Neurobehavioural functions during variable and stable short sleep schedules. (16th December 2020)

• Record Type: Journal Article
• Authors: Koa, Tiffany B.; Lo, June C.
• Is Part Of: Journal of sleep research. Volume 30:Number 4(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-12-16
• Subjects: cognitive performance -- mood -- night‐to‐night sleep variability -- sleep restriction -- sleepiness; Sleep -- Periodicals; Sleep disorders -- Periodicals; 612.821
• DOI: 10.1111/jsr.13252
• Languages: English
• ISSNs: 0962-1105

Abstract

Abstract: We investigated whether variable sleep schedules might mitigate the neurobehavioural deficits induced by multiple nights of sleep restriction. In this 4‐night experiment, 78 young adults (age: 18–28 years) were randomly assigned to four groups: 8888, 8666, 8846 and 8486, where each digit corresponded to time‐in‐bed in hours for each study night. After one baseline night of 8‐hr time‐in‐bed, time‐in‐bed remained unchanged for the 8888 group, while the other groups had short sleep schedules (total time‐in‐bed = 18 hr) that differed in the number of time‐in‐bed changes. Sleep was monitored using actigraphy at home. Daytime neurobehavioural functions were assessed in the laboratory at single time points, after the baseline night, and again after 3 nights of the sleep manipulation period. For sustained attention, the 8888 group responded faster in the Psychomotor Vigilance Task after the manipulation period ( p = .01), while responses became slower for the less variable sleep schedules (8666 and 8846; p < .01), but not the most variable sleep schedule (8486; p = .14). Processing speed also improved in the 8888 group and the variable 8846 and 8486 groups ( p < .01), but not in the stable 8666 group ( p = .09). Furthermore, subjective sleepiness was preserved in the 8888 and, importantly, 8486 groups ( p > .05), but was elevated in the 8666 and 8846 groups ( p < .05). These findings suggest that when sleep opportunities are limited across multiple nights, a variable sleep schedule that allows for prophylactic and/or recovery sleep on some nights may mitigate some daytime neurobehavioural deficits as compared with a schedule with no opportunity for recovery.