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Memory Molecule Identified

Reader Ostracus informs us of research led by Michael Ehlers of Duke University that has identified a molecule, myosin Vb (five-b), that seems to be a critical component in the formation of memory. "A major puzzle for neurobiologists is how the brain can modify one... synapse at a time in a brain cell and not affect the thousands of other connections nearby. Plasticity, the ability of the brain to precisely rearrange the connections between its nerve cells, is the framework for learning and forming memories ... The discovery of a molecule that moves new receptors to the synapse so that the neuron... can respond more strongly helps to explain several observations about [brain] plasticity ... [The researchers] found that the myosin Vb molecule in hippocampal neurons responded to a flow of calcium ions from the synaptic space by popping up and into action. One end of the myosin is attached to meshlike actin filaments so it can 'walk' to the end of the nerve cells where receptors are. On its other end, it tows an endosome, a packet that contains new receptors. 'These endosomes are like little memories waiting to happen,' Ehlers said."

25 of 97 comments (clear)

  1. Problems with the headline by philspear · · Score: 5, Informative

    I'm not sure they can call this a "memory molecule" so much as a "molecule responsible for changing the receptors at the synapse to make a memory." The molecule itself is not what memories are actually made of, which is what I would think of. The changed activity of the neuron is more akin to that. And it's also not specific to memories. The process of myosin Vb bringing endosomes to the surface is not unique to neurons, that's been known for a while (http://www.ncbi.nlm.nih.gov/pubmed/11408590).

    That said, it's really interesting that they've identified this, as it not only tells you how the change is made, but also tells you the stimulus to change it.

    1. Re:Problems with the headline by Compuser · · Score: 5, Insightful

      Myosin V is a major motor which hauls all kinds of stuff. Calling it a memory molecule is like calling a Volvo truck the food truck. Yes, it might be used to deliver food sometimes but it is much more than that.

    2. Re:Problems with the headline by alexj33 · · Score: 2, Funny

      So this means the new Samsung brain-dump backup drives will be on the market by the end of the year.

  2. Re:Sound rough by Anonymous Coward · · Score: 2, Funny

    And my take is that I'm going to start mixing energy shakes with myosin Vb (from ground up uncooked cattle brains). Photographic memory here I come! Yeehaw!

  3. The further this research goes... by symbolset · · Score: 4, Funny

    The closer we are to immortal memory. That would be both good and bad. We would forever despair of our failures. We would always remember where we left our keys.

    Since all the other parts of a Man are capable of being restored through regressing any cell into a T-cell and then culturing it into the desired part, if this gets us to where we can keep the mind functional as well, then we've found Ponce deLeon's fountain of youth.

    That would be great, because there are only 6 billion of us, and that number was not growing nearly fast enough.

    --
    Help stamp out iliturcy.
    1. Re:The further this research goes... by Anonymous Coward · · Score: 3, Funny

      That would be great, because there are only 6 billion of us, and that number was not growing nearly fast enough.

      Improved memory might actually slow that down. If certain memories weren't overriden by hormones etc, then memories of three A.M. feedings, diaper changes, child support etc might dissuade us from sex without birth control methods. Then there is the possibility of your partner never forgeting your "mistakes",,,,

    2. Re:The further this research goes... by Singularitarian2048 · · Score: 2

      One of the most tragic parts of being human is that we forget the details of the romances of our youth.

    3. Re:The further this research goes... by Creepy+Crawler · · Score: 3, Funny

      No. By far, the most tragic happening of a human is that we die.

      20, 50, 100 years of happenings, memories.. All erased, with none ever being recoverable.

      That is a horrible thing that needs to be stopped at all costs, unless the person willfully chooses to do so. That being said, I am a Singultarian.

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    4. Re:The further this research goes... by Thiez · · Score: 3, Insightful

      > 20, 50, 100 years of happenings, memories.. All erased, with none ever being recoverable.

      Let's be honest, there are a lot of memories that are not important to anyone but the one who remembers them. When I die nobody will know which pair of socks I liked best, but the loss of this knowledge is hardly a loss for the human race. Even if I were write down the things about my life that I consider to be the most important in an autobiography, how many people would read it? Humanity is not interested in the thoughts and memories of random people.

      Write down the few happenings and memories that were relevant for (a large part of) the human race. The rest can be forgotten.

      > That is a horrible thing that needs to be stopped at all costs, unless the person willfully chooses to do so.

      I don't like people who are willing to accomplish some goal 'at all costs'.

    5. Re:The further this research goes... by Dusthead+Jr. · · Score: 2, Interesting

      How do you explain YouTube? Humanity might not be interested in the thoughts of random people, but other randome people are.

  4. Re:Sound rough by MillionthMonkey · · Score: 5, Funny

    I'm taking actin and will soon kick your ass. I will crush you with my contractile system and force feed you ATP with my sliding filaments as I hurl you in toward my M line.

  5. Re:Sound rough by MrMr · · Score: 2, Insightful

    Perhaps it is a piece of research that will not result in a product that somebody can sell at a huge profit, but will only increase our understanding of the world a little.
    Or is that too silly to consider?

  6. Random musings about calcium by jonaskoelker · · Score: 4, Funny

    myosin Vb molecule in hippocampal neurons responded to a flow of calcium ions

    "So remember to drink your milk, boys and girls, or you will forget how to."

    1. Re:Random musings about calcium by ozbird · · Score: 2, Funny

      myosin Vb molecule in hippocampal neurons responded to a flow of calcium ions

      "So remember to drink your milk, boys and girls, or you will forget how to."

      Forget milk; drink Vb and alter your synapses directly.

  7. Applications and deeper questions by jonaskoelker · · Score: 2, Interesting

    On a more serious note...

    "We all know"---I really ought to find an article that backs me up on this, but I've heard it enough times from random sources so it must be true---we all know that breast milk is very good for babies.

    I'm wondering whether there's a large amount of calcium in breast milk, and whether that influences the babies' ability to form memories. The summary doesn't say whether the calcium acts as a "mere" catalyst or is used up in the process; but in any case, I'd guess that more is good.

    [I also really should check whether calcium crosses the blood-brain barrier]

    We can also contemplate applications. Is "forward amnesia"* caused by calcium not being where it needs to be in large enough amounts? Can we wrap calcium in a road map that guides it there and cures the amnesia?

    * forward amnesia: the kind where you remember everything up to the point where you got it, but don't form new memories after that very well or at all. As opposed to retrograde amnesia, where you remember well after the point where you got it, but poorly or not at all what happened before it.

    Google can probably give me answers, but I can't remember how to use it. I haven't had my milk today :)

    1. Re:Applications and deeper questions by Anonymous Coward · · Score: 2, Informative

      The summary doesn't say whether the calcium acts as a "mere" catalyst or is used up in the process; but in any case, I'd guess that more is good.

      The calcium (Ca2+) signal is just due to a very temporary Ca2+ influx into the cell. The Ca2+ stems from the extracellular fluid and from intracellular Ca2+ stores. After excitation, Ca2+ gets immediately pumped out of the cytosol. None gets used up. (This is only half the truth: Some Ca2+ signals are lasting for minutes to hours.)

      [I also really should check whether calcium crosses the blood-brain barrier]

      It does. Calcium signaling is essential not only for muscle action, but also for nerve cell signaling (and many other cell types use Ca2+ signaling, too).

      We can also contemplate applications. Is "forward amnesia"* caused by calcium not being where it needs to be in large enough amounts?

      Anterograde amnesia is usually induced by drugs (AFAIK the mechanism how that works is completely unknown) or by traumatic brain injury to regions responsible for memory formation, i. e., damage to the medial temporal lobe and especially the hippocampus. Concerning the drugs (benzodiazepines), they target GABAA receptors, thereby inhibiting neuronal signaling. That is, they have indeed some influence on Ca2+ signaling, too, but they also influence action potentials induced by Na+/K+ signaling ... saying anterograde amnesia is caused by lack of Ca2+ is a little far stretched.

      Google can probably give me answers, but I can't remember how to use it. I haven't had my milk today :)

      The main reason you should specifically care about your diet containing enough Ca2+ is that Na+ and Cl- and most other minerals are abundant (concerning Na+: far too abundant) in almost any food we eat. Therefore, you will almost never suffer from lack of Na+, but lack of the more rare Ca2+. (Lack of Na+ would be very detrimental to neuronal action and to your health, too: In a desert you lose very much NaCl and therefore you have to uptake large amounts of salt--and of course even more water ...)

  8. Deja Vu by CarpetShark · · Score: 4, Funny

    It might be the beginning of a breakthrough, but that remains to be seen. My take is: wait and see.

    That's what everyone said last time we discovered this, back in 1925, 1903, and 1871. Somehow, after discovering these molecules, everyone forgets to follow up.

  9. Re:Sound rough by Thiez · · Score: 2, Informative

    Wikipedia is your friend :)

    It appears actin is part of filaments which are a rather important part of the contractile system, which is the system that gets your muscle cells to contract (which makes you muscles move). I have not a clue what an M line is. ATP is an important chemical that your cells internally use for energy. Why one would force feed someone ATP is beyond me (AFAIK it does not do anything special when ingested).

    It appears MillionthMonkey is boosting his strength while Anonymous Coward is boosting his memory -> MM kicks AC's ass. (or something like that)

    I used to be good at biology :(

  10. It's not tragic at all? by tjstork · · Score: 5, Insightful

    Death is a part of the natural renewal of things. It is a short life span and the continual and restarting of youth that allows humanity to not only change its education but its social attitudes.

    Mourn the ones we lose, for sure, but ultimately, death is necessary. Without death, young people could never remake the world with each generation, and we'd be stuck forever with the weirdness of the old. Sometimes we old people, instead of clinging to life, just need accept that we're going to die.

    --
    This is my sig.
    1. Re:It's not tragic at all? by Roxton · · Score: 2, Interesting

      As we get older, couldn't we just adopt a social system that makes us older instead of, you know, dying? Killing off the elderly is a pretty ham-handed solution.

      Unless you're just trying to rationalize the inevitable, in which case your sentiment is total garbage.

    2. Re:It's not tragic at all? by Roxton · · Score: 2, Insightful

      If that's your concern, couldn't we just adopt a social system where we get less relevant as we age? Killing off the elderly is a pretty fucking ham-handed solution.

      Unless you're just trying to rationalize the inevitable, in which case your sentiment is total garbage.

    3. Re:It's not tragic at all? by Gavagai80 · · Score: 2, Interesting

      His point is that if old people didn't die, McCain would win the election due to his demographic strength with them.

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  11. Re:Sound rough by dimeglio · · Score: 5, Interesting

    I see here a possible method of improving AI. If we can indeed model synthetic neurons to perform in a similar way, we might have the key to designing more efficient captcha breaking systems.

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    Views expressed do not necessarily reflect those of the author.
  12. The human brain is full of VB? by Ant+P. · · Score: 5, Funny

    At least now we know why it's so unstable

  13. Re:Sound rough by mysticgoat · · Score: 3, Interesting

    Google on "artificial neural network" and read a few of the 600,000 hits that you will find. ANN theory is as old as digital computers. Commercial ANN applications have been growing in number and sophistication for over 10 years, e.g,, Dragon NaturallySpeaking and other speech recognition software, Caere OmniPage and other OCR packages.

    What TFA is about is reporting the discovery of a key part of the mechanism that changes the weighting factors in a neuron in a biological neural net. Of itself, I doubt that this will trigger any insights on how to improve ANNs: the frankenmeisters already know how to do that with the neurones they work with. But this does open the door for further research by biologists into wetware neural net mechanisms, and that could lead to some interesting things.