homeostatic regulation of sleep need is under genetic control. J. Neurosci 21 (8), 2610-21. 

T. (2003a). The role of nitric oxide in regulation of sleep need. J. Neurophysiol. 26, (suppl), A32-3. 

The importance of adenosine deaminase in the duration and intensity of sleep in humans has been noted recently (Retey et al. 2005). Animal studies suggest that sleep needs are genetically controlled, and this also seems to apply in humans. Probably, a genetic variant of adenosine deaminase, which is associated with the reduced metabolism of adenosine to inosine, specifically enhances deep sleep and slow wave activity during sleep. Thus low activity of the catabolic enzyme for adenosine results in elevated adenosine, and deep sleep. In contrast, insomnia patients could have a distinct polymorphism of more active adenosine deaminase resulting in less adenosine accumulation, insomnia, and a low threshold for anxiety. This could also explain interindividual differences in anxiety symptoms after caffeine intake in healthy volunteers. This could affect the EEG during sleep and wakefulness in a non-state-specific manner. 

SLEEP NEEDS CHANGE THROUGHOUT THE LIFE SPAN... 

IV. The Concepts and Definitions of Sleep Need, Sleep Debt, and Extra Sleep. 559... 

The previous studies led to the hypothesis that the insomnia patients may be suffering from a state of chronic activation that disturbs night sleep but protects against or prevents EDS from occurring in the morning. Conversely, such patients may be naturally short sleepers whose sleep need may be fulfilled with relatively short sleep at night. 

The average newborn sleeps about 16 out of every 24 hr in bouts of 1 4 hr (7). Sleep decreases to about 13 hr at 1 year and consists of nocturnal sleep plus two daytime naps. By 4-5 years old, most children have given up naps and spend at least 10 hr asleep at night (8). We believe that older children and adolescents need at least 9 hr of sleep, although most obtain far less than that amount. These familiar generalizations about changes in sleep duration across age are based on studies in both naturalistic settings and the laboratory. Rarely, however, is the construct of sleep need addressed directly and we must be careful not to confuse usual sleep duration with sleep need. 

Strauch I, Meier B. Sleep need in adolescents a longitudinal approach. Sleep 1988 ll(4) 378-386. 

National Research Council/Institute of Medicine. Sleep needs, patterns, and difficulties of adolescents summary of a workshop. Washington, DC National Academy Press, 2000. 

Hartmann E, Baekeland F, Zwilling G, Hoy P. Sleep need how much sleep and what kind Am J Psychiatry 1971 127(8) 1001-1008. 

Mathematical analyses of EEG SWA have yielded quantitative information about the time course of accumulation and discharge of sleep need. The dynamics of the sleep/wake-dependent changes in delta power have been quantified with the use of computer simulations, and delta power can now be predicted in detail. The increase of sleep need during waking can be described by an exponentially saturating curve with a time constant (Tj) of 18.2 hr in humans (37) and 8.6 hr in... 

If we assume that the steady state value in the last week of the 10-hr-pho-toperiod (14 hr in bed) schedule represented the real daily sleep need for this group of subjects, we may conclude that all amounts of sleep above these values represented extra or makeup sleep. Accordingly, the mean payback of sleep debt for the group averaged about 30 hr. For purposes of comparison, individuals who were not at all sleep-deprived would have to spend more than 3 consecutive days with no sleep at all to accumulate a sleep debt of similar magnitude. 

The conscious ones capable of abandoning sleep need not die... they can live forever. 

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