>My take on dreams is that dreams are memes/ideas not subject to
>(very much) selection pressure from sensory input. Your eyes are
>closed, your limbs aren't moving, and so ideas can arise in your
>mind which normally would be outcompeted by more everyday ideas,
>which are supported by neural firing patterns from sensory
>information processing. These ideas, the output of your neural
>processing system, are then the only input from which to build the
>next set of outputs.
Complete and total speculation. I see this kind of guess work all the
time on the new-age newsgroups and even in the Christian talk rooms.
A very easy to find reference on dreams is the Sci American magazine
article for November 1990. It is titled "The Meaning of Dreams".
I will summarize this article for you, but let me strongly encourage
you to read the article anyways:
"Dreams may reflect a fundamental aspect of mammalian memory
processing. Crucial information acquired during the waking state may
be reprocessed during sleep."
Now for the real good part:
"Evidence that theta rhythm encodes memories during REM sleep may be
derived not only form neuroscientific studies but also from
evolution. The emergance of a neural mechanism to process memeory in
REM sleep suggests differences in brain anatomy between mammals that
have that aspect of the sleep cycle and those that do not. And in
fact, such differences clearly exist between the echidna and the
marsupials and placentals"
"The echidna has a large convoluted prefrontal cortex, larger in
relation to the rest of the brain than that of any other mammeal,
even humans. I believe it needed this huge prefrontal cortex to
perform a dual function: to react to incoming information in an
appropriate manner based on past experience and to evaluate and store
new information to aid in future survival. Withour theta rhythm
during REM sleep, the echidna would not be able to process
information while it slept...for higher capabilities to develop, the
prefrontal cortex would have to become increasingly large -- beyond
the capacity of the skull -- unless another brain mechanism evolved.
REM sleep could have provided this new mechanism, allowing memory
processing to occur 'off-line'. Coincident with the apparent
development of REM sleep in marsupial and placental mammals was a
remarkable change: the prefrontal cortex was dramatically reduced in
size."
"The nature of REM sleep supports this evolutionary argument..."
...which he then goes on to describe in great detail.
So you can see when I say that this idea that this computer is
"dreaming" or having "near death experiences" is pure hogwash. It is
meant only to sell the magazine you are reading and not inform you of
anything scientific.
>I don't have an opinion about whether dreaming is required for
>brains to function or not. BUT I think that the ideas and memories
>that you experience when dreaming can be thought of as memes
>interacting unfettered by most of the evidence that our senses
>usually provide.
The echidna did not need dreaming for it's mind or it's brain to
function. Human's need dreaming for the brain to function but the
mind that it contains could have survived without it. Of course the
brain would have to be much much larger than what it is now to
perform the same funtions that is does now.
Therefore, this is evidence that dreaming cannot be thought of as
memes interacting unfettered by most of the evidence that our sense
usually provide.