Why do we dream?

New research suggests dreaming isn’t pshochological at all.
*In a paper published last month in the journal Nature Reviews Neuroscience, Dr. J. Allan Hobson, a psychiatrist and longtime sleep researcher at Harvard, argues that the main function of rapid-eye-movement sleep, or REM, when most dreaming occurs, is physiological. The brain is warming its circuits, anticipating the sights and sounds and emotions of waking. *

An episode of BBC Horizon on dreaming pretty much say the same thing.

Me? I am still convinced when I have those crazy dreams I am visiting parallel universes.

I think it’s defragging .

A few years ago (and probably through the SDMB) I heard that the main function of dreams was to help your brain sort through which of the day’s events were going to be sorted into your longer-term memory and which one weren’t. I found that a lot more believable than theories about subconscious symbolism and that kind of thing, although it seems like the brain does borrow some material from your memory as it’s sorting or defragging or warming or whatever.

EDIT: The above theory is pretty much what the Times article is discussing and disputing. I couldn’t get the link to open at first, but I think I fixed it.

None of which explains why this morning I dreamed about watching a space shuttle take off and then hit a flying bus.

Your brain is “anticipating the sights and sounds and emotions of waking.” Didn’t you read the OP?

Oh, it’s going to be another one of those days.

I’d always heard it explained as “sorting through the day’s events.” I don’t know that I bought it entirely; I’ve always figured the brain, freed from having to process with most sensory input, was simply dealing with whatever appeared to need dealing with (processing issues that weighed on your mind, or perhaps, as has been suggested, “defragging” – or perhaps just sorting) in a manner that involved story-like, often surreal dreams.

I don’t know that I buy this “anticipating the sights and sounds and emotions of waking” stuff. Are they suggesting that the brain is kind of like a dog to whom someone enthusiastically said “Wanna go for a walk? Huh boy? Wanna go outside?” and now it’s wagging its tail and pacing and shimmying in anticipation by the front door thinking, “Oh boy oh boy, I can’t wait, master is going to take me for a walk outside! Outside! Woohoo! Oh comeoncomeoncomeonpleeeease hurry!”

I know we didn’t understand how the other explanation worked exactly, but it seemed more plausible. Dealing with the day’s events, or working out subconscious issues, or just rifling through fragments of thoughts and memories, makes some amount of sense. Why would the brain trigger strange dreams in “anticipating the sights and sounds and emotions of waking”? I can’t help but imagine the brain going, “Okay, let’s see what we need to do tomorrow here. Get up, good. Brush teeth, take a shower, grab some cereal and motor oil, kiss the Dalai Lama goodbye, grow a hundred feet and hop over the mesas of Arizona, pick up a birthday present for the office yak that it won’t like and subsequently result in my demotion to window licker, third class…”

I always fancied that we are “warm brained” in a sense like being warm blooded. We have to keep the brain going at some level of activity all the time. E.g., gotta be prepared if we wake up suddenly and need to chase off a cave bear.

So maybe the idea of “warming” isn’t so far off.

Everything ‘psychological’ is physiological. Do educated people really believe there is some abstract and spiritual core to the brain that goes beyond the physical realm?

Interesting view point !

I certainly don’t, but the complexity of thought, memory, perception, behaviour, etc. is so great, and so little understood, that it really needs be referred to in different terms from the mere physical. Maybe when our neurological comprehension of the brain is great enough, we can use purely physiological terms, but until then “psychological” seems as good a term as any, given that it’s the academic discipline that studies such things.

I’ve always felt that the brain, like the heart, cannot shut off when we sleep, or we will die. Dreams are just a by-product of the brain rattling on with no conscious control.

My armchair theory is that part of a dream’s function is to act as a psychological band aid for needs that aren’t being met in the awake life.

Like say if some one has no friends and they really need some one to talk to. Or if a cripple person really has an itch to get up and walk around, etc…

Basically a buffer to keep one from blowing ones brains out. Seriously, I’m not trying sound flakey or anything but who wants to live a life with no dreaming?

I know I don’t.