by John Medina

SLEEP

Meet Dr. John Medina. He wrote the book Brain Rules.

There are 12 Brain Rules.

Exercise Survival Wiring Attention

Short-termmemory

Long-termmemory

Sleep Stress

ExplorationGenderVisionSensoryIntegration

We're going tolook at sleep.

Rule #7Sleep well,think well.

Why does sleep matter? We sleep for 1/3 of our lives, so it must be important. Yet scientists are only starting to understand it.

Sleep makes us vulnerable to predators, so it must be important and necessary.

We'll look at sleep in these ways:

1. What's going on in the sleeping brain?2. How does sleep work?3. Larks, owls, and hummingbirds4. The nap zone5. Sleep = good6. No sleep = bad7. Sleep-friendly world

What's going on in the sleeping brain?

1

The brain isn't inactive when you're sleeping.

The brain isn't inactive when you're sleeping. It's busy with legions of neurons crackling electrical commands.

A laboratory study showed that while a rat was sleeping, its brain was learning about the maze it was running earlier.

How does sleep work?

2

Sleep involves a battle between two opposing drives. It's called the circadian rhythm.

The circadian arousal system keeps you awake. This is called “Process C.”

The homeostatic sleep drive makes you sleep. This is called “Process S.”

The longer one army controls, the more likely it is to lose. That's why you can't stay awake or asleep forever. And that's why we're constantly bouncing between sleep and wakefulness.

3 Larks, owls, & hummingbirds

Sleep patterns vary from person to person.

Meet the morning larks. They wake up early and go to bed early.

About 10% ofus are larks.

Night owls wake up late and go to bed early.

About 20% of usare night owls.

The other 70% of us us are hummingbirds. Some are more larkish, some more owlish, some in between.

Which kind of bird are you?

4 The nap zone

Sleep rhythms fight their battle around the clock not just at night.__

Most of us want to sleep a little during the day. There's a reason for that. Some cultures have even made it an institution. In Spain it's called “siesta”.

Scientists now know there's a “nap zone” that happens when the Process C and Process S curves converge. Perfect time for a nap!

Nap Zone

Here's how to calculate yournap zone: Add 12 hours after the mid-point of your sleep. So if you go to bed at 11 p.m. and wake up at 7 a.m., your nap zone would start at 3 p.m. This is an oversimplification but a general rule of thumb.

A NASA study showed a 26- minute nap improved a pilot's performance by more than 35%.

If that's what a nap can do, imagine the benefits of a full night's sleep!

Sleep = good5

Have you ever gone to sleep with something on your mind, and woken to find that you have the answer?

Mountains of data show that a healthy sleep can boost learning significantly,for certaintypes of tasks.

Sleep has been shown to enhance tasks that involve visual texture discrimination, motor adaptations, and motor sequencing.

But learning a procedure appears most sensitive to sleep improvement.

You know the phrase “Let's sleep on it”?

It helps!

No sleep = bad6

Sleep loss cripples thinking in just about every way you can measure thinking: Attention Executive function Immediate memory Working memory mood Quantitative skills Logical reasoning Math knowledge

Eventually, sleep loss affects manual dexterity, including fine motor control and even gross motor movements, such as the ability to walk.

Sleep-friendly world

7

The effects of sleep deprivation are thought to cost businesses in the US more than $100 billion a year.

What if businesses and schools took the sleep needs of their employees and students seriously? Here are some ideas...

Variable Schedules What if we matched chronotypes to work schedules? Remember larks and owls? We might gain more productivity and quality of life

Promote Napping What if businesses and schools were serious about the nap zone? We wouldn't schedule meetings or exams during the nap zone. We could create a space for people to take a half-hour nap every day.

Sleeping On It Organizations might tackle their hardest problems by sending the team on a mini-retreat. They'd be presented with the problem and asked to think about it. But they wouldn't start talking or sharing until they had slept about eight hours.

Learn moreabout thebrain at theBrain Ruleswebsite:brainrules.net

Thanks to Garr Reynolds for inspiringthis slideshow. Check out his "BrainRules for Presenters" presentationon SlideShare.