title: Heart rate variability during sedentary work and sleep in normal and sleep-deprived states.
abstract: The possibility of using heart rate variability (HRV) as an indicator of sleepiness was investigated by analysing heart rate (HR) activity and electroencephalography (EEG) recordings from 10 individuals who performed a monotonous attention task for 120 min in both sleep-deprived and rested states. In both conditions, measurements were collected during 60 min of sleep immediately following a 120 min of non-sleep (awake phase). Although HR decreased significantly in both the rested and the sleep-deprived states during the awake phase, HR significantly changed sooner when subjects were sleep-deprived than when they were rested. No significant changes in HRV were found during the awake phase; however, HRV correlated significantly with alpha and theta power densities when rested but not when sleep-deprived. During the sleep phase, the total HRV and very low and low frequency HRV components significantly decreased approximately 40 min after sleeping in the sleep-deprived condition. These HRV components were also significantly and negatively correlated with delta power densities. HRV does not seem to be a viable indicator of sleepiness; however, HRV may be useful for determining sleep stages.
authors.affiliation: National Institute of Working Life, Umeå, Sweden. johannes.berg@niwl.se
authors.forename: Johannes
authors.initials: J
authors.lastname: van den Berg
authors.forename: Gregory
authors.initials: G
authors.lastname: Neely
authors.forename: Urban
authors.initials: U
authors.lastname: Wiklund
authors.forename: Ulf
authors.initials: U
authors.lastname: Landström
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D004569:Electroencephalography / Q000379:methods; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D012016:Reference Values; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000503:physiopathology*; D011795:Surveys and Questionnaires; D013647:Task Performance and Analysis; D013997:Time Factors; D014851:Wakefulness / Q000502:physiology; D014937:Work / Q000502:physiology*