“Enjoy the honey-heavy dew of slumber.”
Shakespeare,   Julius Caesar.

Russell Foster is a circadian neuroscientist:  He studies the sleep cycles of the brain.  And he asks: What do we know about sleep?

According to Foster, some areas of the brain are actually more active during the sleep state than during the wake state.  There are dozens of different ideas about why we sleep. Here are three of them.

The first is sort of the restoration idea, and it’s somewhat intuitive. Essentially, all the stuff we’ve burned up during the day, we restore, we replace, we rebuild during the night.

The second idea addresses the concept of energy conservation. You essentially sleep to save calories.

The third idea concerns brain processing and memory consolidation. Our ability to come up with novel solutions to complex problems is hugely enhanced by a night of sleep.  Sleeping at night enhances our creativity.

In the 1950s, good data suggests that most of us were getting around eight hours of sleep a night. Nowadays, we sleep one and a half to two hours less every night, so we’re in the six-and-a-half-hours every-night league. For teenagers, it’s worse. They need nine hours for full brain performance, and many of them, on a school night, are only getting five hours of sleep.  It’s simply not enough.

Another aspect of loss of sleep is weight gain. If you sleep around about five hours or less every night, then you have a 50 percent likelihood of being obese.  What’s the connection here?  Well, sleep loss seems to give rise to the release of the hormone ghrelin, the hunger hormone.

How do you get more sleep?  Foster recommends the following:  Make your bedroom a haven for sleep. The first critical thing is make it as dark as you possibly can, and also make it slightly cool.  Turn off mobile phones.  Turn off computers.  Turn off all of those things that are also going to excite the brain.  Try not to drink caffeine too late in the day, ideally not after lunch.1

by Patrick Gaffney

by Patrick Gaffney


1 The content of this blog was taken from:  Foster, Russell.  “Why Do We Sleep?”  Retrieved from:  www.Ted.com.