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Brain's Cache Memory Found
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."
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.
A Fatal OE Exception has occurred, Sig will now reboot.
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?
W
-------------------
This is my SIG. There are many like it, but this one is mine.
good news for pr0n hounds.
too bad it's addicting
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...
Perhaps this explains why my head gets extremely hot when I do my Calculus exams.
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.
Sheesh, evil *and* a jerk. -- Jade
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 ;)
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.
Apple built a platform for their ideas, Google built one for everyone's.
I wonder what would happen if they just injected some stem cells around there?
(\_/)
(O.o) This is Bunny. (> <)
Thanks.
... not remember 4 spots of light.
... but I've also seen many of those same types fail when tasked with the above sorts of questions.
This seems to be quite questionable as far as any sorts of broad conclusions are concerned.
When people talk about "intelligence" they usually mean something like "being able to grasp two deep concepts and put them together"
Granted, I have seen a correlation between people who are capable of remembering 10 digit codes and intelligence
Maybe this is a red herring.
As my father lik@(munch munch)...
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
CC.
TaijiQuan (Huang, 5 loosenings)
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.
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.
Binary geeks can count to 1,023 on their fingers
When people talk about "intelligence" they usually mean something like "being able to grasp two deep concepts and put them together" ... not remember 4 spots of light.
... but I've also seen many of those same types fail when tasked with the above sorts of questions.
Indeed. Intelligent people would be those who are excellent at conceptual blending. List of resources on this page.
Granted, I have seen a correlation between people who are capable of remembering 10 digit codes and intelligence
I'm currently reading Kandel & Squire's Memory.
Having a too-good memory is what you don't want. They relate the case of a hyperretentive memorist from Russia, who had almost supernatural retention skills, but was hopeless at appreciating metaphors, or pattern matching or generalizations. Which are the building blocks of analytical intelligence.
Well, there's the obvious. Use it. A lot. The human machine is built around building up what gets "stressed." That goes for the brain too. For short term working memory exercise make references. Read a book, history or something like that, where you're bit over your head. Keep Google going while you do it and every time you hit something you don't understand do a search, follow the search to whatever else interesting it might lead to, bounce back and forth from the book to search materials.
/. on the side.
Now do it with two books, maybe even on different but related subjects, while you keep an eye on
This is pure "cache" work. Don't try to memorize any of it. That's a different "brain muscle." Isolate what you're exercising. You're just trying to keep the different threads of thought all going without losing them.
Now, remember what I said about getting stressed? Don't. Really, the biggest killer of working short term memory is any sort of tension. Tension is an attention grabber, and you only have a limited amount of attention at any one time. Learn to relax. Let it flow of its own accord. If you pick it it will never heal.
It's one of those zen things, where you hit the target by not being aware that the target is even there. The arrow releases itself.
Oh, and here's the nasty part. Just like stressing muscles to build strength, it's a use it or lose it deal. Yes, you can improve your short term working memory, but when you stop using it, the improvment will fade.
I really hate that part.
KFG
Setting aside the fact that drawing analogies between digital hardware and human wetware is somewhat dodgy... I'd have thought the equivalent of short term memory would run nearer 8GB than 8MB.
I don't know about you, but I'm a 'visual' thinker, and its all pretty much 3D images that come to mind. For example, reference to recent discussion invokes images of the actual conversation, not just the content. OK, human memory is pretty good at eliding details and interpolating from previous experience (analagous to heavy JPEG compression maybe?), but even 10minutes of pottering about the house must equate to a huge 'dataset'.
May be... But still I'm afraid that the size of your STWM is not going to impress your girlfriend.
- Back off man. I am a scientist
Because I often go upstairs and can't remember what I went there for.
When I am king, you will be first against the wall.
Well, one assumes a "hypertentive memorist" is dealing primarily with long-term memory. I interpret this article as dealing with the type of short term memory used in solving an equation, or writing a small code section. It's certainly possibly your HM was deficient in that area.
I think there's a valid point to be made about how much information someone can deal with in those contexts. The one caveat I'd make is whether the person is dealing with text or imagery - AFAIK there's quite a range there.
At any rate, I think it's clear that many intelligent people also have above average long-term memories.
Galileo: "The Earth revolves around the Sun!"
Score: -1 100% Flamebait
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.
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'.
That's nothing...
I can visualise the entire bits sequence of the resulting object whilst coding... I 'see' how the processor pointers will behave, even when programming in a high-level language like obfuscated Perl.
I can draw perfect circles by mentally calculating pi with a precision of 150 digits.
I can mentally render complex fractals, from the basic Mandelbrot set to a more complex Newton's Method in the Complex Plane.
And, yes, I can do crypto backwards. Triple-DES is very easy to do mentally. Doing it backwards is just a tiny bit harder.
-
Roses are #FF0000, Violets are #0000FF, find / -name '*base*' |xargs chown -R us && mv zig greatjustice
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!"
"No fair, you changed the outcome by measuring it!" - Professor Hubert J. Farnsworth
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.
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 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.
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?"
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.
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.
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.
Coming soon - pyrogyra
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.
Please keep in mind that your average Slashdotter couldn't bike more than a few miles without being close to a heart attack.
Nonesense, possibly on two scores. The first, reading other peoples's posts suggests to me that there are quite a number of Slashdotters who ride bikes and could keep up with me just fine.
But the second is the important one. If they can't bike more than a few miles without having a heart attack it's due to ignorance, not lack of fitness. I could teach nearly all of them how to do it within a week. An 11 year old girl, with no previous athtletic accomplishments, bicycled across America. It's really not that great a feat, if you still have the capacity to make it to the fridge for that last slice of last night's pizza you can bicycle a few miles just fine, but as in all things you have to properly understand what you are doing. Being able to balance a bicycle is not the same as knowing how to ride one properly.
It's true about the computer nerd thingy though, and I'm not a computer nerd, as I've written before. I'm an old style geek, which is rather a different beasty. Cycling, martial arts, squash, cross country skiing, mountaineering, all traditional pursuits of the traditional Anglo-American geek. The jocks went for football and rugby, the so called "contact" sports, whereas the geek was perhaps more inclined to make his contact with the point of an epee.
I really don't understand shunning exercise any more than I understand anti-intellectualism. Mind and body are inseperable. You can worry yourself sick, and exercise yourself unworried. And what are you doing to occupy your time while out on an eight hour bike ride?
You think a lot.
When properly done exercise is complimentary with thinking, nor does it take any time away from thinking. You don them both at the same time.
Gymnasium just means "Place to hang out, like, naked and shit." You might wrestle in the gym, or you might just argue natural philosophy for hours. . . and then settle the issue with three falls or a submission.
As per your last sentence, which is apropos to the other poster's comments, athletic accomplishment is a relative feat, not an absolute one. See the guys at the back of the marathon field? The one's who take six hours to finish instead of two and change? They're slower than the winner, but they're working just as hard as the winner did, for that entire six hours.
Some of the guys who win couldn't do that without having a heart attack.
Hawking is a great athlete, it's just that his athletic skills and accomplishments aren't readily visible to those without the right means of percieving them.
KFG
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.
"Ooops... sorry... everywhere else I drive starts with that sequence of turns."
{sigh}