Sleep-wake schedules

Lavie, P. (1986). Ultrashort sleep-waking schedule. III. Gates and forbidden zones for sleep. Electroencephalogr. Clin. Neurophysiol 63, 414-25. 

The final category is termed the sleep-wake schedule disorders. These are seen in people who get their days and nights turned around. The most common examples are shift workers and travelers with jet lag. Additionally, in the elderly, especially those with dementia, a malfunction in the circadian biological rhythm that regulates sleep can leave them awake and alert at night but drowsy and sleeping during the day. 

Transient disturbances may occur as a result of rapid time zone changes (as in transoceanic flights) or staying up late for a few days. Diagnosis of a sleep— wake schedule disorder, however, is made only if complaints meet criteria for an insomnia or a hypersomnia disorder. These disorders often improve when the person is able to resume a normal sleep—wake pattern. 

Lavie P, Scherson A. Ultrashort sleep-waking schedule. I. Evidence of ultradian rhyth-micity in sleepability. Electroencephalogr Clin Neurophysiol 1981 52 163-174. 

Lavie P, Zomer J. Ultrashort sleep-waking schedule. II. Relationship between ultradian rhythms in sleepability and the REM-NONREM cycles and effects of the circadian phase. Electroencephalogr and Clin Neurophysiol 1984 57 35 -2. 

Moreover, there is evidence for increased rates of ADHD symptoms in clinical populations of children with sleep disorders, including children with the obstructive sleep apnea syndrome (OSAS), periodic limb movements of sleep (PLMS), narcolepsy, and sleep-wake schedule disorders. Studies indicate that treating the primary sleep disorder can produce significant improvement in ADHD symptoms (103). 

Manber R, Bootzin RR, Acebo C, Carskadon MA. The effects of regularizing sleep-wake schedules on daytime sleepiness. Sleep 1996 19(5) 432—441. 

IV. Sleep-Wake Schedules, Driving Management, and Traffic Accidents... 

Until the mid 90s, no study demonstrated the main factors responsible for sleep-related accidents. We questioned, apart from organic sleep disorders, whether modifications of the sleep-wake schedules could be responsible for sleepiness at the wheel. Studying large populations of drivers (22,23), we demonstrated that long-distance driving was frequently associated with sleep curtailment. Our first study (22), performed on a freeway rest stop area in 1993, showed that 50% of drivers (n = 567 drivers) reduced their sleep duration in the 24 hr before departure for a long-distance journey. Ten percent of drivers had no sleep in the 24 hr before the interview. These stunning results could have been explained by a... 

Naitoh et al. (45) employed a sleep/wake schedule of 20-min naps every 6 hr during a 64-hr period of continuous work, comparing this experimental condition against a second condition comprising total sleep deprivation for the entire 64-hr period. Compared to the sleep deprivation condition, the 20-min naps significantly reduced the cumulative effects of sleep loss on a four-choice reaction time task. 

Actigraphs In support of the sleep/duty diaries, objective sleep/wake schedules were assessed using activity monitors (Mini Mitter, Sunriver, Oregon), which were worn by each pilot. Activity monitors are devices worn like a wristwatch on the wrist that allow for 24-hour recordings of activity (see Ancoli-Israeil, 2002). The activity monitor is a light-weight deviee that eontains a piezo-electric accelerometer which measures the... 

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