Sleep deprivation

===Attention and working memory===
Among the possible physical consequences of sleep deprivation, deficits in attention and [[working memory]] are perhaps the most important;<ref name="Alhola" /> such lapses in mundane routines can lead to unfortunate results, from forgetting ingredients while cooking to missing a sentence while taking notes. Performing tasks that require attention appears to be correlated with the number of hours of sleep received each night, declining as a function of hours of sleep deprivation.<ref>{{Cite book|title = An Introduction to Brain and Behavior| vauthors = Kolb B, Whishaw I |publisher = Worth Publishers|year = 2014|isbn = 978-1-4292-4228-8|location = New York, New York|pages = 468–469|edition = 4th}}</ref> Working memory is tested by methods such as choice-reaction time tasks.<ref name="Alhola" />

Attentional lapses also extend into more critical domains in which the consequences can be life or death; car crashes and industrial disasters can result from inattentiveness attributable to sleep deprivation. To empirically measure the magnitude of attention deficits, researchers typically employ the [[psychomotor vigilance task]] (PVT), which requires the subject to press a button in response to a light at random intervals. Failure to press the button in response to the stimulus (light) is recorded as an error, attributable to the microsleeps that occur as a product of sleep deprivation.<ref>{{cite journal | vauthors = Innes CR, Poudel GR, Jones RD | title = Efficient and regular patterns of nighttime sleep are related to increased vulnerability to microsleeps following a single night of sleep restriction | journal = Chronobiology International | volume = 30 | issue = 9 | pages = 1187–1196 | date = November 2013 | pmid = 23998288 | doi = 10.3109/07420528.2013.810222 | s2cid = 4682794 }}</ref>

Crucially, individuals' subjective evaluations of their fatigue often do not predict actual performance on the PVT. While totally sleep-deprived individuals are usually aware of the degree of their impairment, lapses from chronic (lesser) sleep deprivation can build up over time so that they are equal in number and severity to the lapses occurring from total (acute) sleep deprivation. Chronically sleep-deprived people, however, continue to rate themselves considerably less impaired than totally sleep-deprived participants.<ref name="SleepDepPVT">{{cite journal | vauthors = Van Dongen HP, Maislin G, Mullington JM, Dinges DF | title = The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation | journal = Sleep | volume = 26 | issue = 2 | pages = 117–126 | date = March 2003 | pmid = 12683469 | doi = 10.1093/sleep/26.2.117 | url = http://www.aasmnet.org/Resources/FactSheets/DrowsyDriving.pdf | url-status = live | doi-access = free | archive-url = https://web.archive.org/web/20110718152642/http://www.aasmnet.org/Resources/FactSheets/DrowsyDriving.pdf | archive-date = 18 July 2011 }}</ref> Since people usually evaluate their capability on tasks like driving subjectively, their evaluations may lead them to the false conclusion that they can perform tasks that require constant attention when their abilities are in fact impaired.{{cn|date=April 2023}}