Tuesday, December 7, 2010

The Brain's Memory "Buffer"

It's ironic but appropriate that I don't remember how I happened upon this  article on scientific research into the cellular differences between short term and long term memory storage. The newspaper is called The Hindu, and so it's not one that I come across in my normal web wandering.

It's probably more informative to read the article, but just to move this info from my short term memory to something a little longer, I'll summarize by saying that scientists have found evidence that short term memory is held in single nerve cells in the front of the brain, for a minute or longer. "Permanent" memory (to me a dubious concept) is formed when the amino acid glutamate stimulates nerve cells in the brain to reorganize and strenghten their connections with each other. But this process takes time and is to slow to deal with rapidly incoming information--as what isn't these days?

Enter metabotropic glutamate transmission. A rapid fire signal stimulates single cells to be temporary storage for moment to moment information. The example the article uses is that of a card shark counting cards in a game of blackjack. This would seem an oddly random example, except it goes on to say that casinos have figured out that it the type of memory that is most sensitive to disruption by alcohol and noisy distraction.

"It's more like RAM [random access memory] on a computer than memory stored on a disk," Dr. (Don) Cooper said. "The memory on the disk is more permanent and you can go back and access the same information repeatedly. RAM memory is rewritable temporary storage that allows multitasking." 

The researchers also did experiments on mice to see how these findings work with addiction. Apparently, a neurochemical called dopamine is what helps focus attention and make fast decisions, but after mice were given repeated doses of cocaine to simulate addiction, the  short term memeory "buffer" cells were no longer
as easily stimulated. Even adding dopamine after did not have the effect of focussing the mice's thought processes.

"If we can identify and manipulate the molecular components of memory, we can develop drugs that boost the ability to maintain this memory trace to hopefully allow a person to complete tasks without being distracted," Dr. Cooper said. "For the person addicted to drugs, we could strengthen this part of the brain involved with decision-making, allowing them to ignore impulses and weigh negative consequences of their behavior before they abuse drugs."

Maybe, maybe not. As usual with these things, though, I mainly feel sorry for the mice.


  1. I wonder if we sense any difference between the two types of memory, other than their duration.
    Detectives Beyond Borders
    "Because Murder Is More Fun Away From Home"

  2. Hard to say, in that, I at least, tend to think of it as I remember/I don't remember.

    Mostly, I don't remember. As in "sure I just waited on you two minutes ago, but I don't remember what the hell we were talking about"

    Maybe I should cut down on the cocaine.

    (Just kidding, federal drug monitors.)

  3. Hmm, it's fascinating to think of the role memory might play in the ability to concentrate. What role does memory play, for example, in our ability to assimilate syntax or to write a sentence or even a word? To write a word, for instance, one must preumably remember the previous letter. Or do our brains formulate all parts of certain tasks as a unit, rather than as individual parts?

  4. I don't know the answer to that, but it would be interesting to know.

    Makes me think about those studies that have been done that show that we don't really need much but the beginning and end of a word, at least a short one, to "read" it. And then, of course, there is Hebrew as an illustration, I guess.

  5. We "hear" and "see" based on what we expect. That's one reason reading or hearing a foreign language one knows but not well is so exhausting. One must pay close attention to every letter, every word.

    I suppose Hebrew, most often printed without vowel markings, is a good example. Context takes on such great importance. (The Bible is always printed with the markings, by the way, so it's a good place for beginners.)

  6. Hmm, I would not have thought the Bible would be a good place to start, simply because it is so freighted.

    It would be nice to study Hebrew, but since I haven't really gained fluency even in Spanish, which should be my second tongue by now, I'm not sure that it would be of a great deal of use.

    I'm not sure if I should even mention the semi (because misspelled) word that the word verifier came up with: pogreme

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  8. The v-word for my previous comment was even better, but I, er, can't remember what it was (Hmm, but that's interesting, isn't it, that one may remember the sensation created by some piece of information without, however, remembering the information itself.) I think the word was something like disablty -- at any rate, a misspelling of disability seemed appropriate for a post about memory lapses.

    Freighted or not, the Bible in Hebrew is always printed with the vowel marks, so it's easier for a beginner to read.

    One notable feature of Hebrew is its concision, due to combining forms. Thus

    "In the beginning God created the heaven and the earth" (10 words)

    is in Hebrew seven words:

    בְּרֵאשִׁית, בָּרָא אֱלֹהִים, אֵת הַשָּׁמַיִם, וְאֵת הָאָרֶץ.

  9. It won't show up here now, but 'somethking' was good.

    I have to say that the scripts of other languages are fascinating me. I don't know if it's lack of time, effort or will power that keeps me from pursuing them. I did at least learn the Greek alphabet, which surprisingly, I've retained.

    I mean, I have to work up to it, but it's still there. Somewhere.

  10. I was fascinated by the chart of alphabets in an old dictionary we had in the house when I was little.

    Your v-word may by vosy or even vosier, but mine is: vosiest.