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Brain's Cache Memory Found 531

Shipud writes "Electrical activity in a single section of the brain has been linked to very short-term working memory, as is reported at Nature. Very short-term working memory capacity is thought to be related to intelligence. In the same way that a larger cache speeds processing time, people with a greater capacity for holding images in their heads are expected to have better reasoning and problem-solving skills. The localization of this ability is a surprising finding, as until now it was believed that STWM was diffused throughout the cortex, rather than localized."
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Brain's Cache Memory Found

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  • Great (Score:5, Funny)

    by FS1 ( 636716 ) on Friday April 16, 2004 @04:37AM (#8879030)
    Is this going to lead to benchmarking people?

    Employer: I'm sorry sir you don't have a big enough cache for our needs. We are going to have to let you go.
    Employee: Man this blows i would be really upset but i forgot what you just said.
    • Re:Great (Score:5, Funny)

      by Anonymous Coward on Friday April 16, 2004 @04:45AM (#8879062)
      so we can coin new phrases like:
      He's got the brain-cache of a Celeron!
      I'm feeling pretty Celeroned after that party last night!
      • by Gadgetfreak ( 97865 ) on Friday April 16, 2004 @08:03AM (#8879675)

        Sgt. Friday: "Are you sure this is the woman you saw in the post office?"
        Burns: "Absolutely! Who could forget such a monstrous visage? She has the sloping brow and cranial bumpage of the career criminal."
        Smithers: "Uh, Sir? Phrenology was dismissed as quackery 160 years ago."
        Burns: (measuring Smither's head) "Of course you'd say that... you have the brainpan of a stagecoach tilter!"

    • Re:Great (Score:2, Funny)

      by Anonymous Coward
      On the downside the replacement with more cache will cost 10 times more.
    • It won't be long until we see some overclocking utilities now.
      • Re:Great (Score:3, Interesting)

        by phyruxus ( 72649 )
        >>It won't be long until we see some overclocking utilities now.

        Parent may have been in jest, but I think comment should be modded interesting: The brain of an infant is mostly spare parts (some of the brain is hardwired but most of it is just "extra" brain cells (plus we barely understand the brain compared to how much we understand the body.. b.i.d.)) therefore perhaps we really could develop a training regimen which would allow the "cache" to appropriate more "hardware" (neurons) to effectively "u

    • Re:Great (Score:5, Interesting)

      by KaiLoi ( 711695 ) on Friday April 16, 2004 @04:56AM (#8879121)
      Yea.. I'm sorry but the first thing I thought when I saw this article was : "Ok.. so what do I have to take to make this bigger?"

      However what I suspect is that while they have found the portion of the brain that helps with problem solving actual intelligence is linked to far more factors than one area

      For example someone who has a small "cache" area and can't hold too many images at once may be able to work round this with a greater long term storage capacity which they can draw on.

      It's all well and good to be able to cache images and information quickly. doesn't help you if you're outputting onto a 10 meg Hard drive.
      • Re:Great (Score:5, Insightful)

        by FS1 ( 636716 ) on Friday April 16, 2004 @05:02AM (#8879147)
        Now im going to use a somewhat tried and true comparison here just try and follow me.
        Everyone knows that both the P4 and the Celeron share the same architecture ( Intelligence ? ), but vary only in their cache size. Now run a comparison using any application have you and see which one can do the task faster.
        It is the size of the cache that determines intelligence in this case. The cache size just inhibited the ability of the intelligence to work as quick as it could.
        • no (Score:3, Funny)

          by RMH101 ( 636144 )
're assuming that the brain processes information like a P4. this isn't the case!
      • Re:Great (Score:5, Funny)

        by O2n ( 325189 ) on Friday April 16, 2004 @05:24AM (#8879219) Homepage
        first thing I thought when I saw this article was : "Ok.. so what do I have to take to make this bigger?"
        Ok, people, brace for the "ENLARGE your cache by 3" in one month!!!" spam...
      • Re:Great (Score:5, Funny)

        by Lord_Dweomer ( 648696 ) on Friday April 16, 2004 @08:14AM (#8879731) Homepage
        Exactly, first thing I thought was "how big is mine, and how could I upgrade?" While long term memory storage may be a ways off (like the kind in Johnny Pneumonic), but this looks much more feasible in the short term. God, just wait though till parents get their hands on this. Think kids have pressure to get into school now and be the absolute brightest? You ain't seen nothing till you see a child lugging around a briefcase everywhere and when asked to explain he says "its an upgrade for my brain cache".

        • You ain't seen nothing till you see a child lugging around a briefcase everywhere and when asked to explain he says "its an upgrade for my brain cache"

          Your modern child already carries around a brain-cache upgrade. He calls it a notebook.

          The more advanced (creepy alphas, we don't hang around with them) carry PDAs.

          Of course, an aid can become a crutch. I recall a story told me by a friend of mine. Her grandmother, an unlettered immigrant from Lithuania, has, perforce, a phenomenal memory, never n

      • Re:Great (Score:5, Interesting)

        by skidoo2 ( 650483 ) on Friday April 16, 2004 @09:00AM (#8879943)
        Yeah, but we (perhaps instinctively?) developed aeons ago inexpensive utilities for augmenting long-term storage. Like writing.

        Short-term storage is a little more difficult to augment effectively because of the time factor. So maybe this discovery will actually drive the first brain mods. The evolutionary incentive is surely there.

        Let's just hope Sony or Apple doesn't start off the race with some terribly marketed, proprietary, yet superior technology that will be forever relegated to the basement vault where they keep dinosaurs such as Betamax.
      • Re:Great (Score:3, Funny)

        by rjelks ( 635588 )
        No offense, but that sounds like something someone would say if they had no level 2 cache.
      • by lildogie ( 54998 )

        If you're reading this, you know that men with small short term memory don't get ahead....
    • Does scientific Confirmation-Bias exist in the Hippocampus too?
      The peer review of this "OLD" psychological ability to "chunk" information for 7 +-2 episodic memories is not a problem solving based semantic thought process.
      What about parallel distributed processing models of the brain, perhaps this irresponsible researcher had a case study that defied all statistics and the 35 years of PET scans, MRI data, and REAL SCIENTIFIC STUDY. Note too that the "chunking" ability is not a static number, and has been pr
    • Man this blows i would be really upset but i forgot what you just said.

      A mind like that is to be envied.

    • Great? (Score:4, Funny)

      by Sleeper ( 7713 ) on Friday April 16, 2004 @05:27AM (#8879237)
      May be... But still I'm afraid that the size of your STWM is not going to impress your girlfriend.

    • Re:Great (Score:5, Interesting)

      by Azathfeld ( 725855 ) on Friday April 16, 2004 @05:31AM (#8879254)
      Is this going to lead to benchmarking people?

      That's actually an interesting thought. There are a lot of complaints about whether or not IQ tests are viable; IQ is even usually defined as the ability to do well on IQ tests. If the "performance bottleneck" of the human has been found, it may be possible to develop definitive, or at least useful, tests for actual intelligence.
    • Re:Great (Score:4, Funny)

      by Averron ( 677873 ) on Friday April 16, 2004 @06:23AM (#8879381)
      Ah yes, my brain is only running at 1600, but its performance rating is 2500+++!!! So there!
    • Already Here. (Score:4, Interesting)

      by boobsea ( 728173 ) on Friday April 16, 2004 @07:40AM (#8879594) Journal
      Scams in the forms of SAT/ACT tests and IQ tests.

      All of these are used to sort people, suposedly people with higher scores on these are somehow smarter, despite obvious instances of people who do not perform according to their 'score'.
  • by VValdo ( 10446 ) on Friday April 16, 2004 @04:37AM (#8879031)
    Does the article mention anything about expansion modules? I'd read it myself, but I can't remember what we're talking about here...

    What was I saying again?

    • by Burpmaster ( 598437 ) on Friday April 16, 2004 @04:43AM (#8879052)

      More? Come on, 640k ought to be enough for anybody!

    • Stem Cells (Score:3, Interesting)

      by qewl ( 671495 )
      I wonder what would happen if they just injected some stem cells around there?
      • Re:Stem Cells (Score:5, Interesting)

        by Stopmotioncleaverman ( 628352 ) on Friday April 16, 2004 @07:17AM (#8879521)
        I'm studying for a degree in genetics at the moment and I was interested to hear your question.

        Simply injecting stem cells there wouldn't really do a lot .Whilst stem cells are what is known as 'pluri/toti-potent' - that is, they can give rise, under different conditions, to many (or in some cases all) types of bodily cell, (e.g. liver, spleen, pancreatic, brain neuron etc etc.), they need the correct stimulus, in the form of the correct chemical environment, to make them differentiate into that sort of cell.

        Increasing the size of that area would probably make some sort of difference to the STWM, so we'd need to approach it in a way that caused us to end up with not only more cells there, but more cells that actually perform the correct function there, and that tie in with the existing lot of cells. No use having a ball of cells of the right type there that just grow into a new mass. In fact, that's what we call a tumour. Never good in the middle of your head :P

        Needless to say, that's not as easy as it sounds. You'd need to get some stem cells, and discover what is the exact stimulus that makes them, in the developing embryo, mature into 'STWM cells'. Since I think we can likely assume that your 'brain cache' doesn't grow in size throughout life (or you'd get progressively more logical and have an improved short term memory as you got older), we can also probably guess that this area is fully developed at birth and therefore the only place the correct environment for this differentiation would be likely to occur is in the developing foetus.

        Which means that you'd have to take some developing foetuses apart to try and localise the correct chemical environment. And then you get into legal/ethical fluff. Currently, there's no way you'd get permission to take foetuses to bits to improve some adult's short term memory. Maybe in times to come, we'll be able to co-localise these factors and chemical environment electronically, or with some sort of prenatal scan. Until then, I'd think that stem cell therapy is unlikely to work correctly.
        • Re:Stem Cells (Score:3, Interesting)

          by DrKayBee ( 769192 )
          Neuronal networks work on their degree of interconnectivity. I can bet there's enough cells in our brain, but their activity is limited by how their connections are put together.

          There is a part of behaviorial science that says "you get better at solving the problems that appeal to you, and the better you are, the more appealing the problems become", of course most /.ers know that already!

          On RTFAing, I have this feeling that the region of the brain under discussion is not the cache memory but rather the
        • It seems that some of the brain's activity is devoted to INHIBITING functions. Sometimes people with limited brain functions display extraordinary capabilities, i.e. called idiot-savants- because regular inhibition is missing. A second example is that people with intentional or accidental lobotemies (e.g. press secretary James Brady) have trouble controling their emotions. Photographic memory may not be due to improved memory, but defective *forgetting*. So my hypothesis is that this memory cache could be i
    • by Averron ( 677873 ) on Friday April 16, 2004 @05:20AM (#8879208)
      No expansion modules, sorry. Lucky for you, all you have to do is exercise it, promoting the growth of neural pathways in this area. Try sitting around thinking of very complex images or something. Maybe the old oranges trick -- think of one orange, then think of two, five, ten, thirty, fifty, 100, 1000, a million. If I recall correctly, you can see some interesting results with this -- as you get higher, people begin to group the oranges in order to be able to comprehend them all at once. Usually people see a truck carrying oranges when they reach a million, and a barrel at a thousand. Try viewing as many of them as you can without grouping.
      • by Lumpy ( 12016 ) on Friday April 16, 2004 @07:07AM (#8879494) Homepage
        That method does not work as well as recursive detail...

        Think of one orange, now think of that orange in minute detail, focus on the pores, the cut stem, focus on that image, now while focusing on that image focus on the SMELL of that orange, then the feel of it...

        the most important part is not getting stuck in 2 or 3 dimensional memory.. but 5 dimensions... you must exercize your memory with all your sensory inputs.

        usualkly the people that have a better recall will recognize this trick...

        think of a rose.

        those of you that can not only see it and it's texture but smell it have the higher processor cache... those of you that can also feel the stem have the most processor cache.
    • Bender: "So what's your problem?"
      Sinclair 2k: "Not enough hmmmuh..."
      Bender: "Memory?"
      Sinclair 2k: "Oh great. Now I remember that word but I forgot my wife's face."
  • by Buck2 ( 50253 )
    What are we linking to?

    I always thought prefrontemporal was short-term. Is this anything new?
  • images (Score:4, Funny)

    by Anonymous Coward on Friday April 16, 2004 @04:41AM (#8879045)
    a greater capacity for holding images in their heads

    good news for pr0n hounds.
    too bad it's addicting

  • just short-term memory?

    Then the cache gets written to the hard drive for permanent storage so after you turn yourself off (in bed), the data is there the next day.
  • Man vs machine (Score:4, Interesting)

    by romit_icarus ( 613431 ) on Friday April 16, 2004 @04:43AM (#8879053) Journal
    It's interesting how we use rudimentary digital computing analogies to explain the workings of our brain. Like in most theories, I suppose one can extend this analogy only to a certain extent. Which, in this case, shouldn't be suprising considering how comlex the brain is...
    • Re:Man vs machine (Score:5, Interesting)

      by powerlinekid ( 442532 ) on Friday April 16, 2004 @04:54AM (#8879102)
      Its always been like this.

      Now a days, we explain it through digital computers. Before that was electrical systems. Before that mechcanical systems, I would imagine fluid systems, etc.

      We seem to always use our most modern technology as an analogy for things that are still a little outside our grasp (such as the brain). In 20 years we may be describing the brain in terms of nano-tech.
    • Re:Man vs machine (Score:3, Interesting)

      by trentblase ( 717954 )
      We also use biological analogies to explain the workings of digital systems. How many times have you told someone that the computer is "thinking" or that it has a "virus". This kind of thing goes both ways, I think it's mostly out love for analogy in general.
  • No Monkeys for RAM No Monkeys for RAM This DDRRAM has not been tested on animals
  • by Metallic Matty ( 579124 ) on Friday April 16, 2004 @04:47AM (#8879071)
    Perhaps this explains why my head gets extremely hot when I do my Calculus exams.
  • Looks like... (Score:4, Interesting)

    by Black Parrot ( 19622 ) on Friday April 16, 2004 @04:48AM (#8879074)

    Interestingly, both groups of researchers were working strictly with visual memory. I wonder whether the working memory used by programmers, mathematicians, etc. will be in the same place, or a different area altogether?

    And what about the famous "magic number", 7 +/- 2? These people seem to be offering 4 +1/-2.

    • Re:Looks like... (Score:5, Interesting)

      by DunbarTheInept ( 764 ) on Friday April 16, 2004 @04:56AM (#8879117) Homepage
      I don't know about you, but when I program, I *do* think visually about it. It's really hard to describe exactly how, but to me, writing in a programming language "feels" more akin to drawing a picture than writing an essay.

      I don't think all programmers approach the task using the same kind of intelligence.

      I think it would be interesting to check different disciplines against each other, but programming is a bit too all-encompassing to be nailed down to just one kind of intelligence. It's partly language thinking, partly spatial thinking, partly mathematical thinking, a little bit of art, etc...
      • Re:Looks like... (Score:5, Interesting)

        by Kjella ( 173770 ) on Friday April 16, 2004 @06:09AM (#8879350) Homepage
        I don't know about you, but when I program, I *do* think visually about it. It's really hard to describe exactly how, but to me, writing in a programming language "feels" more akin to drawing a picture than writing an essay.

        When I program, I hardly think visually at all. Then I've usually mapped a clear sequence 1. 2. 3. 4. that'll get me from A to B. Even if it doesn't work right, it's mostly just adding, subtracting or reorganizing the steps, in a purely linear fashion.

        When I design, I primarily think in 3D. Or at least, more than 2D, I don't think in the form of trees and object hierarchies, but more like freeform 3D FPS. This objects connects to this and that and that and that, and I "see" how they interact around it.

        I'm quite aware I got a fairly big "cache" to map out such problems in, I kinda doubt that works for everyone. I'm nothing like those people that manage to use long term memory to do insane math calculations, but well above average.

        I remember I got it "wrong" on a math estimation test (i.e. not supposed to do any math on paper, no calculator) because I was too accurate. They suspected I was cheating, until I told them to give me a few bonus questions orally.

        It's nice for doing wild tricks like:
        Q:"What is the cube root of 53,582,633?"
        1. last digit = 3, from 7^3 = 343 (1-to-1 mapping) -> ends in 7
        2. 3^3 = 27 begins with 3
        3. a) 33 - 7^3 = 33 - 43 = 90 mod 100,
        b) 3 * 7^2 * x = 9 mod 10
        3 * 9 * x = 9 mod 10
        7 * x = 9 mod 10
        x = 7 -> middle is 7
        A: "The answer is 377"

        If you have the squares (1,2,4,16,25,36,49,64,81) and cubes (1,8,27,64,125,216,343,512,729) memorized you can do this in real-time, or at least I can. Trust me, it'll completely freak your friends out.

      • Re:Looks like... (Score:3, Interesting)

        don't know about you, but when I program, I *do* think visually about it. It's really hard to describe exactly how, but to me, writing in a programming language "feels" more akin to drawing a picture than writing an essay.

        That's because you're nuts.

        When I program, it's more like playing guitar than anything else. Complete with movements, climaxes, anticlimaxes, cigarette breaks, and all. Sometimes I just play the blues (php). Other times I like to break into hardcore metal (c++). But once I get going

      • Re:Looks like... (Score:4, Interesting)

        by DarkSarin ( 651985 ) on Friday April 16, 2004 @08:03AM (#8879674) Homepage Journal
        First, intelligence is a *very* complicated beast. Second, we don't have as good of an understanding of it as we'd like (by we, I mean psychologists, who are the primary researchers in intelligence).

        Simply put, spatial reasoning isn't that strongly related to verbal reasoning, or mathematical reasoning. Creative ability also seems to be fairly independent of the above. Mechanical ability does seem to be related to creative ability.

        STWM is related to most of the above--it seems to be one of the most important sections of memory/intelligence (that's why this finding is so important).

        As some one who is very interested in intelligence testing, I would just like to say that from what I can remember, programming (in general), is most strongly correlated with mathematical ability, although some of the others that are mentioned above are important.

        However, its important to remember that some people who are very successful programmers don't seem to have the ability to "visualize" things at all. We frequently assume that most people can do the "cube test", (where you are asked to visualize a white cube painted red. Then slice it into smaller cubes. You are then asked to state how many cubes there are, how many white faces, how many red faces, things like that. Also, how many cubes have 2 red faces.) but there are a few people who are very mechanically inclined who simply can't do this visually.

        Like I said, intelligence is very complicated, and to see a lot of people here try to boil it down to a simple idea is somewhat painful (but even the pros like to do it, so what can I say).
    • Re:Looks like... (Score:5, Interesting)

      by cperciva ( 102828 ) on Friday April 16, 2004 @05:23AM (#8879217) Homepage
      And what about the famous "magic number", 7 +/- 2? These people seem to be offering 4 +1/-2.

      It was found that the famous "5-9 digits" resulted from a bogus test. Rather than testing short-term memory, it was testing the "auditory loop" -- people weren't remembering the digits, they were mentally replaying the sound of someone speaking the digits.

      When people are given the digits via non-auditory means, 3-5 digits seems to be the norm.
  • by Genoxide ( 633645 ) on Friday April 16, 2004 @04:51AM (#8879086)
    Hmm.. Makes you wonder if it's possible to overclock your own brain. Some kind of implant with electric stimuli.. Or maybe some kind of chemical. Only, I can't quite figure out how to make a decent cooling solution, and I absolutely refuse to walk around with a heatsink attached to my forehead! ..Or if you find out how to stimulate that part, maybe some good oldfashioned brain exercise to increase your cache and speed. On second thought.. Nah.. Not really geeky enough ;)
    • Any true geek knows that you can overclock the brain with a little help from our friend caffeine.
    • by powerlinekid ( 442532 ) on Friday April 16, 2004 @04:57AM (#8879123)
      I know a guy named "Larry" who runs a business out of an alley selling products that do this. I'd give you his card, but hes really damn paranoid about cops.
    • by NoOneInParticular ( 221808 ) on Friday April 16, 2004 @05:08AM (#8879169)
      Overclocking my brain? For what purpose? I'm already capable of changing my mind 5 times a minute. More would not help.

      Hmmm, on second thought, scrap the above.

    • Our neurons fire at 200 Hz. So if there was really a way to overclock our brains to today's CPU clock frequencies, we'd all become hyperintelligent (and pandimensional :-) beings. But then again, brain cells are 10^7-10^8 times as energy efficient as silicon chips. Yup, 10-100 million. You can't have your cake and eat it too, I guess.
      • by Gyan ( 6853 )
        You meant that neuronal oscillation could go as fast as 200 Hz!

        Most of your neurons certainly don't fire at a mean rate of 200 Hz. In fact, when you're actively concentration, your EEG readings show brain waves at 30+ Hz. In fact, trains of 200 Hz firings are called 'fast ripples'. That itself gives you a clue that 200 is not the norm.
      • by DigiShaman ( 671371 ) on Friday April 16, 2004 @08:27AM (#8879788) Homepage
        By overclocking your neurons, you might be changing your perception of time relative to everything around you. So while you may think faster to everyone around you, you may not notice anything different in terms of perceived intelligence.

        Actually, time might slow down around you. Imagine being able to see a humming bird flap it's wings in very slow motion (assuming the human eye can refresh at a high enough rate) with ease. Also, imagine everyone talking in slow motion. Basically, time is in total slow motion relative to your speed of thought.

        Remember, your speed of thought doesn't = increase in complexity of intelligence.

  • by guttergod ( 94044 ) on Friday April 16, 2004 @04:51AM (#8879091)
    There has been plenty of studies showing that people tend to remember things incorrectly. Could this very short term memory be part of the final proof needed to invalidate witness statements in legal cases? Or perhaps they can use the line and dots test on witnesses and see how likely they are to remember something that happens in a glance. If they check high on the test, they might be more likely to be able to remember an incident correct.
  • Brain Cache (Score:2, Funny)

    by Anonymous Coward
    This post leaves very little to discuss.
    Which is why:

    Imagine, if you will, a Beowul....

  • The magical number 7 (Score:5, Informative)

    by foobsr ( 693224 ) on Friday April 16, 2004 @05:00AM (#8879136) Homepage Journal
    Most people can hold three or four things in their minds at once when given a quick glimpse of an image such as a collection of coloured dots, ...

    Did it not also depend on what kind of (was it) chunks you store (if this is at all what is stored in should it perhaps be ultra-) STM ?

    Where it "started": []

    The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information
    by George A. Miller
    originally published in The Psychological Review, 1956, vol. 63, pp. 81-97

  • If Brain has a cache somewhere, his less mentally endowed partner in crime should still get a cut.
  • I initially read this as "Brian's Cache Memory Found" and thought "hmmm, that's nice...good for him."
  • A coincidence (Score:4, Informative)

    by Gyan ( 6853 ) on Friday April 16, 2004 @05:06AM (#8879160)
    I'm reading Kandel & Squire's Memory [].
    Wonderful book.

    Anyway, this is just the "visuospatial sketchpad" as the authors call it. There's also the phonological loop dealing with meaningful sounds, among other types of working memory. So this isn't the be-all and end-all of even immediate memory.
  • by hak1du ( 761835 ) on Friday April 16, 2004 @05:07AM (#8879165) Journal
    Increasing your cache memory is clearly beneficial: it can only decrease access time to memory. Increasing STM, however, isn't necessarily good: if you remember more things simultaneously, your brain likely has to make associations between more things at a time. Whether it can or cannot depends on other parts of the brain.

    In fact, it seems likely that cause and effect are reversed: it seems likely that "higher intelligence" probably causes a larger STM rather than the other way around--the size of the STM would adapt to the needs of the rest of the brain rather than the other way around.

  • Brain Cache (Score:5, Interesting)

    by nimblebrain ( 683478 ) on Friday April 16, 2004 @05:11AM (#8879175) Homepage Journal

    It's not too surprising that the brain's short-term visual cache would be closer to the visual cortex. What I would like to know is how closely the visual cache is related to intelligence. Does it need actual visual input, instead of just imagined, and if so... <facetious>do you become marginally dumber when you close your eyes?</facetious>

    From reading Synaptic Self, the "general" cache and CPU area would seem to be the prefrontal cortex. It can activate memories to work on (the closer the current emotional state it was recorded in, the better), and hold a few things to work on. Perhaps there are many more specializations yet to be uncovered, but I'm struck at the sheer relative size of brain required to actively think and plan a next move. Considering that even a worm brain can get its owner around, you'd think our capacity for juggling thoughts would be encyclopaedic.

    I'd be curious as to what connections this area has to the prefrontal cortex - I've heard of the spots tests before - I don't recall it being related to general intelligence.

    Addressing the question of how cache gets spat out to hard drive, as it were, to keep thoughts in slightly longer-term storage, it looks like thoughts have to be put through the hippocampus and entorhinal cortex, where they will slowly get rewired (indexed?) over the course of about two weeks - about the length of memories you can lose under strong electroshock therapy.

    So many small functional pieces of the brain; I'm struck by how independent the sections of the brain are, by and large. Large-scale coordination has to go through a secondary 'chemical drip' system, from neuromodulators released by non-connecting nerves throughout the brain. It's that level of coordination required to put your brain to sleep or wake it up, amongst other things.

    I'm looking forward to more decoding of the brain's structures - narrowing down specific activities to a small area of the brain like they did is fantastic.

    • Re:Brain Cache (Score:3, Informative)

      by olethrosdc ( 584207 )
      Recent publications (I think in Science) blur significantly the distinction between actual and imagined visual input. I don't remember the names of the areas involved, but the results indicated that the part of the visual cortex that was initially thought to be only activated by the retina, showed visual like activity when subjects where dreaming.
    • Re:Brain Cache (Score:5, Interesting)

      by umofomia ( 639418 ) on Friday April 16, 2004 @06:16AM (#8879366) Journal
      It's not too surprising that the brain's short-term visual cache would be closer to the visual cortex. What I would like to know is how closely the visual cache is related to intelligence. Does it need actual visual input, instead of just imagined...?
      Well, in the case of blind people, the visual system of their brain is taken over by their auditory system. They end up processing sound they way sight is usually processed, allowing them to "see" with whatever limited audio cues are given to them. It's amazing how adaptive the brain is.
      • Well, in the case of blind people, the visual system of their brain is taken over by their auditory system. They end up processing sound they way sight is usually processed, allowing them to "see" with whatever limited audio cues are given to them. It's amazing how adaptive the brain is.

        Not completely surprising - since the human brain also does some echolocation (and other processing of sound redundancies and missing energy in particular bands into information about nearby objects).

        Both systems involve
  • STWM Damage (Score:2, Interesting)

    by arestivo ( 459117 )
    What would be interesting to know is if the brain is able to shift this function to other parts of the brain in case of some kind of brain damage, and what are the consequences of the damage if it is unable to do that.
  • by Zog The Undeniable ( 632031 ) on Friday April 16, 2004 @05:46AM (#8879295)
    Because I often go upstairs and can't remember what I went there for.
  • by jcdr ( 178250 ) on Friday April 16, 2004 @07:30AM (#8879562)
    From the article I found very weak the conclusion that this brain section act like a cache. This can be a multiplexer that connect a processing section the the memory section. Or more simply registers that hold intermediate informations.

    All the 3 systems have in common that there are build with memory cells, but there are different in terms of the way the memory are used and the associativity. Registers and caches hold encoded informations; multiplexer don't care of the encoding. registers don't have any associativity between a tag and tne information stored, only cache have that.

    All tree systems generate heat and consum power that the brain camera see. Really, I see nothing that assert this is a cache.

    Sound like the author want to use high-tech buzz word, without any prof.
  • Misleading Article (Score:5, Interesting)

    by edibleplastic ( 98111 ) on Friday April 16, 2004 @08:07AM (#8879696)
    Both the Nature article and the posting here on /. are exceedingly misleading (I don't blame the poster... he/she just reported what the Nature article said)

    All that the two articles *may* have found is the location of a part of VISUAL working memory. This would be the area that tracks objects through space and binds features that are processed seperately by the visual system (say color and form) into the same object. This is NOT the seat of all intelligence.

    There are many different aspects to working memory: people have hypothesized that there is a phonological working memory, one involved in the spelling process, one involved in computing things like syntactic relations, etc. And yes, there is probably such a thing as a general-purpose working memory. All they may have found is the location of the visual-spatial component of working memory. This is a far cry from finding anything that limits one's intelligence, unless you define intelligence as "visual-spatial ability".

    In fact, it is quite wrong to even suggest that the visual-spatial working memory is somehow related to intelligence. There are many instances of people with working memory deficits who are able to function quite normally in other domains.

    For the sake of brevity I won't go into the finer about the studies themselves (one of the studies used the ERP recording technique, which is *awful* at localization) because the main point is that in and of themselves the studies are fine. It's this conclusion that they've somehow found "the RAM" or the thing that would limit intelligence that's exceedingly problematic.
    • by iabervon ( 1971 )
      To use the computer analogy, it's like they took a computer and tried looking for where the cache is. After performing a bunch of graphics tests, they found that the cache is on the graphics card.

      I suppose there is one thing here that people are not generally aware of: working memory (and long-term memory) is not distributed evenly throughout the brain, but is, rather, in the areas where the things you're remembering are processed.
  • by adamofgreyskull ( 640712 ) on Friday April 16, 2004 @08:11AM (#8879710)
    I haven't seen anyone bring this up, on this story or otherwise...but I read in New Scientist last year about functional MRI being the phrenology of our time. I can't find reference to it on the website, but a google returns this [] among others [].

    Could anyone here shed any light on this?
  • Planned Motor Memory (Score:5, Interesting)

    by FrenZon ( 65408 ) * on Friday April 16, 2004 @08:21AM (#8879764) Homepage
    Often I find myself going to type in the URL of a website, manage to get distracted by four things on the way to focusing on the location dialogue, and by the time I'm read to type, I've completely forgotten where I was going to go.

    However, if at that point I just 'let my fingers go', they can usually type out the first 5 letters of whatever it was I was going to go to, even if they weren't in typing position.

    This is extremely handy. Any idea what it's called?
    • I do that too! (Score:4, Interesting)

      by phreakmonkey ( 548714 ) on Friday April 16, 2004 @06:54PM (#8887397) Homepage
      It's creepy when I manage to enter an entire URL or complete a sequence of actions without remembering why...

      It usually goes something like this:

      1. I think "oooh, I need to recompile that kernel module on host foo."

      2. I turn on the computer monitor to find Slashdot or something else distracting already up on the screen.

      3. I start a MP3 stream, read a couple of articles... get generally distracted.

      4. I think "What was I going to do?". I then just relax and let myself do whatever comes naturally, and which point I launch my SSH client, log into the host and get about half way to the task when I remember where I was going with it and "consciously" continue from where I managed to get myself without thinking about it.

      I know, that sounds a bit odd.. but I'm serious- that's how it happens! And it happens more and more as I get older. (I'm almost 30.)

      I attribute it to "muscle memory"... It feels exactly the same as being able to play the first part of a song on piano or guitar before remembering what it is I'm playing, which I'm sure any musician can relate to.

      I figure I started planning the familiar sequence of computer events in my head back when I thought "I need to...", so I'm able to just plow through that sequence naturally and observe it to get clues where it was I was going with that action. God that still sounds odd, but that's exactly how it happens.

      Of course, I drive my car in the same fasion... once again more and more as I get older, and it drives my girlfriend CRAZY.

      "WHERE are you going? Why do you always turn that way regardless of where we are trying to get to?!?!?!"

      "Ooops... sorry... everywhere else I drive starts with that sequence of turns."


  • by bmf033069 ( 149738 ) on Friday April 16, 2004 @09:42AM (#8880254)
    I find the methodology of their research much more interesting than their results. I've done quite a bit of work in this area, including my dissertation, and from the very high level description of the tasks involved their results need to be interpreted in a much more limited sense than they are being presented.

    The task that you are given for a specified stimulus is going to very much influence your performance on later tasks. If you are presented a slide and asked to count the number of dots, then later asked whether or not the number of dots on a particular slide was even / odd, then you are likely to do fairly well. But what if you are presented a slide and asked if there was a blue dot on the slide or not, how is your performance going to be on the even / odd task later on? What kind of curve are you going to get for each task when you vary the number of dots and can you really then imply a limit to the theory of memory?

    Obviously, you need more details than is presented in the shorter article. The last paragraph below is particularly interesting, since such generalizations don't seem to follow very well from the methods described.

    I also would wish people would stop making analogies between the mind and the computer. It is a useful analogy for teaching undergrads and for articles in pop psych magazines, but is very restricting in terms of actual research directions.

    Included below is additional text related to the story:

    "Visual short-term memory is a key component of many perceptual and cognitive functions and is supported by a broad neural network, but it has a very limited storage capacity," Marois said. "Though we have the impression we are taking in a great deal of information from a visual scene, we are actually very poor at describing its contents in detail once it is gone from our sight."

    Previous findings have determined that an extensive network of brain regions supports visual short-term memory. In their study, Todd and Marois showed that the severely limited storage capacity of visual short-term memory is primarily associated with just one of these regions, the posterior parietal cortex.

    Todd and Marois used functional magnetic resonance imaging (fMRI), a technique that reveals the brain regions active in a given mental task by registering changes in blood flow and oxygenation in these regions, to identify where the capacity limit of visual short-term memory occurs.

    The brains of research participants were scanned with fMRI while they were shown scenes containing one to eight colored objects. After a delay of just over a second, the subjects were queried about the scene they had just viewed.

    While the subjects were good at remembering all of the objects in scenes containing four or fewer objects, they frequently made mistakes describing displays containing a larger number of objects, indicating that the storage capacity of visual short-term memory is about four.
  • by cybercreek ( 568255 ) <mkelsey@ea[ ] ['rth' in gap]> on Friday April 16, 2004 @09:45AM (#8880284)
    Be a real man! Increase your cache memory by 300.5GigaCells. Order today!

    Your girlfriend will say, "Are you hot? Or is that a gun in your brain?"
  • by BobRooney ( 602821 ) on Friday April 16, 2004 @11:05AM (#8881099) Homepage
    The article, and the researchers in the article are making an assumption about intelligence: they're assuming raw information processing power IS intelligence. I would argue that a more substantial defining factor is recall of previously processed information and the clarity of that recall. In school, the Cram -->Take Test --> Brain Dump method works but doesn't foster leaning in the way that creates "intelligence" by my definition. If everyone were to re-take their final exams from their senior year of high school/college TODAY I would argue that those doing the best overall were the most intelligent, particularly if their school-age years were long ago.
  • by RhettLivingston ( 544140 ) on Friday April 16, 2004 @11:14AM (#8881186) Journal

    than the others I've seen here is that, since it is localized instead of distributed, getting to the point of injecting signals into this cache and thus effecting one's view of immediate reality may be much easier than thought before. Say, 30-40 years away instead of over 100.

    Actually though, I'm not sure why they would have thought this was spread about. Neural pathways are very slow in general. It seems like localization of highly related data such as the components of an image would be necessary due to that fact alone.

  • by spectecjr ( 31235 ) on Friday April 16, 2004 @12:41PM (#8882274) Homepage
    Surely the V5 area of the visual cortex is the actual cached short-term memory store?

    The entire area is a nest of feedback loops - with the visual information looping round in that area through several layers of neurons both above and below.

    It could be that there are two caches: the visual cache is in the V5 layer, and the semantic cache is this one that they've found with the MRI.
  • Einsteins (Score:3, Interesting)

    by butane_bob2003 ( 632007 ) on Friday April 16, 2004 @02:27PM (#8884052) Homepage
    This would fall in line with the fact that very smart people like Einstein, Feynman, and the like are/were able to visualize complex systems and ideas easily. 'Visual thinking' comes naturally to them. I'm not sure why this doesn't always translate into high mathematical talent. I've noticed that some very smart people are not able to calculate quickly or perform large calcuations without the help of paper or a computer They are able to plan out and model complex software systems in their heads, or design and understand complex mechanical systems and engineering problems easily. It seems like some people fall into the 'good at numbers' camp and others are in the 'good at language' camp. Not sure if this is related to their 'cache' size.
  • Corrections (Score:3, Interesting)

    by DynaSoar ( 714234 ) * on Friday April 16, 2004 @05:15PM (#8886353) Journal
    They did not map STWM, they mapped ONE visual-only application of one part of STWM, the visuo-spatial "scratchpad". They did not test spatial relationships, so they did not test the entirety of V-S STWM. There is no reason to assume that had they tested spatial memory, the result would have been in the same place. For that matter there's no reason to assume that if the stimuli were words instead of dots the result would be the same.

    They also did not test the auditory portion of STWM, the "phonological loop". Nor did they test the functional control mechanism that operates these, the "central executive".

    One particular application of STWM might appear this localized. There's no reason to expect a different application to be in the same place. In fact, it'd be ridiculous to expect it. It's far more likely that, given all the possible localizations that could be found for the various tasks STWM can tackle, the outcome would be exactly the opposite of what's stated: STWM *is* distributed around the cortex.
  • by mr. squishie ( 726877 ) on Friday April 16, 2004 @05:47PM (#8886696)
    Let me say first that though I'm not an expert, I am studying for a degree in psychology and neuroscience with a specific emphasis on connectionist modelling of the brain, so this research is very relevant to what I have some experience/interest in...

    Anyways, before everyone gets excited about the brain's "cache", it's important to remember that computer processors and neural networks like our brain process information in entirely different ways. You get similar results some of the time, but for different reasons. The key difference is that our brain processes information in parallel, on a massive scale.

    People talk about the computer-brain analogy being useful on a general level, but it's actually entirely wrong on any level. When it comes to memory, this is especially important. Our brains work by sloshing around activity through enormous numbers of neurons across interconnected layers; basically, this leads to two types of memory: active memory (patterns of activity that are actively maintained across time) and weight-based memory (adjusting the connections between neurons to influence the future processing of activity.) Usually such "short term" memory as that is being discussed in the article is referring to active memory.

    Anyhow, the important bit to take away from all of this is that active memory in the brain is something that requires a lot of upkeep. It's not like computer memory that holds specific information that can be erased or retrieved--rather, it biases current processing based on a pattern of activity that resulted from past processing. Without going into too much detail, in the case of remembering dots positioned on a screen, you can imagine that seeing the dots spreads activity through the cortex, including both the spatial processing areas and some "active maintainer" area that is able to lock in patterns of activity. In the context of the test, the representation of the dots in the spatial layer activates another pattern of activity in the "active maintainer," which sort of "locks on" to the activity in the maintainer that corresponds to the the represenation of the dots in the spatial layer. When recall time comes, the active maintainer sends activation to the dots representation in the spatial layer--you can then visualize what you just saw a moment ago (literally activating the same neurons). This depends on the quality of the represenation in the active maintainer, of course, and is really oversimplified, but you can sort of get an idea of the complexity involved.

    Anyways, there's already a lot of evidence that the prefrontal cortex is heavily involved in actively maintaining a set pattern of activity in the face of distraction, but since prettymuch all distinctions in the brain are gradual and not absolute anyways, it wouldn't be too surprising to find that another part of cortex could be more specifically involved in maintaing representations in the spatial processing part of the brain.

    As for cognition and intelligence, there's no question that active memory is important for intelligence--if you don't have it (if you are lobotomized, removing the entire prefrontal cortex), you can't direct your thoughts to reflect anything that came before, and you become a vegetable. But as to the contribution of this specific brain area, that's clearly going to be speculation at this point.

It's fabulous! We haven't seen anything like it in the last half an hour! -- Macy's