Habitual sleep

Park YM, Matsumoto K, Shinkoda H, Nagashima H, Kang MJ, Seo Yf. Age and gender difference in habitual sleep-wake rhythm. Psychiatry Clin Neurosci 2001 55 201-202. 

A creative series of studies found that young adult volunteers could reduce their habitual sleep from 8 hr to about 5 hr with almost undetectable effects on performance or mood, except for an increase in sleepiness (42,43). Such investigations should be repeated and expanded, to see if such sleep restriction is so free of morbid risk. 

In summary, habitual sleep durations of 5-7 hr confer little mortality risk, and perhaps no substantial morbidity, although those with short sleep durations may fall asleep more rapidly and sleep more soundly. 

Qureshi AI, Giles WH, Croft JB, Bliwise DL. Habitual sleep patterns and risk for stroke and coronary heart disease a 10-year follow-up from NHANES I. Neurology 1997 48 904-911. 

Benoit O, Foret J, Bouard G, Merle B, Landau J, Marc ME. Habitual sleep length and patterns of recovery sleep after 24 hour and 36 hour sleep deprivation. Electroencephalogr Clin Neurophysiol 1980 50 477-485. 

Only one study has carefully looked at characteristic performance or alertness as a function of habitual sleep duration. Taub (34,35) examined performance in groups of 7.5-hr- and 10-hr-sleeping university students. The long sleepers were found to have significantly shorter reaction time, improved vigilance per-... 

Hicks RA, Pellegrini RJ, Martin S, Garbesi L, Elliott D, Hawkins J. Type A behavior and normal habitual sleep duration. Bull Psychonom Soc 1979 14 185-186. 

Hicks RA, Rozette E. Habitual sleep duration and eating disorders in college students. Percept Mot Skills 1986 62 209-210. 

Hicks RA, Pellegrini RJ, Hawkins J, Moore JD. Self-reported consistency of normal habitual sleep durations of college students. Percept Mot Skills 1978 47 457-458. 

The diagnostic criteria for insomnia can indeed become very precise. Insomnia in the ICSD [3] was defined as the complaint of an insufficient amount of sleep or not feeling rested after the habitual sleep episode , which might denote that sleep quantity and quality should be considered as equivalent. However, there were actually two quantitative requirements in ICSD for the diagnosis of insomnia at least 20 min sleep latency and at the most 6.5 hours total sleep time, otherwise the condition was considered as sleep state misperception also called pseudoinsomnia [3],... 

Zhdanova, I. V., Wurtman, R. J., Morabito, C., Piotrovska, V. R. Lynch, H. J. (1996). Effects of low oral doses of melatonin, given 2-4 hours before habitual bedtime, on sleep in normal young humans. Sleep 19, 423-31. 

A striking phenomenon which probably involves biochemical individuality is that of pathological intoxication. Occasionally an individual, who may be a habitual drinker or not, is afflicted. In a typical case the individual goes berserk and may commit all sorts of crimes and cause damage to property. After a subsequent long sleep he has no memory of his acts.9 This very special type of drunkenness is not caused by any special type of alcohol or necessarily by large amounts it fortunately happens only rarely, and involves only a few individuals. Whether certain individuals are peculiarly susceptible and have repeated typical attacks (these would be classed, no doubt, as alcoholic psychotics) is not clear in any event only certain rare individuals ever are in such a condition as to be susceptible. 

Bohlin G. Monotonous stimulation, sleep onset and habituation of the orienting reaction. Electroencephalogr Clin Neurophysiol. 1971 31 593-601. 

Aeschbach D, Cajochen C, Landolt H, Borbely AA. Homeostatic sleep regulation in habitual short sleepers and long sleepers. Am J Physiol 1996 270 R41-R53. 

Benoit O, Foret J, Bouard G. The time course of slow wave sleep and REM sleep in habitual long and short sleepers effect of prior wakefulness. Hum Neurobiol 1983 2 91-96. 

Masa JF, Rubio M, Findley LJ. Habitually sleepy drivers have a high frequency of automobile crashes associated with respiratory disorders during sleep. Am J Respir Crit Care Med 2000 162(4 Pt 1) 1407-1412. 

Meney I, Waterhouse J, Atkinson G, Reilly T, Davenne D. The effect of one night s sleep deprivation on the temperature, mood, and physical performance in subjects with different amounts of habitual physical acivity. Chronobiol Int 1998 15 349-363. 

In summary, caffeine is a known psychostimulant that exerts positive effects on physical endurance, alertness, and vigilance. The effects on reaction time and EEG activity are debatable. Caffeine may cause small, but inconsequential, increases in blood pressure, particularly in people who do not habitually use this compound. Although the effects on mood are generally positive, increased anxiety may result from doses of 300 mg or more. Caffeine s most reliable effects appear to occur in sleep-deprived personnel in whom doses ranging from 250 to 600 mg (including sustained-release caffeine doses of 300-600 mg) have been shown to improve wakefulness, mood, and various aspects of performance. 

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