Sleep
Why do some people get really tired at night, when others are at their peak performance?
The human brain has 2 ways of regulating the sleep-awake cycle. The first is by external influence mainly light we see.
The other cycle is controlled by a chemical clock in our brains. This clock does not run exactly 24 hours, but it runs in a 23 hours to 25 hours cycle.
People who’s internal clock runs too fast – more like 23 hours – will get tired earlier but have no problem rising early.
Others have a slower internal clock – more like 25 hours – they might get very active at night but waking up before 11:00 is pure torture.
Over lifetime humans sync their internal clock more and more to earth days (24 hours) so most people will have a 23:47 internal clock or a 24:08 hours a day clock.
A couple of ways to reset your sleep cycle are:
- Light: seeing bright light tricks your brain to believe it is daytime and it should be better very awake. They do this to pilots in the Army to keep them awake for 36hours straight.
- Modafin il: take one of those pills and you will have the most productive and alert day of your lifetime. They also use those pills on Jet Pilots in the US-Army for their 36 hours shifts.
- Viagra: jup that stuff! It is known to reset the sleep cycle shortening the effect of a Jet-Lag for 50%. I don’t really know how one should administer the drug, before you sleep, when you wake up? Anyway in men it has a side effect that might not make it the perfect “take it before classes start” drug.
Why do we need to sleep at all?
This is basically a wild guess for any scientist and an even wilder guess for me:
The best explanation I read so far was that:
Animals sleep for maintenance purposes of their bodily functions, with a special focus on maintaining the brain.
During sleep we store new information we gathered during the day and disregard the useless info. Dreams are a crucial part of this.
During the REM (Rapit Eye Movement) sleep-phase we dream very intensely. Our brain can not really distinguish between imagination and reality therefore it shuts down every muscle in the body. This is important because imagine one of our ancestors dreaming of a successful hunt he had that day and his body would start running. Well given the fact that most of our ancestors slept on trees that would have granted a painful awakening, or no awakening at all. Holding still in your dreams is quite crucial. Only the eye muscle is allowed to move as we dream, therefore Rapit Eye Movement.
In the case you remember several dreams where you felt great danger coming towards you, but it was impossible for you to run because you were stuck, or paralyzed, that was your brain sending actual movement information to your muscles, who respond back: “No, we are shut of, we are not running!” Especially children suffer from this condition, because the brain jet has to learn that during sleep the lack of control over muscles is okay.
We also dream during our deep sleep phases (the opposite to the REM-sleep), but it is less a vivid story, but rather pieces of tough like: strange associations around the topic “Where did I put my mobile-phone?”
Every person dreams several times a night, if you don’t you are likely to be on sleeping pills (they suppress REM sleep), you are a psychopath, or on your way becoming one. Don’t worry if you can’t think of any dreams you have ever had, your brain just stored them in places you can not access = you forgot them. Normally people remember dreams only when they are awoken before the natural end of their sleep-cycle. Not remembering dreams = you most probably don’t wake up during the night + your alarm clock is not going off too early = Good for you!
Do other animals dream as well?
As it is not scientifically proven that all animals dream, I gathered the best evidence there is: ANECDOTAL Evidence:
What you can see here is a dog who obviously dreams of running and is body fails to shut his muscles down.
Goose have to be very aware of not being eaten so sleep is naturally a luxury they can not afford, fourtunately nature was so kind to grand them with an amazing ability: they sleep with one side of their brain, keeping the other one awake. Dolphins and whales would die if they would sleep because for breathing they have to go to the surface, so they apply the same trick, when the left side of their brain is a sleep, the right one is awake and vice versa.
The same thing is true for humans between the age of 6 and 25 years. It would impose a high risk for their well being to maintain full brain activity all of the time. During schooling one of the most important abilities one can gather is to put ones brain for up to 90% asleep while upholding the visual impression of being awake. This ability is not developed in Asian cultures.
Why do babies sleep so much?
Because their brain is so incredible active. Surprisingly a baby’s brain does not put most of its energy in building up new connections, but rather cutting the connections which are useless. Humans get born with 10times too many connections between all their brain areas. It really does not make sense to have a connection between the recognition of George Bush’s face and a tingling sensation in your left foot + the color blue. In order to save energy the brain cuts back all the useless stuff (like the recognition of George Bush’s face)
So babies make so many new connections in their brains + have to kill so many useless ones, and the time that works best is when they sleep.
The brain keeps on rebuilding itself until the age of 26. (Yes you get smarter until you are 26, from there on it goes downhill) Until that age is not uncommon to have a need for 10 hours of sleep per night. From there on 8 hours should do, on average. Once you hit 65 years of age 6 hours should be sufficient.
Until you hit the age of 26 you will suffer greatly from sleep deprivation. After that age it is usually not such a big problem anymore. Although being awake for 17 hours impairs your mental capacities as much as a blood alcohol level of 0.05% does. 24 hours being awake straight and your brain will be as slow as you would be at 0.1% blood alcohol. = Great news for every doctor on a 24hours shift. Yeah! [better you ask for a doctor who just had 3 beers and started work 1 hour ago, than the sober one who is in her 20th hour of her shift.]
People who continue using their brain a lot might have a need for a lot of sleep until their late years in life. [Einstein was famous for sleeping 9 hours every night]
Fun facts:
Humans sleep on average 2 hours less than other primates like chimps, baboons, chip monks. They sleep about 10 hours every day.
Also before the industrial revolution, records of people sleeping showed that during winter people slept on average 10 hours, but less during summer time. + one of the main disturbances for human sleep-cycle is the … INTERNET!
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