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Circadian and sleep/wake dependent aspects of subjective alertness and cognitive performance.

Dijk, DJ, Duffy, JF and Czeisler, CA (1992) Circadian and sleep/wake dependent aspects of subjective alertness and cognitive performance. J Sleep Res, 1 (2). pp. 112-117.

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Circadian and sleep/wake dependent processes underlying variations in subjective alertness and cognitive performance were assessed in a constant routine protocol and in a protocol in which the sleep/wake cycle was uncoupled from the output of the endogenous circadian pacemaker. In the latter protocol, the contribution of a sleep/wake dependent process and a circadian process to alertness and performance were separated by folding the data at either the period of the sleep/wake cycle or at the period of the endogenous circadian body temperature rhythm. This analysis revealed that prior wakefulness within a range of 0-18 h significantly reduced alertness and performance and that the circadian rhythm of core body temperature paralleled the circadian rhythm of alertness and performance. During the first 16 h of the constant routine protocol, which coincided with the subjects' habitual period of wakefulness, alertness and performance remained at a stable level. The latter finding was explained by assuming that during our usual waking day the circadian system counteracts the detrimental effects of increasing duration of prior wakefulness.

Item Type: Article
Divisions : Surrey research (other units)
Authors :
Duffy, JF
Czeisler, CA
Date : June 1992
Uncontrolled Keywords : Adolescent, Adult, Body Temperature, Circadian Rhythm, Cognition, Humans, Male, Sleep, Time Factors, Wakefulness
Related URLs :
Depositing User : Symplectic Elements
Date Deposited : 17 May 2017 09:10
Last Modified : 24 Jan 2020 16:13

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