Neurobehavioural Associations of Recurrent Short Sleep in School-Aged Children

Recurrent cycles of weekday short sleep and weekend sleep extension have been shown to result in more prominent neurobehavioural impairments during subsequent weeks of sleep restriction in adolescents and young adults. Whether the same would be observed in school-aged children is unclear. In this micro-longitudinal observational cohort study, 79 children (6-12 years old, 34 males) were tracked for 16 days at home. Sleep was measured using actigraphy. Neurobehavioural functions-processing speed, working memory, vigilance, subjective sleepiness and affect-were assessed daily through a smartphone application. Forty participants had a daily average time-in-bed of less than 9 h on weekdays but at least 9 h on weekends (short sleep group), while 39 participants had at least 9 h on both weekdays and weekends (well-rested group). There were no significant group × day interactions for any neurobehavioural measure (p > 0.61), but the short sleep group reported overall higher levels of subjective sleepiness (mean Karolinska Sleepiness Scale score [SE]: 4.51 [0.21] vs. 3.77 [0.21], p = 0.01) and lower positive affect (score on the 10-item Positive and Negative Affect Schedule for Children: 12.84 [0.64] vs. 15.15 [0.65], p = 0.01) than the well-rested group. Within the short sleep group, none of the neurobehavioural measures showed observable weekday-weekend differences or compounding impairments during the second cycle of weekday short sleep. Unlike in adolescents and young adults, recurrent cycles of short sleep on weekdays and sleep extension on weekends may not be associated with compounding neurobehavioural impairments in school-aged children.