Sleep deprivation chronic partial

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

The PVT has been a primary performance assay for demonstrating the cumulative neurocognitive effects from chronic partial sleep deprivation... 

Van Dongen HPA, Dinges DF. Chronic partial sleep deprivation data point to a novel process regulating waking behavioural alertness. Sleep 2002 //(suppl 1) 232. 

Van Dongen HPA, Shah AD, de Brunier AB, Dinges DF. Behavioural alertness and the two-process model of sleep regulation during chronic partial sleep deprivation. Sleep 2002, 77(suppl 1) 233. 

Very little work has addressed the topic of individual differences in response to sleep deprivation. It is clear that such differences exist total sleep deprivation produces remission of symptoms in depressed patients but does not have such large impact on mood in normals patients with chronic insomnia should suffer from significant partial sleep deprivation but actually seem less sleepy than normals when tested with the MSLT (48,49). It is certainly possible that individual differences in response to sleep deprivation are related to individual differences in sleep requirement. However, these individual differences may also be related to other intrinsic factors (such as level of central nervous system arousal, biological rhythms, or personality) or extrinsic factors (such as characteristic activity or light exposure patterns). 

The duration of the problem determines whether transient or chronic insomnia underlies sleep loss. Transient insomnia refers to no more than a few nights of poor sleep, which generally results from challenges such as (a) acute illness, (b) stress, (c) suboptimal circadian time for sleep, or (d) a disruptive sleep environment. In the absence of these challenges the individuals typically sleep normally. That is, they judge their sleep to be satisfactory. It is reasonable to conclude, therefore, that the impact of transient insomnia on waking function can be extrapolated from partial sleep deprivation research conducted in normal sleepers. Such studies limit the amount of sleep obtained, on one or more nights, just as in the case of transient insomnia. 

Although large-scale controlled studies on chronic partial sleep deprivation and sleep extension are difficult to execute, we have been able to acquire a great deal of knowledge from the well-conducted investigations that have been carried out to date. Chronic partial sleep deprivation unquestionably leads to accumulation of impairment and progressively increased sleep tendency, the sum of which have been referred to as sleep debt. Once sleep debt has accrued, it can only be paid back by extra sleep. 

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