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Scientists Say Nerves Use Sound, Not Electricity
gazzarda writes "The CBC is reporting that a team of Danish scientists are claiming that nerve impulses are transmitted by sound and not electricity. 'The common view that nerves transmit impulses through electricity is wrong and that they really transmit sound, according to a team of Danish scientists. The Copenhagen University researchers argue that biology and medical textbooks that say nerves relay electrical impulses from the brain to the rest of the body are incorrect.'"
Is it just me, or did the summary say the same thing in three slightly different ways?
Other scientists say, "These scientists are idiots."
I'm so tired of hearing the press use "scientists say" as a legitimizing opener. If you believe something because "scientists" say so, you are probably not a scientist. If you were, you would be forced to know many scientists who are idiots; scientists who no one should listen to.
Peer reviewed and agreed upon usually means good science. The CBC saying, "scientists say" means squatcum.
How do they explain all of the electrical measurements of nerve cells? We have measured voltages and currents. We know that these are dependent on certain protein channels, and salt concentrations. If impulses are actually the result of "solitons", how can they explain half a century worth of neurobiology? One wild guess, based on a minor inconsistency (if it even exists as they believe) needs a hell of a lot more evidence before they should be taken seriously.
Extraordinary claims require extraordinary evidence.
It's a series of tubes.
We apologize for the inconvenience.
I'll send you a jump to conclusions mat.
It _could_ be that the electricity is exciting the nerves and, in turn, they are sending signals(by sound)...causing loss of motor control.
There is a lot more information needed here. For those of you who haven't read the article, don't bother. Here is a summary: Some crackpots think neurons don't use electricity* because they don't get warm. Therefore, they use sound waves. First of all, there appears to be no reason to suggest sound waves. Second, sound waves are not perfect transmitters of energy either. Some of it will bleed off as heat. So it seems to me that the very reason that they think it's not electricity* precludes it from being sound waves unless neurons are somehow made of an ideal medium. IANA Neuroscientist but I have taken neuroscience classes and neurons don't conduct electricity. They open gates for ions to flow from areas of high electrical (and chemical?) potential to areas of low electrical potential, decreasing the voltage between the inside and outside of the neuron which then causes the next set of gates down the line to open. Not that I expect the article to get it right.
Rephrasing the same statement three times is actually not the same thing as elaborating on it. Repeating something three times dos not provide more information. It's wrong to think that stating something three times over will make for a better summary.
sic transit gloria mundi
IANANS, but the nerve impulses are electrochemical impulses, so they're not analogous to electrons racing down a copper wire. The chemical aspect slows things down quite a bit.
If you post it, they will read.
You need to take "Logic 101" classes. Just because muscles react to electricity (and body transmits electricity) does not prove in any way that it is necessarily electricity that is used by body to control muscles. In the same way one can conclude that just becuase body reacts to bullets means that it uses bullets internally, which is nonsense.
It's peculiar that neither of you "neuroscientists" took the opportunity to point out that neural signals are not electrical impulses--they're electrochemical state changes that propagate along nerve axons at a pretty sedate speed (measured in feet per seconds), and not any form of electrical current akin to what flows through a wire when you connect it across the poles of a battery (or pass the wire through a magnetic field, or whatever). The current in the wire travels quite a bit faster than 60 fps...
The misconception that the brain is full of little conductors, and that its operation is just like a computer, with electrical voltages and organic logic gates giving rise to "thoughts" is dear to the common mind. This misconception is responsible for the glamour exercised by one of the great follies of the age: the notion that we are in an essential and important way like computers, and that computers could be made to be--in some deeply significant way--like us.
As "neuroscientists" you know better than this, of course. The broad outlines of what happens when a neuron transmits a signal are pretty uncontroversial (though I'm sure that there are plenty of spirited arguments about the details). This article wasn't an attack on your views, but on the popular belief.
Perhaps the perpetrator of the article was trying to let a little air out of that particular balloon? Then again, I suppose my surprise would not be too great if I were to learn that some theoretical physicists are so truly dull as to think that they could teach neurophysiologists a thing or two. An interdisciplinary education is a rare phenomenon these days, and the specialists never bother talking to each other--let alone to us normal geeks.
By the way, IANANSIAAP (I am not a neuroscientist, I am a philospher.
Great men are almost always bad men--Lord Acton's Corollary
To illustrate, his most compelling argument is this: "The physical laws of thermodynamics tell us that electrical impulses must produce heat as they travel along the nerve, but experiments find that no such heat is produced."
This was when I thought he was full of shit. Any type of 'communication' requires some energy. The transduction of sound (molecules hitting one another in a propagating a pressure wave) also could produce heat in the thermodynamic argument. TFA is lacking on sufficient detail to look into this further.
it made it to PNAS as a communicated article
PNAS is funny like that... Of what I've read there, there seems to be a difference in quality between track II peer review and communicated articles. not to crap on this paper, that i havent read.
and the argument that this new biophys journal paper must be crap because it wasnt in nature or science is bullshit. good science gets published everywhere, and you do yourself a disservice by limiting your reading to popular magazines.
That wouldn't prove sound controls nerves, for it is quite common knowledge that doing something like that would upset your middle ear, so you'd lose balance and become nauseous just because of that.
Ignore this signature. By order.
The current bunch of moderators must have a horribly attenuated sense of humour. This is the first slashdot post for months and months that actually made made me fully appreciate the meaning of 'LOL', because I did! Yet it gets scored +5 'Interesting', while hordes of pathetic little jibes get +5 funny. I just don't get what makes you lot tick.
IAAPWASTEIBP (I am a physician with a sound training especially in basic physiology), and would like to comment that, while the particulars of HOW electric impulses are transmitted along nerves are not entirely relevant here, a simple test will prove THAT they are. AC current at low voltage. Touch it, see your muscles twitch, feel the paresthesia. As long as you can't explain how sound could do the same, I'll stick to currently accepted theory, thank you very much.
Sorry pal but that's how science works. There's no better evidence for a model than the fact that it explains all obtained results.
More to the point, there's no philosophically valid way to "prove" anything conclusively.
Le français vous intéresse?
And electro-shock, EEG's, retinal implants, and the old squid cell experiments where you stick electrodes in a squid neuron and measure its behavior are all based on a wrong theory, because the idiot who wrote The Fine Article can't figure out where the heat went from conduction of electricity in living matter? It's sitting inside a living organism with lots of *other* thermal processes going on: the heat generation is easily lost in the thermal noise.
I'll believe it when I see experimental evidence: but the article as presented is pretending that God makes timepieces himself because you found a watch in the desert. It's nonsense.
If you know a member of the Academy, they can sponsor your paper and get it published in PNAS. I've read tons of bad articles in PNAS that got in that way.
And while much good research is published all over the place, this is so groundbreaking that it would be a Nature paper if good enough. Nature/Science/etc publish good, "exciting" papers. Other journals publish good papers that just aren't high-profile enough for the top impact journals.
IAAN (I am a neuroscientist, yeah you knew that already) and, as they Physicist already explained, you are in fact describing electrical currents. So I agree with the other two neuroscientists, saying that the electrical models we have are wrong is just BS.
/. summary above. I'd imagine the actual paper makes a more sensible argument, but I'm not going to read that before monday, so...
There are plenty of valid criticisms you can bring to the HH model. It cannot account for all observations (there was a paper in Nature recently exactly to this point) and after all, when you try to model primate cells with HH dynamics, you are in effect comparing your monkey with a giant squid! It has tbh always amazed me how well that worked at all. So if you're going to say, HH is inadequate, that's fair. If you are going to say that non-electrical pathways for transmitting information exist alongside the known electrical currents, that's also fair and you have my complete attention. But you can't just say that nerves don't use electricity, that just labels you as someone trying to be sensationalist. Besides, if you could prove this beyond reasonable doubt, you should and would send the paper to Nature.
Then again, this is my reaction to the
Insightful gives karma, funny doesn't.
Did you know that it has been observed that the thickness of the axon's membrane changes as the nerve impulse moves through? This is a nice writeup.
Sounds are energetic compressions in a medium - a physical solid.
Electrical impulses are the flow of electric charge.
They are completely, 100% different physical phenomena.
Just looking at the transmission speeds makes it clear what is going here:
Data:
Summary: neural transmission is orders of magnitude too slow to qualify as either an electrical or sonic phenomenon.
Conclusion: TFA suggests replacing one gross oversimplification of neural transmission with another. Neural transmission might have some qualities of both but is clearly neither. TFA is garbage.
Note Bene:There is no way of knowing what the original work was talking about. I cannot imagine anyone who has studied neural transmissions saying anything like TFA's contents. I suspect that the author of TFA was presented with an anology and took it for fact.
I agree that the article is being somewhat unfairly trashed. I did a significant part of my phd thesis work on channel biophysics, and some of the things they're saying aren't as ridiculous as they initially sound. First, they say that the HH model doesn't explain everything, and I think that's probably correct. However, it doesn't claim to. It contains a number of experimentally-determined parameters about kinetics and voltage-sensitivity of gating, and it doesn't say where those parameters come from. And as of today, we can't derive those parameters from first principles and the channel structures, and there is plenty of evidence to support the idea that interaction between the channels and the lipid molecules is important. For example, membrane tension and stiffness affect voltage dependence of gating. So I guess one could say that even though the HH model doesn't explicitly take weird lipid interaction effects into account, it does so implicitly. I think that for this reason, their claim that membrane partitioning of anesthetics means that the phospholipid molecules themselves propagate the AP are highly suspect--the anesthetics could just affect the membrane properties, thereby affecting the channel properties (I haven't checked what the literature says about this, but I'm sure there's something).
The second questionable thing about their argument (as I understand it, from a cursory reading) is that it implies that membranes are constantly perched at some sort of phase transition, which is temperature dependent. Then how do they explain that invertebrate neurons fire APs over a wide range of temperatures? You can take fruit flies at 15C and move them to a 35C incubator, and they'll keep walking around just like they were before. Looking at the curves in their PNAS paper, I don't see how that's consistent with their model.
Guided by, yes. Science is, however, a method of experimentation and revission. That said, intuition tells us that object that are pushed come to a stop, and return to their "natural state" of rest... For centeries we KNEW this to be fact.
:) ).
We knew that heavier objects fall faster than light objects, it's just intuitive that they do, so it must be the case. We never tried, and we KNEW this as fact.
We thought it obvious that if the earth was moving, there would be wind and that the pigeons would fall off their perches. The earth must be static, fixed in place at the center of the universe, with the stars painted on glass spheres arround us because it's just obviously true. We KNEW this as fact.
Science taught us, don't assume because of obviousness and intution; instead make a guess and test it out. Galiello dropped many an item off the roof of buildings and found that weight of an object isn't important to how fast it falls. In fact, he realized that objects fell with a constantly increasing speed toward the earth. He discovered what everyone attributes to Newton, Gravity.
Newton, later found that objects don't "tend to the natural state" but rather remain in a state indefinatly untill acted on by an object or force. He quantified that constant rate of change and developed calculus comming from one direction (while some German guy was doing the same thing in Germany or somewhere like that
Coprenicus, Kepler, Galilleo came to realize that the Earth is not flat. That it isn't the center of the unverse, and that all the planets in the solar system orbit the sun sweeping out equal distance in equal time.
I don't see metric boatloads, VW bugs, bread boxes or anyother evidence that "proves" anything in this matter untill more experiments are carried out.
This part, I can. "Cogito, ergo sum. QED." I can't prove, however, that you exist.
Everything in the world we know as fact can be placed into this sentence and it makes logical sense:
"It is not the case that X; however, I am having all of the thoughts, feelings and experinces as if X"
Except for ones of a certian nature, that being "I think", "I feel" or "I am" statments.
Let's try it.
"It is not the case that I exist; however, I am having all of the thoughts, feelings and experinces as if I exist."
The problem: If I don't exist, then I can't be having all of the thoughts, feelings or experiences as if I did, because I would exsist to think, or feel, or experience.
Which, in true Descarte fashion I have proved, "I think, therefore I am."
Now, are you?
I can't be a tinkering with your brain, because I exist, I just proved it. Now, my proof isn't valid in your mind, if you do indeed exsist which I can't prove directly; but, if you do exist, you can work through the logic above and logically prove you exist. There are even formal symbolic proofs if you like symbolic logic.
Now, to prove your existance to me (or mine to you), Descarte would use God; which is a leap of faith that was exceptable and expected in the time he was writing. Realistically, I can't prove it to you or anyone other than me that I exsist; all I can do is offer you a choice to except that this world is real or let you search for some intrinsic truth of your own. Pragmatically, I chose to believe the world exsists, because if it didn't knowledge of anything outside myself would be impossible to obtain. In this regard, Locke's writings make sense. There is an external world, and there is our preception
Slashdot needs a way to "thumbs down" stupid articles so they disappear.