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Medical Powers of The Brain

  1. Feb 19, 2007 #1
    The brain is supposed to be the most sophisticated piece of electronics. It can do things we can't dream with our current computers.

    I want t know how many of the worlds most sophiticated computers would it take to equal the output of our brain proccesing. Is our extreme computational power do to our internal programing or that we have far more neurons than chips have transistors>

    From what I heard todays most powerful cumputer doesn't have the brainpower of a housefly. Is it because neurons are so much smaller than transistors? Which is faster our brain or a computer? I'm guessing our brain has far more memory.
  2. jcsd
  3. Feb 20, 2007 #2
    Our brain has a pretty much infinite memory, considering our lifespans, there are estimates but there not exactly based on anything concrete, more guestimates. And no one entirely understands how the brain does what it does so effectively, or even how memories are stored, so we're pretty much in the dark at the moment - making good progress on finding out which parts of the brain do what, but not getting too far on exactly the processes involved.

    Computers are still pretty dumb when it comes down to it, but then evolution has had nigh on 4 billion years of dead ends and misadventures to end up with something this complex.

    Computers are useful for doing extraordinarily complex calculations quickly, they pretty much rule in this regard, and for storing vast amounts of easily accessible information without the need for vast warehouses of paper, or for doing mind numbingly repetitive experiments, or for sorting information etc. But for most other things, particularly those involving the creative process or abstract thinking, it's better to rely on the human mind, at least for now.

    Here's an interesting web site I found:-

    Bear in mind that by its nature such guesses are very speculative anyway, so this sort of theorising should not be taken as SCIENCE.

    http://www.totse.com/en/fringe/fringe_science/merkle1.html [Broken]


    Another paper, theorising on memory capacity.

    [tex]10^{8432} bits[/tex]

    Works out at


    That's quite a lot :smile:
    Last edited by a moderator: May 2, 2017
  4. Feb 20, 2007 #3
    10^15 bits at 10^16 OPS is the average information capacity of the brain among cog sci and AI researchers as pointed out above from http://www.merkle.com/brainLimits.html

    10^8432 bits is 10^8342 times as much information is in the observable universe down to quantum events! [10^90 bits] that paper was rather - strange- BTW the Beckenstien Bound limits the amount of information that can be contained in any region of space- configured as an ultradense ultrahot computer the 1 kg brain could only represent about 10^31 bits at 10^51 OPS- with every quantum observable spin of every particle harnessed as a bit http://www.edge.org/3rd_culture/lloyd/lloyd_index.html the amount of information that matter can represent has been well known and quantified since Maxwell and Boltzmann- I think Wang/Liu/Wang are basing their estimates on unbounded geometrical progressions of synaptic connections without taking into account the physical limits imposed by entropy- the real brain can only utilize the bits of it's 10^14-10^15 synapses- therefore at any given time the maximum amount of human memory must be configured as a percentage of those connections only-
    Last edited: Feb 20, 2007
  5. Feb 20, 2007 #4
    OK I'm going to go with these more realistic figures, but how many bits can the best supercomputer store, I wonder, that would be interesting, I had a lot of trouble trying to finding out I think I got 16 terabytes of on board memory, and 162 terabytes of hard drive space, but this was an old website.

    I think he's talking about the number of connections that could be formed given x amount of time, not the amount given x lifespan? Although I'm not sure...I doubt we're talking about quantum information here?

    I'm sure the complexity of the brain would make it a bit more than your figures, given we have no idea how the brain stores memory, but let's face it this is entirely in the realm of speculation.

    Don't forget we're not just talking about any given time, but also about the more long term store.
    Last edited: Feb 20, 2007
  6. Feb 20, 2007 #5
    Well, the top supercomputer in the world at the moment is the IBM BlueGene/L, which has the capability to operate at 280.6 teraflops [record]. It has 65,536 nodes, with two CPU's per node. There's 512MB of DDR RAM per node, so 65,536*512 = 32TB of memory. It also has a total of 806TB of hard drive space.
  7. Feb 21, 2007 #6

    I think you are on the right track- in fact I think they base their calculation on the possible states that a 10^15 bit system can have- which would be 2^10^15 possible configurations- [someone with a more powerful calculator than Google will have to tell us if 10^8432 is close to 2^1000000000000000 ]

    if so this is more than a potential memory capacity as the set of possible states would by definition include every active brain state of everyone who had ever lived in every moment of their lives- in addition to every possible moment of any human who could have lived in any universe- in addition to any and every possible mind state of any other human level intelligence either naturally evolved or artificially created in every possible universe- and that would still be only a tiny sub-set of the possible states of 10^15 bits- which would also include a great many more useless states that don't correspond to ANY form of intelligence- or even any form of definable matter-
    Last edited: Feb 21, 2007
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