Sleep fragmentation

The possibility that adenosine production was reduced or deficiently accumulated during wakefulness, which would explain the reduction in SWS, sleep fragmentation, and overall reduced sleep drive in the older animals, was also... 

All these drugs reduce sleep duration, decrease SWS and REM sleep, increase sleep latency and increase sleep fragmentation. They can cause a dose-related insomnia during use, and hypersomnia with increased dreaming and nightmares on withdrawal after chronic use. 

AD subjects have a higher prevalence of sleep disturbances than normal elderly, including sleep fragmentation, advancement of the sleep-wake cycle, and decreased amounts of slow wave and rapid-eye movement (REM) sleep (Prinz et al., 1982 Reynolds et al., 1988 Bliwise et al., 1989). Sleep-wake cycle disruption in AD has been associated with a greater burden of neuropsychiatric disturbances (Rebok et al., 1991 Ancoli-Israel et al., 1994), particularly apathy and delusions (Kaufer et al., 2001). Several studies have observed a relationship between the degree of intellectual impairment and REM sleep abnormalities (Prinz et al., 1982 Vitiello et al., 1984 Moe et al., 1995), underscoring the role of REM sleep in memory consolidation (Wilson McNaughton, 1994). 

A wide range of sleep disturbances has been documented in PD (Larsen, 2001). In a population-based survey of sleep disorders in PD, Tandberg et ah (1998) reported nocturnal sleeping problems in 60% of PD patients compared to 33% in healthy controls and 46% in elderly with diabetes mellitus. The most common problem reported was sleep fragmentation, which was found in 39% of PD and only 12% of normal elderly controls, whereas inability to fall asleep did not differ between the groups. 

Roehrs T, Merlotti L, Petracelli N, Stepanski E, Roth T. Experimental sleep fragmentation. Sleep 1994 17(5 ) 43 8 -43. 

Finally, it is important to clarify the complex relationship between maternal sleep (sleep deprivation, sleep fragmentation, and sleepiness), maternal mood,... 

Martin S, Wrath PK, Deary U, Douglas NJ. The effect of nonvisible sleep fragmentation on daytime function. Am J Respir Crit Care Med 1997 155 1596-1601. 

Stepanski EJ. The effect of sleep fragmentation on daytime function. Sleep 2002 25 268-276. 

Stepanski E, Lamphere J, Badia P, Zorick F, Roth T. Sleep fragmentation and daytime sleepiness. Sleep 1984 7( 1) 18—26. 

Carskadon MA, Brown ED, Dement WC. Sleep fragmentation in the elderly relationship to daytime sleep tendency. Neurobiol Aging 1982 3 321-327. 

Doghramji K, Browman CP, Gaddy JR, Walsh JK. Triazolam diminishes daytime sleepiness and sleep fragmentation in patients with periodic leg movements in sleep. J Clin Psychopharmacol 1991 11 284-290. 

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