Medicosnext
A new study has found that short naps are not effective in mitigating the negative cognitive effects of sleep deprivation. Michigan State University’s Sleep and Learning Lab, where the study was conducted, concluded that a nap during the day will not restore a sleepless night. However, while short naps didn’t show measurable effects on relieving sleep deprivation effects, the amount of slow-wave sleep (SWS, the deepest and most restorative stage of sleep) obtained during the nap was associated with reduced impairments due to sleep deprivation.
The study had 275 sleep-deprived college-aged participants who, after undergoing cognitive tasks in the evening to measure attention and the ability to complete a series of steps in a set order without skipping or repeating them (even after being interrupted), were randomly given the opportunity to either have a full night’s sleep or to remain awake overnight, with the latter given the choice of no nap or a 30-min or 60-min nap. The first group was sent home to sleep; the second stayed at the lab overnight and took either a 30- or a 60-minute nap; and the third were not allowed to nap at all.
The participants were again asked to undertake the cognitive tasks in the morning. The sleep-deprived participants made significantly more errors than those sent home to sleep. However, in those who had taken naps, slow-wave sleep (SWS, the deepest and most restorative stage of sleep) was associated with reduced errors, with every 10-minute increase in SWS reducing errors after interruptions by about four percent.
The takeaway? Naps, even if they include SWS, cannot replace a full night of sleep.
