Why do we sleep?
Discussion
Oakey said:
Biscuit dunker said:
Some good suggestions but doesn't really answer why.
Without it your brain goes into meltdown and you'll start hallucinating... horrible, horrible hallucinations. It's believed that dolphins don't actually sleep but shut down bits of their brain - how come we're not at the very least doing something similar? I don't need my entire brain to sit and watch the tv the OH forces me to watch every evening....
Art0ir said:
Ray Luxury-Yacht said:
As a biology and medical student (with a bit of mental and physical psychology chucked in), I have studied this a bit - and after doing a fair bit of research, the simple answer is this:
Human sleep is basically for the brain only.
Yes, I agree that there are physiological repairs and maintenance that also occur within the rest of the body during sleep too - but mainly because the conditions are favourable to do so during sleep - i.e. lack of movement, low energy demands etc...
But most human biologists agree that the physical body would be fine to be awake and moving constantly, without sleep (but not necessarily without some rest, obviously). It would just mean that the usual repairs and maintenance within the body's systems would occur a little slower than with sleep.
Sleep appears to allow our complex brains to re-organize, re-boot and congnitively prepare for the next period of wakeful exposure. The difference between us and other mammals that don't necessarily sleep for as long as we do, or sleep in part is that our brains are the only ones on the planet that have cognitive consciousness and the ability to be self-aware and make decisions involving many complex factual and emotional reasoning.
No other living things do so, obviously.
If you have a Google around, there are lots of studies and experiments into sleep factors, and how lack of it affects our cognitive ablility - plus explainations about how the rest of our bodies could function without it.
Did you ever read into the training yourself to skip the "useless" bits of sleep? I think it's the Sony CEO that only sleeps 2 or 3 hours a night because he goes straight to REM (?)Human sleep is basically for the brain only.
Yes, I agree that there are physiological repairs and maintenance that also occur within the rest of the body during sleep too - but mainly because the conditions are favourable to do so during sleep - i.e. lack of movement, low energy demands etc...
But most human biologists agree that the physical body would be fine to be awake and moving constantly, without sleep (but not necessarily without some rest, obviously). It would just mean that the usual repairs and maintenance within the body's systems would occur a little slower than with sleep.
Sleep appears to allow our complex brains to re-organize, re-boot and congnitively prepare for the next period of wakeful exposure. The difference between us and other mammals that don't necessarily sleep for as long as we do, or sleep in part is that our brains are the only ones on the planet that have cognitive consciousness and the ability to be self-aware and make decisions involving many complex factual and emotional reasoning.
No other living things do so, obviously.
If you have a Google around, there are lots of studies and experiments into sleep factors, and how lack of it affects our cognitive ablility - plus explainations about how the rest of our bodies could function without it.
Couldn't it even be more basic than everything suggested thus far.
When we were evolving over the last millions of years there was nothing to do during the night time.
The world out there is really, really, surprisingly dark at night when the lights properly go out during a power cut for instance.
Difficult to do anything constructive when you can't see your hand infront of your face!
When we were evolving over the last millions of years there was nothing to do during the night time.
The world out there is really, really, surprisingly dark at night when the lights properly go out during a power cut for instance.
Difficult to do anything constructive when you can't see your hand infront of your face!
Piersman2 said:
Couldn't it even be more basic than everything suggested thus far.
When we were evolving over the last millions of years there was nothing to do during the night time.
The world out there is really, really, surprisingly dark at night when the lights properly go out during a power cut for instance.
Difficult to do anything constructive when you can't see your hand infront of your face!
Our natural sleeping pattern is 2 sleeps a day not one.When we were evolving over the last millions of years there was nothing to do during the night time.
The world out there is really, really, surprisingly dark at night when the lights properly go out during a power cut for instance.
Difficult to do anything constructive when you can't see your hand infront of your face!
Biscuit dunker said:
x2.
But seriously, surely being able to stay awake and fully alert is an evolutionary advantage over needing to sleep to stay alert when awake?
No, because once upon a time calories were precious and starvation would have been a common killer. Being awake and alert uses up far more calories than being asleep and given that we can do nothing useful at night in the old days, then sleeping would be a major advantage.But seriously, surely being able to stay awake and fully alert is an evolutionary advantage over needing to sleep to stay alert when awake?
Almost like a nightly hibernation
annodomini2 said:
Piersman2 said:
Couldn't it even be more basic than everything suggested thus far.
When we were evolving over the last millions of years there was nothing to do during the night time.
The world out there is really, really, surprisingly dark at night when the lights properly go out during a power cut for instance.
Difficult to do anything constructive when you can't see your hand infront of your face!
Our natural sleeping pattern is 2 sleeps a day not one.When we were evolving over the last millions of years there was nothing to do during the night time.
The world out there is really, really, surprisingly dark at night when the lights properly go out during a power cut for instance.
Difficult to do anything constructive when you can't see your hand infront of your face!
d. 
blindswelledrat said:
No, because once upon a time calories were precious and starvation would have been a common killer. Being awake and alert uses up far more calories than being asleep and given that we can do nothing useful at night in the old days, then sleeping would be a major advantage.
Almost like a nightly hibernation
Now that, if it's true, actually makes sense in evolutionary terms - I hadn't really thought of it that way. Though, thinking about it, would it not be more efficient to be able shut down and save energy by choice rather than as an absolute necessity as is the case with sleep?Almost like a nightly hibernation
Piersman2 said:
annodomini2 said:
Piersman2 said:
Couldn't it even be more basic than everything suggested thus far.
When we were evolving over the last millions of years there was nothing to do during the night time.
The world out there is really, really, surprisingly dark at night when the lights properly go out during a power cut for instance.
Difficult to do anything constructive when you can't see your hand infront of your face!
Our natural sleeping pattern is 2 sleeps a day not one.When we were evolving over the last millions of years there was nothing to do during the night time.
The world out there is really, really, surprisingly dark at night when the lights properly go out during a power cut for instance.
Difficult to do anything constructive when you can't see your hand infront of your face!
d. Du1point8 said:
Art0ir said:
Ray Luxury-Yacht said:
As a biology and medical student (with a bit of mental and physical psychology chucked in), I have studied this a bit - and after doing a fair bit of research, the simple answer is this:
Human sleep is basically for the brain only.
Yes, I agree that there are physiological repairs and maintenance that also occur within the rest of the body during sleep too - but mainly because the conditions are favourable to do so during sleep - i.e. lack of movement, low energy demands etc...
But most human biologists agree that the physical body would be fine to be awake and moving constantly, without sleep (but not necessarily without some rest, obviously). It would just mean that the usual repairs and maintenance within the body's systems would occur a little slower than with sleep.
Sleep appears to allow our complex brains to re-organize, re-boot and congnitively prepare for the next period of wakeful exposure. The difference between us and other mammals that don't necessarily sleep for as long as we do, or sleep in part is that our brains are the only ones on the planet that have cognitive consciousness and the ability to be self-aware and make decisions involving many complex factual and emotional reasoning.
No other living things do so, obviously.
If you have a Google around, there are lots of studies and experiments into sleep factors, and how lack of it affects our cognitive ablility - plus explainations about how the rest of our bodies could function without it.
Did you ever read into the training yourself to skip the "useless" bits of sleep? I think it's the Sony CEO that only sleeps 2 or 3 hours a night because he goes straight to REM (?)Human sleep is basically for the brain only.
Yes, I agree that there are physiological repairs and maintenance that also occur within the rest of the body during sleep too - but mainly because the conditions are favourable to do so during sleep - i.e. lack of movement, low energy demands etc...
But most human biologists agree that the physical body would be fine to be awake and moving constantly, without sleep (but not necessarily without some rest, obviously). It would just mean that the usual repairs and maintenance within the body's systems would occur a little slower than with sleep.
Sleep appears to allow our complex brains to re-organize, re-boot and congnitively prepare for the next period of wakeful exposure. The difference between us and other mammals that don't necessarily sleep for as long as we do, or sleep in part is that our brains are the only ones on the planet that have cognitive consciousness and the ability to be self-aware and make decisions involving many complex factual and emotional reasoning.
No other living things do so, obviously.
If you have a Google around, there are lots of studies and experiments into sleep factors, and how lack of it affects our cognitive ablility - plus explainations about how the rest of our bodies could function without it.
Surely this question assumes that we have finished evolving?
As stated earlier, there's the possibility that there was little to do during the nighttime in times gone by, and the many years of evolution allowed for that.
The ability to work throughout the night, easier communication to other timezones (working during daylight will always be preferable) has not been around very long. Maybe over the next X hundred / thousands of years there will be numerous changes in our brains, this being one of them.
Evolution is also based upon survival, maybe there is a perfect balance at the moment of efforts required in order to survive well, and therefore the additional hours are surplus to requirements.
Regardless, I'm bloody glad of it as it allows me to keep my sanity throughout the stresses of the outside world! (maybe that's why it's been evolved to be so).
As stated earlier, there's the possibility that there was little to do during the nighttime in times gone by, and the many years of evolution allowed for that.
The ability to work throughout the night, easier communication to other timezones (working during daylight will always be preferable) has not been around very long. Maybe over the next X hundred / thousands of years there will be numerous changes in our brains, this being one of them.
Evolution is also based upon survival, maybe there is a perfect balance at the moment of efforts required in order to survive well, and therefore the additional hours are surplus to requirements.
Regardless, I'm bloody glad of it as it allows me to keep my sanity throughout the stresses of the outside world! (maybe that's why it's been evolved to be so).
i think there are lots of inter-related reasons
if you are not equipped to be active in the dark (e.g. eyesight), then it's better to conserve as much energy as possible during the night - sleep.
if you have a complex nervous system/brain sleep is important for the maintenance and development of that.
if you are not equipped to be active in the dark (e.g. eyesight), then it's better to conserve as much energy as possible during the night - sleep.
if you have a complex nervous system/brain sleep is important for the maintenance and development of that.
Simpo Two said:
vinnie83 said:
Surely this question assumes that we have finished evolving?
vinnie83 said:
Maybe over the next X hundred / thousands of years there will be numerous changes in our brains...
Only one of those can be true...(and I say that as a very very distant relative of Darwin!)
I would imagine that any animal constantly evolves to meet its surroundings... If I had to bet either way, I would say that humans still have a long way to go!
Ah yes, I see. As long as there is selection there will be evolution. However now that we are all 'civilised' (as opposed to clubbing each other to death with dinosuar bones), the selection forces are different. For example, if you pay chavs to breed, the proportion of chavs in the population will rise. This was not foreseen by the idealists in 1945.
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