Thread: Why do we sleep?

Sleep, Sleep, Sleep ! ... I have 3 yo Twin Boys ... WTF is sleep?

How do whales and dolphins sleep without drowning?

Observations of bottlenose dolphins in aquariums and zoos, and of whales and dolphins in the wild, show two basic methods of sleeping: they either rest quietly in the water, vertically or horizontally, or sleep while swimming slowly next to another animal. Individual dolphins also enter a deeper form of sleep, mostly at night. It is called logging because in this state, a dolphin resembles a log floating at the water's surface.


https://www.scientificamerican.com/a...s-and-dolphin/

Originally Posted by crackerjack101

or sleep while swimming slowly next to another animal.

I certainly sleep better next to her.
She's not an animal though.
Well, not precisely.

Originally Posted by David48atTD

Sleep, Sleep, Sleep ! ... I have 3 yo Twin Boys ... WTF is sleep?

How much sleep do you get?

How much do you need?

If I get 4 hours I'm OK. With assistance I'll sometimes get 6-7 which is great.

I thought sleep was a state of consciousness rather than an unconscious state.

I find it quite fascinating, why we need sleep and what dreams are about. I have many ideas but nothing of substance.

I agree with the notion that the more that's new in the previous days the more sleep I require. I can also get away with short sleep periods with 1 hour sleep giving another 2 hours awake but you get mentally tired quickly until you make the sleep up properly again.

I think there is more to it than simply repair, physically or mentally. I'd say it was far more for the brain than the rest of the body though. If I am down to 4 hours sleep a day when I can get more then I change routine or have a holiday. Routine change is more than changing route to work, which I do frequently to ensure I am not in auto...I catch the bus or cycle instead to make a big change.

If I wake up without dreaming then I go back to sleep until I have. I think it is important for me to dream.

What a stupid thread.

FUCK OFF!

Originally Posted by Cold Pizza

What a stupid thread.

FUCK OFF!

CP..... you're asleep. It's just a dream.

Do you dream?
Do you sleep?

Never mind it's not real. You're really dreaming.

Now follow the dream through and fall to your untimely, but generally well acknowledged, demise.

Silly little man that you are.

But "NO" you're awake, erect and proud.

Good for you.

The power in your urine engrossed penis leads you on.
If only it could be this good every day......

But then, sadly slipping, wetly weeping, the urine deflates and you're back to you same old withered little dick.

Ah well, there's always drink.

Carry on......

Originally Posted by crackerjack101

Years ago I picked up a paper back in some out of town second hand book shop.
It related the research of some bloke who'd spent a number of years investigating some remote tribe that believed that their dreams were reality and that there waking time was just something to be got through.

It was fascinating but I lost it. As I said it was years ago and I've no recollection of the title or the author.

I read that one or similar. Think I've read more than a couple of Amazon tribal accounts as well as the Aborigines, Native Americans and some pygmy tribe dreamers.

There's this study:

In the jungles of the Amazon live tribes to whom everyday reality is the dream. Hallucinations and dreams are the "real" reality, and the role of dreaming is thus very different from what it is in the West. There is a continuity between dreaming and waking. Dreaming is not just something that goes on during sleep.

Amazon Tribes and Collective Dreams with Marilyn Schlitz, PhD, by Wynn Free

I used to be a die hard conscious dreamer aka "lucid dreamer" as well as astral projection and other 'odd' practices. I could tell you lots of stories,...but....not this board.

Originally Posted by hick

Amazon Tribes and Collective Dreams with Marilyn Schlitz, PhD, by Wynn Free

Nice one. Thanks for the link.

Originally Posted by Cold Pizza

What a stupid thread.

FUCK OFF!

Cold Pizza off the scale, this is what your repo says when you try to copy the red... lol


There is a reason why you are the red repo leader....

Originally Posted by crackerjack101

If I get 4 hours I'm OK.

Ancient Chinese wisdom?

6 for a man
7 for a woman
8 for a fool.

An Unanswerable Question?
Scientists have explored the question of why we sleep from many different angles. They have examined, for example, what happens when humans or other animals are deprived of sleep. In other studies, they have looked at sleep patterns in a variety of organisms to see if similarities or differences among species might reveal something about sleep's functions. Yet, despite decades of research and many discoveries about other aspects of sleep, the question of why we sleep has been difficult to answer.

The lack of a clear answer to this challenging question does not mean that this research has been a waste of time. In fact, we now know much more about the function of sleep, and scientists have developed several promising theories to explain why we sleep. In light of the evidence they have gathered, it seems likely that no single theory will ever be proven correct. Instead, we may find that sleep is explained by two or more of these explanations. The hope is that by better understanding why we sleep, we will learn to respect sleep's functions more and enjoy the health benefits it affords.

This essay outlines several current theories of why we sleep. To learn more about them, be sure to check out the "Bookshelf" feature at the end of this essay. There you'll find links to articles by researchers who are studying this fascinating question.

Theories of Why We Sleep
Inactivity Theory
i_theories1.jpg
Arctic Fox at rest.

One of the earliest theories of sleep, sometimes called the adaptive or evolutionary theory, suggests that inactivity at night is an adaptation that served a survival function by keeping organisms out of harm’s way at times when they would be particularly vulnerable. The theory suggests that animals that were able to stay still and quiet during these periods of vulnerability had an advantage over other animals that remained active. These animals did not have accidents during activities in the dark, for example, and were not killed by predators. Through natural selection, this behavioral strategy presumably evolved to become what we now recognize as sleep.

A simple counter-argument to this theory is that it is always safer to remain conscious in order to be able to react to an emergency (even if lying still in the dark at night). Thus, there does not seem to be any advantage of being unconscious and asleep if safety is paramount.

Energy Conservation Theory
Although it may be less apparent to people living in societies in which food sources are plentiful, one of the strongest factors in natural selection is competition for and effective utilization of energy resources. The energy conservation theory suggests that the primary function of sleep is to reduce an individual’s energy demand and expenditure during part of the day or night, especially at times when it is least efficient to search for food.

i_theories2.jpg
Lions conserving energy after a meal.

Research has shown that energy metabolism is significantly reduced during sleep (by as much as 10 percent in humans and even more in other species). For example, both body temperature and caloric demand decrease during sleep, as compared to wakefulness. Such evidence supports the proposition that one of the primary functions of sleep is to help organisms conserve their energy resources. Many scientists consider this theory to be related to, and part of, the inactivity theory.

Restorative Theories
Another explanation for why we sleep is based on the long-held belief that sleep in some way serves to "restore" what is lost in the body while we are awake. Sleep provides an opportunity for the body to repair and rejuvenate itself. In recent years, these ideas have gained support from empirical evidence collected in human and animal studies. The most striking of these is that animals deprived entirely of sleep lose all immune function and die in just a matter of weeks. This is further supported by findings that many of the major restorative functions in the body like muscle growth, tissue repair, protein synthesis, and growth hormone release occur mostly, or in some cases only, during sleep.

Other rejuvenating aspects of sleep are specific to the brain and cognitive function. For example, while we are awake, neurons in the brain produce adenosine, a by-product of the cells' activities. The build-up of adenosine in the brain is thought to be one factor that leads to our perception of being tired. (Incidentally, this feeling is counteracted by the use of caffeine, which blocks the actions of adenosine in the brain and keeps us alert.) Scientists think that this build-up of adenosine during wakefulness may promote the "drive to sleep." As long as we are awake, adenosine accumulates and remains high. During sleep, the body has a chance to clear adenosine from the system, and, as a result, we feel more alert when we wake.

Brain Plasticity Theory
i_theories5.jpg
PET scan showing brain activity in a 20-year-old.

One of the most recent and compelling explanations for why we sleep is based on findings that sleep is correlated to changes in the structure and organization of the brain. This phenomenon, known as brain plasticity, is not entirely understood, but its connection to sleep has several critical implications. It is becoming clear, for example, that sleep plays a critical role in brain development in infants and young children. Infants spend about 13 to 14 hours per day sleeping, and about half of that time is spent in REM sleep, the stage in which most dreams occur. A link between sleep and brain plasticity is becoming clear in adults as well. This is seen in the effect that sleep and sleep deprivation have on people's ability to learn and perform a variety of tasks.

Bookshelf

Siegel JM. 2005. Clues to the functions of mammalian sleep. Nature. 437:1264-1271.
Porkka-Heiskanen T. 1999. Adenosine in sleep and wakefulness. Annals of Medicine. 31:125-129.
Frank MG. 2006. The mystery of sleep function: current perspectives and future directions. Reviews in the Neurosciences. 17:375-392.
This theory and the role of sleep in learning are covered in greater detail in Sleep, Learning, and Memory.

Although these theories remain unproven, science has made tremendous strides in discovering what happens during sleep and what mechanisms in the body control the cycles of sleep and wakefulness that help define our lives. While this research does not directly answer the question, "Why do we sleep?" it does set the stage for putting that question in a new context and generating new knowledge about this essential part of life.

For more about why we sleep, watch the video Why Sleep Matters and explore Consequences of Insufficient Sleep.

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This content was last reviewed on December 18, 2007

Harvard University
A resource from the Division of Sleep Medicine at
Harvard Medical School

Produced in partnership with WGBH Educational Foundation

http://healthysleep.med.harvard.edu/...hy-do-we-sleep

Originally Posted by crackerjack101

Scientists have explored the question of why we sleep from many different angles

Wonder if they ever considered we sleep because we have nothing else to do between the time bar closes and opens in the morning.

Originally Posted by VocalNeal

6 for a man
7 for a woman
8 for a fool.

12-14 for a Thai

Originally Posted by hick

Originally Posted by VocalNeal

6 for a man
7 for a woman
8 for a fool.

12-14 for a Thai

It must be said that the solitary experience I have of regularly sleeping with my wonderful wife is that if sleeping was an Olympic sport she'd be in with a chance.

Originally Posted by hick

In the jungles of the Amazon live tribes to whom everyday reality is the dream. Hallucinations and dreams are the "real" reality, and the role of dreaming is thus very different from what it is in the West. There is a continuity between dreaming and waking. Dreaming is not just something that goes on during sleep.

Quite fascinating....

Does anyone else have related dreams? Some of mine are like a TV soap. I have a semi somewhere in Cambridge that was broken into one night. I rent another place somewhere (I can't work out where in the UK) that I had renovated and you need to go down to the cellar to find your way upstairs, quite a bizarre little place. We still haven't told the Landlady we have renovated. I also live in a cul-de-sac similar to the first house I bought and am having an affair with the lady two doors down.

.. and people ask why I'm so grumpy first thing in the morning...

^ Yup always to do with airports, airplanes and problems. When I was a traveler it was always I did not get on my domestic flight but was heading back to the USA where I did not want to be. Now its passports, bags, tickets, passport control, twins, boarding passes, car rental, immigration......

Are Dreams an Extension of Physical Reality?

“I am real” said Alice (in Wonderland). “If I wasn’t real, I shouldn’t be able to cry.”

“I hope you don’t suppose those are real tears?” Tweedledum interrupted in a tone of great contempt.

Are Dreams an Extension of Physical Reality? | The Huffington Post

.....and we really find it necessary to scientifically explore the reasons behind whys and wherefores of this instinctively natural act.

Why? Whatta we attempting to conquer and harness?

It just is.

Originally Posted by thaimeme

.....and we really find it necessary to scientifically explore the reasons behind whys and wherefores of this instinctively natural act.

Why? Whatta we attempting to conquer and harness?

It just is.

With respect Jeff you "just is", but it doesn't stop us trying to work out why.

Sometimes my dreams are full of people I've never met. Seems to go against the theory that the purpose of dreaming is to review and filter gathered data, that efficiently occurs while the mind has little other demand on it.

I also tend to have very different types of dreams when I am sleeping somewhere other than my usual bed.