The inability to fully recover from several nights of sleep restriction to 5h/night even after 2 nights of extended sleep raises the question of how successive cycles of sleep restriction impact teens who undergo sleep restriction week after week. During a school term, adolescents often expose themselves to repeated cycles of short sleep on school nights followed by catch-up sleep over the weekend in an effort to maintain alertness and wellbeing. Some students catch up on sleep by napping in the afternoon.
In NFS2, adolescents underwent a sleep schedule that simulated weekday sleep loss and the attempt to “catch up” sleep over the weekend. We tracked changes in cognitive performance, subjective sleepiness, and mood during two successive cycles of sleep restriction and recovery to determine whether behavioral deficits would be made worse by a second exposure to sleep restriction. We also examined the effectiveness of afternoon naps in reducing deficits associated with sleep restriction.
We found that negative effects of weekday sleep restriction on neurobehavioral function cumulated and were incompletely reversed by weekend catch-up sleep. A second cycle of sleep restriction made performance worse than that observed at the end of the first week of sleep restriction, indicating failure to fully recover from sleep loss over the weekend. Afternoon naps attenuated but did not eliminate performance decline. Napping and weekend catch-up sleep countermeasures were still inferior to adequate and regular nocturnal sleep.