What causes dreams?

[Deadpangod3]

After having a dream where Jeb crash landed in my banished village, something has eluded me,

What causes dreams?

Does the brain partially wake up and hallucinate, or does it morph memories into other things and plays it back like a video tape?

Or something else?

[SargeRho]

Dreams happpen while the brain is processing the information it took up while you were awake. That can lead to some pretty funky imagery.

[astropapi1]

I spent about half an hour or so last night browsing this thread: http://www.reddit.com/r/LetsNotMeet

Needless to say, I had a bunch of nightmares and woke up in the middle of the night 3 times.

I hate nightmares.

[Deadpangod3]

Dreams happpen while the brain is processing the information it took up while you were awake. That can lead to some pretty funky imagery.

So does that mean if I were to play universe sandbox for a third of the day, crashing planets together, then landed an army fo kerbals on the mun in ksp for another third of the day, and built a city in banished for the final third of the day and went to sleep, I might end up with some weird dream where I live in a village where everyone are Kerbals and an alien planets going to crash into earth?

[cziken20]

So does that mean if I were to play universe sandbox for a third of the day, crashing planets together, then landed an army fo kerbals on the mun in ksp for another third of the day, and built a city in banished for the final third of the day and went to sleep, I might end up with some weird dream where I live in a village where everyone are Kerbals and an alien planets going to crash into earth?

Certainly, yes.

[vetrox]

Makes sense I spent all day playing banished...had some crazy multiplayer banished dreams. I also think I gay cos for some reason everyone had massive dongs!

[DonLorenzo]

Many things about dreams are not at all well understood. First and foremost their actual function, if any. Much the same with sleep; we know that it's necesarry, without it you will eventually go crazy and die. But thinking about it logically many things don't make too much intuitive sense, consider:

-Sleep is not for energy conservation. Energy requirements while sleeping are not significantly lower than when resting. The difference is about two peanuts worth of calories per night. One would say that that's not worth spending about a third of the time unconscious and defenseless.

-Sleep is not strictly necesarry to repair damage accrued in daytime activity. Simple rest would suffice for this. Also prolonged activity with no sleep doesn't seem to lead to accelerated physical breakdown or anything

-Sleep isn't quite necesarry to remain sane. I mean it is, but not on the order of sleep that we crave and get. Less would suffice.

Those are a few reasons that seem to make intuitive sense, but turn out to not ring so true. It is obvious that we do need sleep however. Why? No one is really sure but the prevalent thinking (at least a few years ago when I followed several courses in neurobiology) is that it has 'something to do with brain maintenance, filtering short term memories, converting some of them into long term and ditching the rest. Maybe.' It doesn't get much more specific than that really.

As a side note, I just had the stray thought that perhaps there could be some evolutionary merit to obligatory sleep in that it would force you to have a low profile and keep quiet at night, when you'd be most disadvantaged vs (some) predators. But that's just a thought of mine, no research behind that one.

Now on to dreams and why they might happen. Consider that your brain is one big 'consciousness-machine'. The world you see and perceive and interact with is there, but the way it exists in your consciousness isn't technically 'real'. Consider, there's a lot of information that you're omitting (anything your senses don't pick up) and a lot of information that's exaggerated. Even more information that's distilled, or is some kind of feedback from your own body. So our reality is a very selective distillation of a choice few input variables picked up by your sensors (eyes, ears, etc.). At night these sensors go offline or enter a suppressed mode (you're probably familiar with some real world sound, smell etc. entering your dreams) but your consciousness-machine doesn't quite shut down. One trick the brain has is to supplement information where it's missing. If you ever suffer eye damage, chances are that you'll see some spots for a few days and then not anymore. Your eye probably hasn't healed, instead your brain is just 'filling in the blanks'. Imagine that it does the same at night, when your senses are intentionally suppressed.

Combine that with the memory 'housekeeping' that's supposed to go on in your brain while sleeping and I think you have a pretty good reason/cause for dreaming. I don't think dreaming in and of itself serves a purpose, but rather it's a sideeffect of what's happening during sleep. I suppose you could turn this around and call dreaming the process by which the memory housekeeping happens, but I don't think we really understand enough about what's going on to be able to make that distinction either way.

That's sort of how I look at it

[cziken20]

But don't you feel weak when without sleep for a long time?

[Deadpangod3]

I've also heard somewhere that sometimes people can REALIZE AND KNOW that they're dreaming while its happening, and can wake themselves up if they want, or can alter the dream to their will, how does this happen?

And I heard "lucid dreaming" somewhere else, what does this mean?

[maccollo]

Recent studies suggest that the brain clear out toxins during sleep.

http://www.medscape.com/viewarticle/814070

Although it doesn't say if this is linked to the unconscious state we find ourselves in during sleep, I suspect there is a strong link.

It's also been strongly suggested in studies that the brain uses dreams to run simulations of everything from everyday experiences and things you are currently learning, to wacky outlandish things that "might happen". People who dream about the things they are learning about tend to learn faster. Initially when I first started playing KSP I found myself having multiple dreams about the intricacies of orbital mechanics.

So it would seem to me that dreams are basically the brain trying to be as productive as possible while it's disconnected from the outside world.

[vetrox]

Recent studies suggest that the brain clear out toxins during sleep.

http://www.medscape.com/viewarticle/814070

Although it doesn't say if this is linked to the unconscious state we find ourselves in during sleep, I suspect there is a strong link.

It's also been strongly suggested in studies that the brain uses dreams to run simulations of everything from everyday experiences and things you are currently learning, to wacky outlandish things that "might happen". People who dream about the things they are learning about tend to learn faster. Initially when I first started playing KSP I found myself having multiple dreams about the intricacies of orbital mechanics.

So it would seem to me that dreams are basically the brain trying to be as productive as possible while it's disconnected from the outside world.

this kind of makes sense to me. There have been times where a dream has helped me do so ething I couldnt do the previous day. For example, when I used to dance, there was one move I just couldnt do no matter how I tries to do it. One night after a heavy day of practicing I had a dream about doing that move. In the dream I had worked out how to do it, woke up, went downstairs and had a go at doing it the way I did in my brain.

another more recent thing I have noticed (whe going to bed straight after a night of gaming. Like straight after ie exit game turn computer off and go straight into the bed) My thoughts in bed and subsequient dreams will be thoughts about that particular game. If its a night of dota I will sleep and dream about 1 aspect of the game over and over. Its almost like the brain doesnt need to wrry about other functions and all it has lft to do is think about stuff. Like a computer cpu always needs to have input(see: system idle process).

Got to remember its not just humans that sleep, im fairly certain all mammals need sleep and have dreams. Dog owners will be aware of this. Sleep is inherintly needed to live but we are not 100% sure as to why and how.

A question I have is, why cant we sleep whenever we please? I may not be tired but sleep would be usefull (even if its just to pass time) why cant I just have a bank of hours that I can just fill with sleep? I may have worded that all very terribly

[DonLorenzo]

I've also heard somewhere that sometimes people can REALIZE AND KNOW that they're dreaming while its happening, and can wake themselves up if they want, or can alter the dream to their will, how does this happen?

And I heard "lucid dreaming" somewhere else, what does this mean?

You're in luck, you're talking to one of those magic dreamwalkers

Realizing that you're dreaming is not so crazy as you make it out to be. In essence it's no difference than realizing that your senses are fallible and things are not as they seem. Compare it to knowing that 'movies are not real'. Ofcourse while dreaming the realization is a bit more.. shall we say immersive. As to controlling the dream once you know it is in fact a dream, this isn't so outlandish a concept either. Consider these sort of figures: http://en.wikipedia.org/wiki/Spinning_Dancer where the big question is 'DO THEY SPIN CLOCK- OR COUNTERCLOCKWISE???' The answer is neither, since it's a 2d figurine. The perceived direction is controlled only by you. Once you realize this you may be able to 'control' which way the figurine appears to turn. There you have it, conscious control of the perceived world. Again, in a 'dreamworld' such control is a bit more immersive

Chances are that you've been lucid dreaming before, or even often, but you don't remember it. If you want to get into it (and it's something anyone can learn and practice, and it's pretty fun!) the first step is to learn remembering your dreams. There's no night where you don't dream. Doesn't exist. So for every night that you've got no recollection of a dream, you've forgotten one. If that was one where you were lucid and did all kinds of awesome stuff, too bad! One good trick is to keep a dream journal and record your dreams directly upon waking. It doesn't have to be page long prose, just a few keywords will suffice. You'll probably remember instances where you wake up from a vivid dream, remembering it all but having it slip away in but a few minutes. In this case, lie still in bed, move as little as possible while consciously repeating the memories to yourself over and over again until you're confident you'll make it to your dream journal without forgetting them.

Once you're consisently remembering your dreams, it's time to start getting lucid. The key to doing that is to somehow realize that you're dreaming, that the world you currently reside in is NOT in fact real. It sounds almost impossible (most outlandish things in dreams appear normal, after all) but fortunately there are a few tricks. An obvious one is jumping out of a window and seeing if you die, but for obvious reason that's not quite so good a test (I did do it once, and fortunately it did turn out to be a dream! Funnily enough I did then dream that I fell REALLY HARD and hurt myself good). Naturally what exactly works varies from person to person but here are a few things to get you started that work with about 90% of people.

-Machinery: any kind of technology often straight up doesn't work in dreams or performs other than it should. If you find yourself in a car that doesn't control as it should, facing a printer that will print nothing but water or in front of a fridge that contains only pick elephants of sugar you might be dreaming. Make it a point to consciously consider if the device you're handling is performing a reasonable function. If you wear a digital watch have a look at it every now and then, does the time make sense? If not (say: 7778:22 or a picture of a tree or something) then you might be dreaming!

-Consistency: In a dream things are more fluid than in reality. If you suspect you're dreaming, inspect something, look away and then inspect it again. Has it changed? You're probably dreaming. It helps if you try to mentally change something. For instance look at a bush and see normal leaves, look away and look back and try to fully expect observing square, yellow or otherwise outlandish leaves.

When you get more practiced it will usually be enough to just routinely think 'Am I dreaming?' If you can't recall a sequence of events leading up to what you're experiencing now, you might be! But in the beginning it's easier to go with 'tangible' tests. It might help to wear a digital watch of the kind that beeps every hour or so and make it a point to do a reality check then. Keep the watch by your bed as well and hopefully the beep qill cue the check whilst dreaming and.... bingo!

So, you've done one of these things and now you suspect you're dreaming, what now?! You need to make sure. Don't immediately start going nuts or what have you (yes, you're gonna go nuts). MAKE SURE first.

What I like to do is try a small supernatural feat. Say jumping up into the air and not falling down. No superman jumps, just hovering a few inches above the ground. Or try and change the ambient lighting by snapping fingers, trying to raise or lower the sun. Teleporting somewhere else. Spawning things or people. Blasting a fireball. Whatever floats your boat. If that works, then you're sure. Go nuts!

One thing I've noticed is that (for me at any rate) doing anything supernatural is very much like in the movie 'The Matrix'. It took me many times to learn how to consistently be able to fly and such. Along the way I faceplanted LOTS. You have to really really believe the things you want to do. Your mileage may vary obviously, but I've adopted one of two paradigms; One is of magic, where I draw mana from a pool inside me and use it to cast spells or do whatever and the other is more Sci-fi, where I pull up an overlay over the dream and do whatever I want to do through there. They sometimes work, sometimes not. Experiment.

If you do get into it, you'll learn to recognize in what stage of sleep you're in whilst dreaming. Some have the dream be more detailed, or lit/unlit. Some even have dreams with only partial sensory immersion. Again, your mileage may vary but I found that as I approached waking up my dream would 'lose resolution' or horizon. Meaning things would become blurry and bland and I couldn't see so far anymore. This could sometimes be partially fixed by concentrating or spinning really fast (a trick to change scenery, or teleport). Maybe I was postponing waking up, maybe not. Quite hard to tell really

One more note before I'll conclude this rambling post, and this is a good trick. It turns out that MANY MANY dreams, lucid or not, actually begin with a 'false awakening'. That is, you dream that you wake up. Make it a habit to do a reality check immediately after waking up ALWAYS. I can't count the times how often I've 'woken up' and it wasn't actually true. I've counted strings of fake wake-ups as long as fifteen. It's really the best, when you think you have to get up to go to work and it turns out that NOPE, still asleep, still got godmode LETS GO AGAIN. Yep. It's fun.

This might warrant a thread of its own but heck, it's sleep related

[Seret]

Does the brain partially wake up and hallucinate

Pretty much. Dreaming goes on during REM sleep, when your brain is closest to wakefulness. You go through several waves during a night's sleep, where you go from the REM state to other phases during which you don't dream. You only spend an hour or two dreaming in a night. A lot of it is to do with organising memory, if you're a student you'll find you remember things a lot better after a night's sleep, which is why all-nighters before exams are a bit pointless.

Edited February 24, 2014 by Seret

[Deadpangod3]

You're in luck, you're talking to one of those magic dreamwalkers

Realizing that you're dreaming is not so crazy as you make it out to be. In essence it's no difference than realizing that your senses are fallible and things are not as they seem. Compare it to knowing that 'movies are not real'. Ofcourse while dreaming the realization is a bit more.. shall we say immersive. As to controlling the dream once you know it is in fact a dream, this isn't so outlandish a concept either. Consider these sort of figures: http://en.wikipedia.org/wiki/Spinning_Dancer where the big question is 'DO THEY SPIN CLOCK- OR COUNTERCLOCKWISE???' The answer is neither, since it's a 2d figurine. The perceived direction is controlled only by you. Once you realize this you may be able to 'control' which way the figurine appears to turn. There you have it, conscious control of the perceived world. Again, in a 'dreamworld' such control is a bit more immersive

Chances are that you've been lucid dreaming before, or even often, but you don't remember it. If you want to get into it (and it's something anyone can learn and practice, and it's pretty fun!) the first step is to learn remembering your dreams. There's no night where you don't dream. Doesn't exist. So for every night that you've got no recollection of a dream, you've forgotten one. If that was one where you were lucid and did all kinds of awesome stuff, too bad! One good trick is to keep a dream journal and record your dreams directly upon waking. It doesn't have to be page long prose, just a few keywords will suffice. You'll probably remember instances where you wake up from a vivid dream, remembering it all but having it slip away in but a few minutes. In this case, lie still in bed, move as little as possible while consciously repeating the memories to yourself over and over again until you're confident you'll make it to your dream journal without forgetting them.

Once you're consisently remembering your dreams, it's time to start getting lucid. The key to doing that is to somehow realize that you're dreaming, that the world you currently reside in is NOT in fact real. It sounds almost impossible (most outlandish things in dreams appear normal, after all) but fortunately there are a few tricks. An obvious one is jumping out of a window and seeing if you die, but for obvious reason that's not quite so good a test (I did do it once, and fortunately it did turn out to be a dream! Funnily enough I did then dream that I fell REALLY HARD and hurt myself good). Naturally what exactly works varies from person to person but here are a few things to get you started that work with about 90% of people.

-Machinery: any kind of technology often straight up doesn't work in dreams or performs other than it should. If you find yourself in a car that doesn't control as it should, facing a printer that will print nothing but water or in front of a fridge that contains only pick elephants of sugar you might be dreaming. Make it a point to consciously consider if the device you're handling is performing a reasonable function. If you wear a digital watch have a look at it every now and then, does the time make sense? If not (say: 7778:22 or a picture of a tree or something) then you might be dreaming!

-Consistency: In a dream things are more fluid than in reality. If you suspect you're dreaming, inspect something, look away and then inspect it again. Has it changed? You're probably dreaming. It helps if you try to mentally change something. For instance look at a bush and see normal leaves, look away and look back and try to fully expect observing square, yellow or otherwise outlandish leaves.

When you get more practiced it will usually be enough to just routinely think 'Am I dreaming?' If you can't recall a sequence of events leading up to what you're experiencing now, you might be! But in the beginning it's easier to go with 'tangible' tests. It might help to wear a digital watch of the kind that beeps every hour or so and make it a point to do a reality check then. Keep the watch by your bed as well and hopefully the beep qill cue the check whilst dreaming and.... bingo!

So, you've done one of these things and now you suspect you're dreaming, what now?! You need to make sure. Don't immediately start going nuts or what have you (yes, you're gonna go nuts). MAKE SURE first.

What I like to do is try a small supernatural feat. Say jumping up into the air and not falling down. No superman jumps, just hovering a few inches above the ground. Or try and change the ambient lighting by snapping fingers, trying to raise or lower the sun. Teleporting somewhere else. Spawning things or people. Blasting a fireball. Whatever floats your boat. If that works, then you're sure. Go nuts!

One thing I've noticed is that (for me at any rate) doing anything supernatural is very much like in the movie 'The Matrix'. It took me many times to learn how to consistently be able to fly and such. Along the way I faceplanted LOTS. You have to really really believe the things you want to do. Your mileage may vary obviously, but I've adopted one of two paradigms; One is of magic, where I draw mana from a pool inside me and use it to cast spells or do whatever and the other is more Sci-fi, where I pull up an overlay over the dream and do whatever I want to do through there. They sometimes work, sometimes not. Experiment.

If you do get into it, you'll learn to recognize in what stage of sleep you're in whilst dreaming. Some have the dream be more detailed, or lit/unlit. Some even have dreams with only partial sensory immersion. Again, your mileage may vary but I found that as I approached waking up my dream would 'lose resolution' or horizon. Meaning things would become blurry and bland and I couldn't see so far anymore. This could sometimes be partially fixed by concentrating or spinning really fast (a trick to change scenery, or teleport). Maybe I was postponing waking up, maybe not. Quite hard to tell really

One more note before I'll conclude this rambling post, and this is a good trick. It turns out that MANY MANY dreams, lucid or not, actually begin with a 'false awakening'. That is, you dream that you wake up. Make it a habit to do a reality check immediately after waking up ALWAYS. I can't count the times how often I've 'woken up' and it wasn't actually true. I've counted strings of fake wake-ups as long as fifteen. It's really the best, when you think you have to get up to go to work and it turns out that NOPE, still asleep, still got godmode LETS GO AGAIN. Yep. It's fun.

This might warrant a thread of its own but heck, it's sleep related

Ok, how long would it take to do all this?

And would it be possible to bring things I think up in consciousness Ie some kind of massive city into this "dream world"? And if I were to like paint a building in this city, then wake up and dream again the next night would I come back to where I was or would it be like restarted?

Would I also be able to like be in one city like dream, then think myself in some other theme, and everything would change to that theme?

[Sillychris]

Dreams and sleep in general are not well understood in the scientific community. It is generally accepted that there are many factors and the phenomenon of dreams is complex.

However, one thing that is clear is that dreams are related to memories.

It is also interesting to note that learning seems to occur while we are sleeping. Studies have shown that individuals score better on memory tests after being allowed a night's rest instead of simply doing the test later that day.

My suspicion is that dreams are an unconscious analogue to reflecting and daydreaming.

[DonLorenzo]

Ok, how long would it take to do all this?

And would it be possible to bring things I think up in consciousness Ie some kind of massive city into this "dream world"? And if I were to like paint a building in this city, then wake up and dream again the next night would I come back to where I was or would it be like restarted?

Would I also be able to like be in one city like dream, then think myself in some other theme, and everything would change to that theme?

Those are things that are rather impossible to tell you, as I'm sure they vary a lot from person to person. I can tell you my experience though:

1. From deciding I wanted to do lucid dreaming to having my first lucid dream? less than a week I think. Motivation is a big part here. If it sounds great to you and you're looking forward to it, chances are it's gonna happen. This is one of those things that's really 'all in the mind'. Make yourself determined to do this. Decide before you go to bed 'I'm going to have a lucid dream tonight!' You can even decide in advance what it's going to be about. Does this work 100% No, you'll find most of these things don't. But they do work. Learning how to consistently remember dreams was very gradual for me. It just slowly got better and better. I'm sure I still forget many awesome adventures. One thing that does help a lot is getting enough sleep and not being too stressed out. Take your time to sleep. It sounds weird maybe but don't watch TV or be on the computer right up until the moment you go to bed. Tuck in, turn out the lights and take a few minutes to relax, maybe do some meditation where you focus on what and how you want to dream about. Then sleep.

2. As to what is possible, pretty much all you can imagine. Don't expect it to be like a game though where you turn on godmode and everything works the first time. Many things take practice, just like in the real world. It's just that they're pure mental skills and tricks with no real-world counterpart. Many of it will be completely new and won't come natural at all. Or it might. No way to tell really. For me it took lots of time to learn how to fly, and once I did I thought it was awesome. That was until I went bungee-jumping in the real world once, from that point on my dream-flights had the extra sensation of rushing air over my face and body. I suppose it got added because I experienced it once for real. Never did do that on purpose. It also varies from dream to dream. Sometimes I'll walk around like everything is a simulation, spawning people, shaping the world and doing things I couldn't very well write about in public. Other times I try that and it doesn't work. Yet other times the lucidity is on again/off again. I'll be lucid for a bit, but then something will happen in the dream and I'll forget that it's a dream. Then later I might 'snap out of it' again. Or not. It varies. Something that sometimes happens to me is that I'll get some sort of semi-lucidity. I know that I'm dreaming, but am still not really in control. The narrative goes on, but instead of active control I get a weird sort of precognition of a few seconds. I always wonder afterwards if the dream is 'decided' by some non-lucid part of me and I get a peek behind the scenes, or if the precognition is a fugasi and it's actually what's driving the narrative.

3. As for consistency from dream to dream, for me there's virtually none, apart from within myself. I'll remember tricks that worked and tricks that didn't. I'll try new stuff, or repeat old stuff that was fun. But the actual environments, characters, goings on and so forth are usually fresh every time. So what you're describing of building a vibrant and persistent dream world that you can visit and return to seems impossible to me. Yet if your memory is good and consistent enough perhaps you can do it. The only way I could imagine that is upon reaching lucidity to quickly rebuild that particular world. Then again it's not something I've tried, and as it's all in the mind anyway; if you decide that dream X is going to be permanent, who knows, it might be!

Returning to how long it would take you to 'learn' this stuff, that answer would range from instant to infinity. I'd hazard a guess that if you try and do those 'reality checks' often (find cues that happen a lot, say a background noise, passing through a door or something mundane like that and do one everytime you encounter that) you'll have your first lucid dream within days. It's different for everyone though and it might take longer. Chances are you'll be so excited when it first happens you'll immediately wake up due to the adrenaline surge. If that happens, do remember to do your post-wakeup check, it could be a fake wakeup!

Above all, see it as a fun thing to do whilst sleeping. Some people might tell you that 'you're messing with unknown and dangerous energies' or that you should 'watch out that you don't become lost and never wake up' or 'make sure not to kill yourself in the dream!!'. I've heard it all, and after ample experimentation I'm fairly sure there's no black hoodoo magic that's gonna kill you. It's just a fun trick. Like making the dancer spin counter- or clockwise.

I've tried to outline a rough spectrum of principles and tricks, there's a lot more nuance to be had in that regard. Just enter 'lucid dreaming' into google and find many forums, sites, books and even gadgets to help you lucid dream (there's apps that make your phone whisper 'You're dreaming!' every now and then. Or headbands that flash lights in your eyes. I've never dabbled but hey, could work!) One thing I found is to read as much about it and other people's experiences, gets you in the right mood and you might have your first tonight

[DonLorenzo]

Also, to stop derailing this thread completely, I've taken the liberty of doing a no-mod-power ghetto split and continuing the subject of lucid dreaming in its own thread here: http://forum.kerbalspaceprogram.com/threads/70721-Lucid-Dreaming?p=988979#post988979

[Camacha]

Sleep. Sleep causes dreams.

[DonLorenzo]

Sleep. Sleep causes dreams.

That's it, thread done!

[Awaras]

Sleep. Sleep causes dreams.

You are technically correct, the best kind of correct!

[Idobox]

The interesting thing is that even animals with very simple brains need some form of sleep.

The current mainstream view is that sleeping started as some sort of maintenance, flushing out toxins, repairing stuff, etc.

And then, given that you had this few hours a day where you were useless, other processes started to take place at the time. For example, in mammals, sleep is necessary for the immune system.

REM is also called paradoxal sleep because the EEG tells us you're awake, when you're not, and that's when you're dreaming. One hypothesis is that this step is a form of memory processing, but another hypothesis is that it's here for something else, but your brain doesn't like sensory deprivation and picks up random memories to keep occupied while that other process is under way.