Name: Amazing Effects of Sleep (And Lack of It)
Uploaded: 2014-05-04T13:05:45.000Z
Duration: 3 min 59 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

"On the fifth day he saw in the crystal a transatlantic whale with a square face"

That's from a research paper about a 24-year-old guy known as Z. He approached a couple of

researchers in the 1930s to ask if they could help him stop sleeping.

"He was convinced that sleep is a habit and that with proper procedures this habit could

be broken. On several occasions he had gone without sleep for four or five days"

It's one of a whole bunch of really weird sleep experiments from 50 to 80 years ago.

In this one, the guy, Z, thought that if he could be stimulated by tasks and other people

to stay awake for more than a week, he'd get a second wind and never need to sleep again.

So the researchers gave him a typewriter and asked him to type for 30 minutes a day, marking

each minute of typing. They would compare his typing speed and accuracy as one measure

to find out the effects of sleeplessness.

Throughout the 10 days of not sleeping his pulse, blood pressure and the chemicals in

his pee all stayed the same. He did a bunch of intelligence tests every day and his marks

But... his typing speed declined and after day 4, Z couldn't type anymore. He couldn't

fixate on letters and numbers and he said his eyes were sore.

Still, Z stayed up and didn't complain about mental or physical fatigue.

He did become easily irritated. He started reporting hallucinations and he mistook his

On the last day of the experiment he wrote a nice poem (link in the description) and

The researchers concluded it was possible to go with practically no sleep for ten days

without any known physiological effects or damage to mental function. Similar studies

found no known damage from sleeplessness.

Now, after 50 odd years more research, we know sleep deprivation leads to depression,

high blood pressure, increased risk of diabetes, weight gain, heart disease and probably earlier

death. We also know that a good nights' sleep is kind of a big deal. Research from the past

few years suggests we need seven to nine hours a night to for our memory to function. If

When we sleep we go through cycles that last for 70-to-120 minutes. In these cycles there

are two main types of sleep: REM or rapid-eye-movement and non-REM. Your brain needs both of these

types of sleep to consolidate memories. During non-REM or deep sleep, your brain files away

the facts and practices the moves learned that day--it consolidates them for more permanent

storage. During REM sleep, your brain integrates these facts and lessons into your existing

In one study, two groups had to learn a set of new words, some real (like "cathedral")

and some made up (like "cathedruke"). The sleep group memorised the words in the evening,

had a recall test, slept for the night, and took another test. The no-sleep group got

their words in the morning, had a recall test, stayed awake for the day, and then took the

The subjects in the sleep group showed improved recall after sleeping the night; the no-sleep

group showed no measurable improvements and were worse on some aspects of recall. One

week later, the no-sleep group showed improved recall once they had a chance to get some

shut eye. Sleep is crucial to forming short and long term memories.

And fully knitting information into your memory requires seven to nine hours of sleep. 50

years ago, 3% of working Americans reported getting less than six hours a night --now

it's 30%. Cutting off the last two hours of the night means you're missing out on your

The next time you feel like your life is over capacity, don't pull an all-nighter or a ten

day no-sleep binge. Science says it's best to sleep on it.

How quickly can you subscribe to BrainCraft? If you've just pulled an all-nighter the quarter

of a second it would take you to hit the subscribe button nearly triples to 800 or 900 milliseconds.

If you want to rest your reaction time, click pause right... Now.