Tuesday, December 5

Sleep Facts Part 1

Due to my recent prolonged lack of sufficient sleep, I decided to look up some sleep facts. I found these interesting. I'll post the second part tomorrow.

-The record for the longest period without sleep is 18 days, 21 hours, 40 minutes during a rocking chair marathon. The record holder reported hallucinations, paranoia, blurred vision, slurred speech and memory and concentration lapses.

- It's impossible to tell if someone is really awake without close medical supervision. People can take cat naps with their eyes open without even being aware of it.

- Anything less than five minutes to fall asleep at night means you're sleep deprived. The ideal is between 10 and 15 minutes, meaning you're still tired enough to sleep deeply, but not so exhausted you feel sleepy by day.

- A new baby typically results in 400-750 hours lost sleep for parents in the first year

- One of the best predictors of insomnia later in life is the development of bad habits from having sleep disturbed by young children.

- The continuous brain recordings that led to the discovery of REM (rapid eye-movement) sleep were not done until 1953, partly because the scientists involved were concerned about wasting paper.

- REM sleep occurs in bursts totalling about 2 hours a night, usually beginning about 90 minutes after falling asleep.

- Dreams, once thought to occur only during REM sleep, also occur (but to a lesser extent) in non-REM sleep phases. It's possible there may not be a single moment of our sleep when we are actually dreamless.

- REM dreams are characterised by bizarre plots, but non-REM dreams are repetitive and thought-like, with little imagery - obsessively returning to a suspicion you left your mobile phone somewhere, for example.

- Certain types of eye movements during REM sleep correspond to specific movements in dreams, suggesting at least part of the dreaming process is analagous to watching a film

- No-one knows for sure if other species dream but some do have sleep cycles similar to humans.

- Elephants sleep standing up during non-REM sleep, but lie down for REM sleep.

- Some scientists believe we dream to fix experiences in long-term memory, that is, we dream about things worth remembering. Others reckon we dream about things worth forgetting - to eliminate overlapping memories that would otherwise clog up our brains.

- Dreams may not serve any purpose at all but be merely a meaningless byproduct of two evolutionary adaptations - sleep and consciousness.

- REM sleep may help developing brains mature. Premature babies have 75 per cent REM sleep, 10 per cent more than full-term bubs. Similarly, a newborn kitten, puppy, rat, or hampster experiences only REM sleep, while a newborn guinea pig (which is much more developed at birth) has almost no REM sleep at all.


- Scientists have not been able to explain a 1998 study showing a bright light shone on the backs of human knees can reset the brain's sleep-wake clock.

- British Ministry of Defence researchers have been able to reset soldiers' body clocks so they can go without sleep for up to 36 hrs. Tiny optical fibres embedded in special spectacles project a ring of bright white light (with a spectrum identical to a sunrise) around the edge of soldiers' retinas, fooling them into thinking they have just woken up. The system was first used on US pilots during the bombing of Kosovo.

- Seventeen hours of sustained wakefulness leads to a decrease in performance equivalent to a blood alcohol-level of 0.05%.

- The 1989 Exxon Valdez oil spill off Alaska, the Challenger space shuttle disaster and the Chernobyl nuclear accident have all been attributed to human errors in which sleep-deprivation played a role.

6 comments:

Anonymous said...

Other studies show that people sleeping in Church tend to have neck problems later in life.

megs said...

i've heard that if someone is sleep deprived for 24 hours or more, you are considered legally drunk. YIKES!!

daniel said...

Your comment regarding the '1998 study showing a bright light shone on the backs of human knees can reset the brain's sleep-wake clock' intrigued me, so I looked into it more. It turns out that really was a study back in 1998 that was published in Science. Science is a great journal for publishing exciting (though usually incorrect) data. This turns out to be the case for the light on the back of the knee study. In 2002 Wright and Czeisler from Harvard replicated the study with 22 patients and found that there was no reseting of the sleep-wake clock upon administration of knee light.

So anyways, just thought that might interest you (it did me).

daniel said...

Oh, and, yes...I'm a nerd. But I guess that might be redundant. ;)

Anonymous said...

I want part 2!

Luke said...

Dan: You're a man after mine own heart.

Mike: I was in a meeting this morning..I'm coming, I'm coming. :)