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Thread: Nerves - electric, or sonic?

  1. #1 Nerves - electric, or sonic? 
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    There seems to be a new emerging theory about the way information is transmitted in the human nervous system. I'm not sure I fully understand the theory, but it seems to predict that information is carried using soliton sound waves that travel down the nerve instead of electric pulses.

    They make some compelling arguments in these articles, like pointing out that olive oil is very similar to the chemicals believed to be carrying the sound wave, and most anesthetics have in common the trait of being soluble in olive oil. (Raising or lowering the boiling point of a substance, by dissolving something in it, would affect how sound travels through it. )

    On the other hand, the existing electrical theory is supported by the fact the nerves are clearly observed to give off electrical pulses whenever they transmit information.



    http://www.scienceblog.com/cms/physi...ely-12738.html

    http://matpitka.blogspot.com/2008/02...i-soliton.html

    http://en.wikipedia.org/wiki/Soliton


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  3. #2  
    Forum Cosmic Wizard spuriousmonkey's Avatar
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    Have you got any real references?


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  4. #3  
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    The article from the first of the three links, has in turn a link the University of Copenhagen. So, a quick search for the word "soliton" in their search box gives you a list of links, most of which have to do directly with the subject.

    http://search.ku.dk/?q=soliton

    I opened the first one on the list, which was: www.fys.ku.dk/~karreg/Gomadingen2006ver2.ppt and it pretty much describes everything I was posting about. Now, unless you've really got a good face value reason to doubt, it would be annoying for you to ask for more confirmation than that.

    What would be more constructive would be for you to explain to me why you doubt it so much. I'm pretty sure the third link I posted goes into some detail about what holes exist in the soliton hypothesis. I'm curious if anyone knows of other reasons why it wouldn't be likely to be true?
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    i meant references for your claims.
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  6. #5  
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    Quote Originally Posted by spuriousmonkey
    i meant references for your claims.
    What claims are you talking about? The claim that solitons carry the information instead of electricity? The links exactly describe that claim, almost in the same words, even, as well as some of the evidentiary basis. What else do you want? Copenhagen University is where the original research happened, so if posting a link to a list of their own articles isn't good enough for you then... nothing ever will be.

    What will it take before the actual topic gets discussed? I'm curious what implications the theory has, assuming it were true. For example: I wonder if it would change the likelihood of being able to reconnect severed spinal cords? Stuff like that.
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  7. #6  
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    this one.

    here seems to be a new emerging theory about the way information is transmitted in the human nervous system.
    "Kill them all and let God sort them out."

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  8. #7  
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    Quote Originally Posted by spuriousmonkey
    this one.

    here seems to be a new emerging theory about the way information is transmitted in the human nervous system.
    Oh. That. I probably should have used the word "hypothesis" or something. I have no idea how well the scientific community is reacting to it. (And quite frankly: I don't care. I'm convinced by evidence, not group opinion, even if it's a group of "smart people")

    So, honestly? The part about it becoming popular matters more to you than the part about it having evidence to support it, or the implications it might have for helping people who've suffered paralysis? ....Talk about priorities....
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  9. #8  
    Forum Cosmic Wizard spuriousmonkey's Avatar
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    I care more about evidence than opinion.
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  10. #9  
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    Quote Originally Posted by spuriousmonkey
    I care more about evidence than opinion.
    Then how would you ever entertain a hypothesis long enough to test it?
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  11. #10  
    Forum Cosmic Wizard spuriousmonkey's Avatar
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    It's not my job to test your hypothesis. I am already testing my own hypothesis.

    Why would you expect me to do your work?
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  12. #11  
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    Quote Originally Posted by spuriousmonkey
    It's not my job to test your hypothesis. I am already testing my own hypothesis.

    Why would you expect me to do your work?

    It kind of goes without saying on a science "forum" that nobody expects you to test anything, just discuss it. Am I to understand that every scientist simply focuses on testing their own hypothesis? Nobody ever discusses another scientist's hypothesis with them to help them refine it before testing?

    You ever consider how much money could be saved if people would collaborate with each other to help refine the test before money is actually spent to set it up? Makes me wonder how many hypothesis with glaring errors still manage to make it to the testing phase because nobody was there to point out those errors to the person who came up with it.

    Or.... maybe you're just being obtuse.
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    Am I to understand that every scientist simply focuses on testing their own hypothesis? Nobody ever discusses another scientist's hypothesis with them to help them refine it before testing?
    not with outsiders, no. Ideas are gold. execution of ideas anyone can do.
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  14. #13  
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    Quote Originally Posted by spuriousmonkey
    Am I to understand that every scientist simply focuses on testing their own hypothesis? Nobody ever discusses another scientist's hypothesis with them to help them refine it before testing?
    not with outsiders, no. Ideas are gold. execution of ideas anyone can do.

    Maybe it was a mistake to set up a Nobel Prize. Everyone is so desperate to be one of the three names, so they won't collaborate in large groups, will they? Nothing so high minded about science these days, I guess? Just a bunch of people in it for themselves.

    I couldn't care less about getting my name on a plaque. I have a cousin who recently died of complications related to being paralyzed from the neck down. I want to know what kind of hope might exist for people like him. If in the midst of bickering over who's hypothesis belongs to what, a cure is overlooked, I'm going to lose a lot of respect for the scientific community.
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    More scientist are immediately concerned with their grants. Nobel Prizes are lucky breaks.
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  16. #15  
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    Quote Originally Posted by kojax
    Quote Originally Posted by spuriousmonkey
    Am I to understand that every scientist simply focuses on testing their own hypothesis? Nobody ever discusses another scientist's hypothesis with them to help them refine it before testing?
    not with outsiders, no. Ideas are gold. execution of ideas anyone can do.

    Maybe it was a mistake to set up a Nobel Prize. Everyone is so desperate to be one of the three names, so they won't collaborate in large groups, will they? Nothing so high minded about science these days, I guess? Just a bunch of people in it for themselves.

    I couldn't care less about getting my name on a plaque. I have a cousin who recently died of complications related to being paralyzed from the neck down. I want to know what kind of hope might exist for people like him. If in the midst of bickering over who's hypothesis belongs to what, a cure is overlooked, I'm going to lose a lot of respect for the scientific community.
    scientists aren't interested in brain farts. They are interested in ideas that can be tested and have the promise of great insight/high impact publication (pick the option depending on how skeptical you are)
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  17. #16  
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    Ok. The theory of soliton waves as the carriers of nerve signals should be very testable, depending on how many animals you're willing to kill in the process. We can cut them open, sever nerves, insert things that would normally make good wave carriers between one end of the nerve and the other, and see if part of the signal is able to cross the medium.

    It's kind of delicate, because solitons are custom designed for the medium they're traveling in (which appears to be similar to olive oil), but it's definitely falsifiable.
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  18. #17  
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    you make the basic fallacy in assuming that currently the field of neuronal biology is missing something that needs explaining which can be explained by your idea.
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  19. #18  
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    Quote Originally Posted by spuriousmonkey
    you make the basic fallacy in assuming that currently the field of neuronal biology is missing something that needs explaining which can be explained by your idea.
    It's missing how to reconnect severed spinal cords. If it turns out that the information is traveling in waves of any kind, then all kinds of new possibilities open up.

    A wave can be lensed. Not solitons specifically, but we might be able to convert the soliton into an ordinary wave and then lens it. (really a group of waves of different frequency, but still..) There's no rule that requires us to connect the nerves exactly the way they were originally, in the same pathways they had before. The brain can rewire itself to adapt to a new configuration. You just have to create a situation where each nerve above the break connects to a nerve below the break, so that it's able to send information to just that one nerve unambiguously, without hitting the others.

    For a wave signal, that situation is way easier to create than it is for an electrical signal. It wouldn't be quite as simple as just sticking a lens between the two ends, of course, but the possibilities are much more inviting, and hopeful.
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    What I mean is, that if you had two bundles of a million wires, and you wanted to connect them across a gap, and they're carrying an electric signal, then you'd basically need to stick another bundle of a million wires between them to connect most (but not all) of them to each other (because some wires might not line up right with each other).

    If instead, those wires are carrying a wave signal, then you could place a medium for the wave to propagate in, with a lens in the middle, and it would accomplish the same effect. Each emitted wave would find its way to one, and exactly one, recipient wire.

    Anyway... that's true if we were talking about a machine. I have no idea whether it would work with human nerve tissue. I'm not sure what it takes to stimulate a nerve, and I read somewhere that severed spinal nerves develop some kind of a callous that makes it difficult to even stick them physically back together.
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  21. #20  
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    Quote Originally Posted by kojax
    I'm not sure what it takes to stimulate a nerve
    Depolarization.

    Here is a good primer: http://faculty.washington.edu/chudler/ap.html


    It's not really analogous to electrons moving down a copper wire, so if you think it is, that could be part of your misunderstanding.

    In addition to the above, here's another good one: http://outreach.mcb.harvard.edu/anim...npotential.swf
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  22. #21  
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    Quote Originally Posted by inow
    Quote Originally Posted by kojax
    I'm not sure what it takes to stimulate a nerve
    Depolarization.

    Here is a good primer: http://faculty.washington.edu/chudler/ap.html


    It's not really analogous to electrons moving down a copper wire, so if you think it is, that could be part of your misunderstanding.

    In addition to the above, here's another good one: http://outreach.mcb.harvard.edu/anim...npotential.swf
    Thanks! This is the first useful response I've gotten on this thread. Those links do a very good job of explaining the basics, so I have a good basis to start expanding my understanding.

    Each cell triggering the next kind of makes sense under both paradigms, but the electrical version of the story seems slightly more parsimonious. I'll have to read more on the soliton theory now to see how it corresponds, if it does at all.
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  23. #22  
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    Quote Originally Posted by kojax
    Quote Originally Posted by spuriousmonkey
    you make the basic fallacy in assuming that currently the field of neuronal biology is missing something that needs explaining which can be explained by your idea.
    It's missing how to reconnect severed spinal cords. If it turns out that the information is traveling in waves of any kind, then all kinds of new possibilities open up.

    A wave can be lensed. Not solitons specifically, but we might be able to convert the soliton into an ordinary wave and then lens it. (really a group of waves of different frequency, but still..) There's no rule that requires us to connect the nerves exactly the way they were originally, in the same pathways they had before. The brain can rewire itself to adapt to a new configuration. You just have to create a situation where each nerve above the break connects to a nerve below the break, so that it's able to send information to just that one nerve unambiguously, without hitting the others.

    For a wave signal, that situation is way easier to create than it is for an electrical signal. It wouldn't be quite as simple as just sticking a lens between the two ends, of course, but the possibilities are much more inviting, and hopeful.
    severed spinal cords are reconnected by new axon growth.
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  24. #23  
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    Quote Originally Posted by spuriousmonkey
    Quote Originally Posted by kojax
    Quote Originally Posted by spuriousmonkey
    you make the basic fallacy in assuming that currently the field of neuronal biology is missing something that needs explaining which can be explained by your idea.
    It's missing how to reconnect severed spinal cords. If it turns out that the information is traveling in waves of any kind, then all kinds of new possibilities open up.

    A wave can be lensed. Not solitons specifically, but we might be able to convert the soliton into an ordinary wave and then lens it. (really a group of waves of different frequency, but still..) There's no rule that requires us to connect the nerves exactly the way they were originally, in the same pathways they had before. The brain can rewire itself to adapt to a new configuration. You just have to create a situation where each nerve above the break connects to a nerve below the break, so that it's able to send information to just that one nerve unambiguously, without hitting the others.

    For a wave signal, that situation is way easier to create than it is for an electrical signal. It wouldn't be quite as simple as just sticking a lens between the two ends, of course, but the possibilities are much more inviting, and hopeful.
    severed spinal cords are reconnected by new axon growth.
    If the people working on it can get that method to work, then I must totally agree that it would be the best way. Sort of like if genome researchers find a way to regrow severed limbs, then there would be no need to continue trying to develop better prosthetic limbs.

    In the meantime, I think most people with paralysis would be happy with a less-than-ideal solution as long as it works reasonably well, rather than watch decades of their life tick away while they wait for the perfect solution.
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    Why don't you consider just new hardwiring instead of a technique that isn't even close to being mainstream and functional?

    And if it was as easy as reconnecting you would think someone would have done it already wouldn't you?

    One problem is that axons are part of a cell. And if they get severed they are missing a cell body.

    Your fancy waves aren't going to change that.
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  26. #25  
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    Quote Originally Posted by spuriousmonkey
    Why don't you consider just new hardwiring instead of a technique that isn't even close to being mainstream and functional?
    Hard wiring would require incredibly thin wires, and each wire would have to be insulated from the others.


    And if it was as easy as reconnecting you would think someone would have done it already wouldn't you?
    Good point. In a paralytic's situation, you could simply remove one of their vertebrae, thus shortening their back by an inch or two, and reconnect the severed ends. Clearly the task is not quite that simple.
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  27. #26  
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    Quote Originally Posted by kojax
    Quote Originally Posted by spuriousmonkey
    Why don't you consider just new hardwiring instead of a technique that isn't even close to being mainstream and functional?
    Hard wiring would require incredibly thin wires, and each wire would have to be insulated from the others.
    Or, you could use computer-assisted data transfer. Put a patch on one area, and a patch on another, and you can effectively "jump over" the part of the nerve bundle which is severed. Much of this technology is already in place with the higher-end prosthetic limbs.
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  28. #27  
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    and now back to biological reality.
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  29. #28  
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    Spurious,
    instead of taking cheap snipes at the research Kojax has happened upon, ... No, wait a moment. You are taking cheap snipes at Kojax for having entertained consideration of a hypothesis that is not mainstream, purely - it seems - because it is not mainstream.
    Since you are so committed to evidence - an admirable trait - why not cite the single aspect of the work you find leas tconvincing?

    O.
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  30. #29 Re: Nerves - electric, or sonic? 
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    Quote Originally Posted by kojax
    On the other hand, the existing electrical theory is supported by the fact the nerves are clearly observed to give off electrical pulses whenever they transmit information.
    I think this is the major problem with this new hypothesis. How do they account for all the (direct) evidence that electricity is involved in neural communication?

    You can put an electrode in a monkey brain and record electric activity as the cells work. Transcranial magnetic stimulation also affects the function of certain regions of the brain. And there were recent experiments where electrical stimulation on the rat's spinal cord were shown to relief symptoms associated to Parkinson's -- namely the lack of voluntary motor control.

    I would like to hear more about this hypothesis, but I really doubt it would flourish to anything more solid and based on more direct evidence.
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  31. #30 Re: Nerves - electric, or sonic? 
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    Quote Originally Posted by Kadu
    Quote Originally Posted by kojax
    On the other hand, the existing electrical theory is supported by the fact the nerves are clearly observed to give off electrical pulses whenever they transmit information.
    I think this is the major problem with this new hypothesis. How do they account for all the (direct) evidence that electricity is involved in neural communication?

    You can put an electrode in a monkey brain and record electric activity as the cells work. Transcranial magnetic stimulation also affects the function of certain regions of the brain. And there were recent experiments where electrical stimulation on the rat's spinal cord were shown to relief symptoms associated to Parkinson's -- namely the lack of voluntary motor control.

    I would like to hear more about this hypothesis, but I really doubt it would flourish to anything more solid and based on more direct evidence.
    What I'm starting to consider is the possibility that it's just an ordinary sound wave, rather than a soliton, and the nerves are basically acting as amplifiers.

    Working from inow's links, if the neuron consists in two opposite electrical charges separated by a membrane, then... if the neuron is struck by a sound wave that deforms its shape, portions of the outer and inner portion will be pushed closer together, which increases the electric force of their charges on each other, triggering the rest of the events.

    Then, as the cell moves from a 70 millivolt difference to a 55 millivolt difference and back, that would deform the cell's shape again. If it happens quickly enough and forcefully enough, then it would cause a new shock wave to be emitted.
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  32. #31  
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    Quote Originally Posted by Ophiolite
    Spurious,
    instead of taking cheap snipes at the research Kojax has happened upon, ... No, wait a moment. You are taking cheap snipes at Kojax for having entertained consideration of a hypothesis that is not mainstream, purely - it seems - because it is not mainstream.
    Since you are so committed to evidence - an admirable trait - why not cite the single aspect of the work you find leas tconvincing?

    O.


    Please show evidence that axons can be separated from the cell body, survive, and emit sonic beams/waves. You can't step over biological realities because you entertain the notion that something new is interesting.

    If there is no biological relevance, then any hypothesis has a major issue to start with.

    I can happily start the hypothesis that nerves can transduce a signal by means of light signals as an alternative hypothesis to meanstream thought.

    Doesn't mean that it is a viable hypothesis.

    Why do you try to find evidence that supports the hypothesis? That's the whole idea behind a new hypothesis. That it is actually based on some set of relevant observations.
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  33. #32  
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    Quote Originally Posted by spuriousmonkey
    Quote Originally Posted by Ophiolite
    Spurious,
    instead of taking cheap snipes at the research Kojax has happened upon, ... No, wait a moment. You are taking cheap snipes at Kojax for having entertained consideration of a hypothesis that is not mainstream, purely - it seems - because it is not mainstream.
    Since you are so committed to evidence - an admirable trait - why not cite the single aspect of the work you find leas tconvincing?

    O.


    Please show evidence that axons can be separated from the cell body, survive, and emit sonic beams/waves. You can't step over biological realities because you entertain the notion that something new is interesting.
    I just described the emission of sonic waves in my last post. If you've got two oppositely charged portions separated by a membrane, and you change the relative charge between those two portions, you're changing how hard they push on that membrane.

    A loud speaker works by altering the amount of current that goes to an electro-magnet, which in turn pulls with rapidly varying force on a surface, creating sound. The only difference with a nerve cell is that you're using the electric force instead of a magnetic force. Whether a sound wave is emitted or not depends on how strong these electric forces are, and how rapidly they are changing.

    I don't know what you mean about separating axons from a cell, however. Is the separations of axons something that happens in spinal injuries?
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  34. #33  
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    http://en.wikipedia.org/wiki/Axon

    An axon or nerve fiber is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron's cell body or soma.

    During spinal injury the axons get severed from the cell body.

    Axons don't survive on their own. They need the cell body.

    A spinal injury isn't about sending a signal from one part of the injury to the other. The axon was connected to the proper cell. This specific connection is now gone.

    A new proper connection has to be made between two specific cells.

    They have had some success in animal models by growing new axon connections that bridge the gap of the injury. But they still need to make connections to the proper cells for a proper/useful signal to be propagated.

    The sonic theory doesn't address this essential problem. And essential is really essential and not some trivial problem that shouldn't be the core of the problem.

    New theories are fine, but they should be dedicated to biological reality.
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  35. #34 Re: Nerves - electric, or sonic? 
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    Quote Originally Posted by kojax
    There seems to be a new emerging theory about the way information is transmitted in the human nervous system. I'm not sure I fully understand the theory, but it seems to predict that information is carried using soliton sound waves that travel down the nerve instead of electric pulses.

    They make some compelling arguments in these articles, like pointing out that olive oil is very similar to the chemicals believed to be carrying the sound wave, and most anesthetics have in common the trait of being soluble in olive oil. (Raising or lowering the boiling point of a substance, by dissolving something in it, would affect how sound travels through it. )

    On the other hand, the existing electrical theory is supported by the fact the nerves are clearly observed to give off electrical pulses whenever they transmit information.



    http://www.scienceblog.com/cms/physi...ely-12738.html

    http://matpitka.blogspot.com/2008/02...i-soliton.html

    http://en.wikipedia.org/wiki/Soliton
    Electrical impulses, my friend..not sound waves. That's a well documented fact.
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  36. #35  
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    Quote Originally Posted by spuriousmonkey
    http://en.wikipedia.org/wiki/Axon

    An axon or nerve fiber is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron's cell body or soma.

    During spinal injury the axons get severed from the cell body.

    Axons don't survive on their own. They need the cell body.

    A spinal injury isn't about sending a signal from one part of the injury to the other. The axon was connected to the proper cell. This specific connection is now gone.

    A new proper connection has to be made between two specific cells.
    Reading the link really helped. If I understand correctly then basically these very long axons act like telephone lines, and the nerves are just relays that amplify the signal (or start the signal).

    If so, then sonic theory is not much more helpful than electric theory. Sound waves are still easier to work with than electrical impulses, but it really doesn't matter without those telephone lines.
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  37. #36  
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    Maybe you should look for different active sites.

    As the brain.


    Not that I know of any missing link in the transduction of signals that need this kind of explanation, but it isn't my theory.
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    Well, since it doesn't solve the axon problem, I guess it's not of much use, but the fact that nerves are already adequately explained by electrical theory is certainly no reason not to explore other avenues.

    Having an explanation for everything is the goal of religion, not science. The goal of science is to be sure of our explanations (rather than relying on faith), and the best way to be sure of our explanations is to pursue every credible avenue, until there are none left. If sonic is able to parallel electric, in terms of its credibility, then we'd best not choose either one of them arbitrarily, until some kind of evidence emerges, and compels us to favor one over the other.
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  39. #38  
    Veracity Vigilante inow's Avatar
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    It's better described as chemo-electrical... not electrical... and we are rather confident since we've been studying it for over a century. :wink:
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  40. #39  
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    The first thing I would like to do is supply you with the 'real' reference that many have requested. This article is published in PNAS (Proceedings of the National Academy of Sciences) back in July 2005:

    http://www.pnas.org/content/102/28/9790.full

    Many of you might not be able to access the article because it depends upon your institution/university subscription status. If you can access it, then read it before making conclusions! I have copied the freely available abstract at the bottom of this message for you to read. This journal is the third most read journal for biologists after Nature and Science. So it is very prestigious. The writers of the article also come from the Niels Bohr institute in Denmark, which is a very respected scientfic institute.

    PNAS has a special 'Communication by proxy' route to publication where any member of the National Academy of Science (a highly prestigious position to be elected to) can put forward someone's work and it will be fast-tracked. The idea of this is to enable PNAS to publish highly controversial theories that would not otherwise survive a standard peer review process that all published science goes through. This paper went through this comminication route.

    I should add that I am an electrical engineer and neuroscientist by background and I actively perform experiments on nerve cells for my PhD.

    There seems to be confusion here about what a soliton is, so I will try to explain. If a pulse of light is released in space, then over time/distance it will spread out (disperse). However, imagine that I have a special glass that has a nonlinearity that changes its refractive index depending on the brightness of light passing through it. This is possible if the local heating effect due to light loss in the glass causes some crystal rearrangement in the glass and a change in index of refraction. The speed of light depends upon the index of refraction. Now, imagine that some photons at the front of the pulse decide to speed up a little and reach ahead of the pulse, this might cause more heating at the front of the pulse and cause those photons to slow down and rejoin the wave. Therefore, the pulse does not spread out. This has huge potential for fiberoptics where the amount of information you can pass through a cable is limited by 'pulse broadening' - a '00100' message will start looking like a '01110' message.

    I will do my best to explain the evidence for the existence of solitons in nerve cell transmission. This information comes from the PNAS paper.

    -----------------------
    1) The axon is surrounded by a lipid bilayer which has a 'gel-like' behaviour at low temperatures and a 'liquid-like' behaviour at higher temperatures. Our cells act at a temperature that is near a transition between these two states.

    2) When an electrical action potential fires, there is a measurable change in temperature and membrane properties. Reference: Abbott, B. C., Hill, A. V. & Howarth, J. V. (1958) Proc. R. Soc. London Ser. B 148, 149187. Furthermore, this temperature increase is rapidly followed by a temperature cooling. Imagine how sound wave propagation speed would vary between hot a cool regions on the membrane and see how this could create a soliton.

    3) The paper then proceeds to demonstrate solitons propagating in lipids and derives mathematical relations to discuss their various properties with temperature. It uses E.Coli, not nerve cells for these experiments

    ***Crucial Points***
    4) Many of you have asked what limitations exist in the current electrical model of neurons that could suggest a new hypothesis is needed. The paper cites these issues:

    a)nerve pulses can also be obtained in the absence of sodium or other monovalent cations in the external medium (Ref: Tasaki)

    This one seems quite surprising indeed. I would think that reducing K+ conductance could cause an action potential, but they say that even in the absence of other ions, pulses can exist. The only other targets seem to be Cl- (an anion) and chloride channels are involved in signaling in neurons. I wonder if they took these into account?

    b) tetrodotoxin, believed to block the sodium channel, alters the
    excitibility of nerves even in the absence of sodium.

    This is also interesting - but if tetrodotoxin was a partial agonist/antagonist of K+ channels, this would also alter excitability.

    c) Action potentials result in a rise and equal fall in heat, suggesting no net heat transfer ('adiabatic' in chemspeak) and isentropic. The electrical dogma of action potentials describes ions flowing down their electrochemical gradients. This should cause an increase in entropy and result in a net release of heat - but this is not found to be the case in experimental studies. A soliton, on the other hand, would cause no net release of heat.

    *** End of crucial points ***

    Overall, I do not find this work to be entirely convincing. My impression is that physiological temperature is not regulated well enough to hold the membrane in the correct region of non-linearity. However, it is certainly an interesting a daring attempt to undermine the dogmatic Hodgkin-Huxley electrical model of neurons.

    --------------------------PNAS PAPER ABSTRACT--------------------------------
    "The lipids of biological membranes and intact biomembranes
    display chain melting transitions close to temperatures of physiological
    interest. During this transition the heat capacity, volume
    and area compressibilities, and relaxation times all reach maxima.
    Compressibilities are thus nonlinear functions of temperature and
    pressure in the vicinity of the melting transition, and we show that
    this feature leads to the possibility of soliton propagation in such
    membranes. In particular, if the membrane state is above the
    melting transition solitons will involve changes in lipid state. We
    discuss solitons in the context of several striking properties of
    nerve membranes under the influence of the action potential,
    including mechanical dislocations and temperature changes."
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  41. #40  
    Forum Professor marcusclayman's Avatar
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    I learned this magic encantation to conjure scientific studies, without affiliations

    first you need an online search engine, then you need the name of the study: enter the name into the search bar and then click search

    Here is the study masscott is refering to, if you can't access it from his link

    http://www.scribd.com/doc/21195625/O...nes-and-Nerves

    Interesting hypothesis, I'll need to read up on it. Makes me think about the almost mystical effects correlated with sound and music by different ideologies.
    Dick, be Frank.

    Ambiguity Kills.
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  42. #41  
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    Excellent website marcus. I will have to recommend this to my colleagues
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  43. #42  
    Universal Mind John Galt's Avatar
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    Quote Originally Posted by mascott
    http://www.pnas.org/content/102/28/9790.full

    Many of you might not be able to access the article because it depends upon your institution/university subscription status.
    PNAS articles are available to everyone after one year or eighteen months- I don't recall which, so there will be no difficulty accessing this one. (Selected articles are also freely available at the time of publication.)
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  44. #43  
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    I'm starting to think the value of this theory is not so much in what it will teach us about how to repair the nervous system, by studying solitons and waves, as in what we might learn about how to create solitons and sound waves by observing the nervous system.

    Sort of like how the study of bats/dolphins.. etc use of sonar may have taught us something about how to create sonar machines of our own.

    I'm sure wave physicists already know how to do everything we're observing to some degree or another, but it's possible that we'll find the body has perfected it in ways we haven't yet. I'd certainly love the be the guy filing patents off of that research.
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  45. #44 sorry 
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    hey sorry but i have to ask and check because im still at school. what excatly are sonic waves? im assuming its like sound waves
    just wondering
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  46. #45 Re: sorry 
    Time Lord
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    Quote Originally Posted by zendra
    hey sorry but i have to ask and check because im still at school. what excatly are sonic waves? im assuming its like sound waves
    Yeah. They're the same thing.
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