dsn%umcp-cs%CSNet-Relay@sri-unix.UUCP (01/31/84)
From: Dana S. Nau <dsn%umcp-cs@CSNet-Relay>
From: Rene Bach <BACH@SUMEX-AIM.ARPA>
What are the evidences that the brain is a parallel processor? My own
introspection seem to indicate that mine is doing time-sharing. That is
I can follow only one idea at a time, but with a lot of switching
between reasoning paths (often more non directed than controlled
switching).
Does that mean you hold your breath and stop thinking while you're
walking, and stop walking in order to breathe or think?
More pointedly, I think it's incorrect to consider only
consciously-controlled processes when we talk about whether or not
the brain is doing parallel processing. Perhaps the conscious part
of your mind can keep track of only one thing at a time, but most
(probably >90%) of the processing done by the brain is subconscious.
For example, most of us have to think a LOT about what we're doing
when we're first learning to drive. But after a while, it becomes
largely automatic, and the conscious part of our mind is freed to
think about other things while we're driving.
As another example, have you ever had the experience of trying
unsuccessfully to remember something, and later remembering
whatever-it-was while you were thinking about something else?
SOME kind of processing was going on in the interim, or you
wouldn't have remembered whatever-it-was.dap@ihopa.UUCP (02/07/84)
If you consider pattern recognition in humans when constrained to strictly sequential processing, I think we are MUCH slower than computers. In other words, how long do you think it would take a person to recognize a letter if he could only inquire as to the grayness levels in different pixels? Of course, he would not be allowed to "fill in" a grid and then recognize the letter on the grid. Only a strictly algorithmic process would be allowed. The difference here, as I see it, is that the human mind DOES work in parallel. If we were forced to think sequentially abour each pixel in out field of vision, we would become hopelessly bogged down. It seems to me that the most likely way to simulate such a process is to have a HUGE number of VERY dumb processors in a heirarchy of "meshes" such that some small number of processors in common localities in a low level mesh would report their findings to a single processor in the next higher level mesh. This processor would do some very quick, very simple calculations and pass its findings on the the next higher level mesh. At the top level, the accumulated information would serve to recognize the pattern. I'm really speaking off the top of my head since I'm no AI expert. Does anybody know if such a thing exists or am I way off? Darrell Plank BTL-IH ihopa!dap
GCJ%edxa@ucl-cs.arpa (02/24/84)
From: JOLY G C QMA (on ERCC DEC-10) <GCJ%edxa@ucl-cs.arpa> To compare the product of millions of years of evolution (ie the human brain) with the recent invention of parallel processors seems to me to be like trying to effect an analysis of the relative properties of chalk and cheese. Gordon Joly.