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Ocular measures of sleepiness are increased in night shift workers undergoing a simulated night shift near the peak time of the 6-sulfatoxymelatonin rhythm

Ftouni, S., Sletten, T.L., Nicholas, C.L., Kennaway, D.J., Lockley, S.W. and Rajaratnam, S.M.W. (2015) Ocular measures of sleepiness are increased in night shift workers undergoing a simulated night shift near the peak time of the 6-sulfatoxymelatonin rhythm Journal of Clinical Sleep Medicine, 11 (10). 1131-1141A.

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Study Objectives: The study examined the relationship between the circadian rhythm of 6-sulphatoxymelatonin (aMT6s) and ocular measures of sleepiness and neurobehavioral performance in shift workers undergoing a simulated night shift. Methods: Twenty-two shift workers (mean age 33.4, SD 11.8 years) were tested at approximately the beginning (20:00) and the end (05:55) of a simulated night shift in the laboratory. At the time point corresponding to the end of the simulated shift, 14 participants were classifi ed as being within range of 6-sulphatoxymelatonin (aMT6s) acrophase\- defi ned as 3 hours before or after aMT6s peak\-and 8 were classifi ed as outside aMT6s acrophase range. Participants completed the Karolinska Sleepiness Scale (KSS) and the auditory psychomotor vigilance task (aPVT). Waking electroencephalography (EEG) was recorded and infrared refl ectance oculography was used to collect ocular measures of sleepiness: positive and negative amplitude/velocity ratio (PosAVR, NegAVR), mean blink total duration (BTD), the percentage of eye closure (%TEC), and a composite score of sleepiness levels (Johns Drowsiness Scale; JDS). Results: Participants who were tested within aMT6s acrophase range displayed higher levels of sleepiness on ocular measures (%TEC, BTD, PosAVR, JDS), objective sleepiness (EEG delta power frequency band), subjective ratings of sleepiness, and neurobehavioral performance, compared to those who were outside aMT6s acrophase range. Conclusions: The study demonstrated that objective ocular measures of sleepiness are sensitive to circadian rhythm misalignment in shift workers.

Item Type: Article
Authors :
Ftouni, S.
Sletten, T.L.
Nicholas, C.L.
Kennaway, D.J.
Rajaratnam, S.M.W.
Date : 2015
DOI : 10.5664/jcsm.5086
Uncontrolled Keywords : Circadian misalignment, Oculometrics, Performance, Shift work, Sleepiness, 6 hydroxymelatonin o sulfate, 6-sulfatoxymelatonin, melatonin, adult, alertness, Article, circadian rhythm, clinical article, cognition, delta rhythm, electroencephalography, eyelid closure, eyelid movement, eyelid reflex, female, human, infrared oculography, Johns Drowsiness Scale, Karolinska Sleepiness Scale, male, night work, shift worker, sleep disorder assessment, somnolence, velocity, adolescent, analogs and derivatives, blinking, circadian rhythm, circadian rhythm sleep disorder, middle aged, pathophysiology, physiology, psychomotor performance, sleep stage, urine, work schedule, young adult, Adolescent, Adult, Blinking, Circadian Rhythm, Electroencephalography, Female, Humans, Male, Melatonin, Middle Aged, Psychomotor Performance, Sleep Disorders, Circadian Rhythm, Sleep Stages, Work Schedule Tolerance, Young Adult
Depositing User : Clive Harris
Date Deposited : 17 Jun 2020 01:17
Last Modified : 17 Jun 2020 01:17

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