Taking a nap makes you brainier

Posted by Emma Woollacott

Leave this article up on your screen - in case the boss comes by - and settle down comfortably. According to University of California scientists, a lunchtime nap not only refreshes you but can actually make you smarter.

The team had already established that pulling an all-nighter left students worse at learning. But now they're being encouraged to sleep during the day as well as at night.

"Sleep not only rights the wrong of prolonged wakefulness but, at a neurocognitive level, it moves you beyond where you were before you took a nap," said lead investigator Matthew Walker.

Walker and his team gave 39 students a tricky learning task at noon, and then packed half of them off for forty winks. Later that day, they were all given a new set of tests.

While the students who had stayed awake did rather worse at these, the nappers were better at learning.

The UC Berkeley researchers' reckon that the reason for this is that sleep is needed to clear the brain's short-term memory storage and make room for new information.

They've even pin-pointed exactly when this happens, they say: during stage 2 non-REM sleep, which takes place between deep sleep (non-REM) and the dream state known as Rapid Eye Movement (REM). This may explain why humans spend at least half their sleeping hours in Stage 2 non-REM, Walker said.