Physicists challenge notion of electric nerve impulses; say sound more likely

Danish scientists challenge the accepted scientific views of how nerves function and of how anesthetics work. Their research suggests that action of nerves is based on sound pulses and that anesthetics inhibit their transmission.

Every medical and biological textbook says that nerves function by sending electrical impulses along their length. “But for us as physicists, this cannot be the explanation. 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,” says associate professor Thomas Heimburg from the Niels Bohr Institute at Copenhagen University. He received his Ph.D. from the Max Planck Institute in Göttingen, Germany, where biologists and physicists often work together – at most institutions these disciplines are worlds apart. Thomas Heimburg is an expert in biophysics, and when he came to Copenhagen, he met professor Andrew D. Jackson, who is an expert in theoretical physics. They decided to work together in order to study the basic mechanisms which govern the way nerves work.

Physics explains biology

Nerves are ‘wrapped’ in a membrane composed of lipids and proteins. According to the traditional explanation of molecular biology, a pulse is sent from one end of the nerve to the other with the help of electrically charged salts that pass through ion channels in the membrane. It has taken many years to understand this complicated process, and a number of the scientists involved in the task have been awarded the Nobel Prize for their efforts. But – according to the physicists – the fact that the nerve pulse does not produce heat contradicts the molecular biological theory of an electrical impulse produced by chemical processes. Instead, nerve pulses can be explained much more simply as a mechanical pulse according to the two physicists. And such a pulse could be sound. Normally, sound propagates as a wave that spreads out and becomes weaker and weaker. If, however, the medium in which the sound propagates has the right properties, it is possible to create localized sound pulses, known as “solitons”, which propagate without spreading and without changing their shape or losing their strength.

The membrane of the nerve is composed of lipids, a material that is similar to olive oil. This material can change its state from liquid to solid with temperature. The freezing point of water can be lowered by the addition of salt. Likewise, molecules that dissolve in membranes can lower the freezing point of membranes. The scientists found that the nerve membrane has a freezing point, which is precisely suited to the propagation of these concentrated sound pulses. Their theoretical calculations lead them to the same conclusion: Nerve pulses are sound pulses.

Anesthetized by sound

How can one anesthetize a nerve so that feel ceases and it is possible to operate on a patient without pain? It has been known for more than 100 years that substances like ether, laughing gas, chloroform, procaine and the noble gas xenon can serve as anesthetics. The molecules of these substances have very different sizes and chemical properties, but experience shows that their doses are strictly determined by their solubility in olive oil. Current expertise is so advanced that it is possible to calculate precisely how much of a given material is required for the patient. In spite of this, no one knows precisely how anesthetics work. How are the nerves “turned off”? Starting from their theory that nerve signals are sound pulses, Thomas Heimburg and Andrew D.

Jackson turned their attention to anesthesia. The chemical properties of anesthetics are all so different, but their effects are all the same – curious!

But the curious turned out to be simple. If a nerve is to be able to transport sound pulses and send signals along the nerve, its membrane must have the property that its melting point is sufficiently close to body temperature and responds appropriately to changes in pressure. The effect of anesthetics is simply to change the melting point – and when the melting point has been changed, sound pulses cannot propagate. The nerve is put on stand-by, and neither nerve pulses nor sensations are transmitted. The patient is anesthetized and feels nothing.

From University of Coppenhagen

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39 thoughts on “Physicists challenge notion of electric nerve impulses; say sound more likely”

  1. If the nervous system is based on sound, it almost makes sense that music and rhythm can effect the body in such a way that it does.

  2. IF electricity is not controlling the muscles that what is? and why a patient with a heart attack is given electrical shock to his heart to make it beat again, hope this explains the electricity in the body….

  3. maybe all energys such as electricity, sound, light, and the rest of it all come down to a single energy.

    on here people have said.. “if nerve are controlled by electricity wouldnt there be a cure for Reflex Sympathetic Dystrophy”.. this would rely on nervs being completley electrical. OR things like “Hearing implants are designed to use electrical impulses to allow subjects to crank up amplification of sounds”

    Einstien once said “A man should look for what is, and not for what he thinks should be.” and being the most famous man for his inventions and discouverys i believe we should take a leaf out of his book and look, not think, outside the box.

    tv’s / radios DO NOT simply SHOW electricity produces sound.. but what they do SHOW is that electricity is COMPATIBLE with sound. also frequency waves SHOW electicity is compatible with sound (FREQUENCY). now you may be thinkin what i have been thinkin, then that would mean that sound would have to be able to convert to electricity.. YES IT CAN.

    Electro-mechanical microphones use a small diaphram attached to a coil of wires suspended in a magnetic field. When the vibrations in the air cause cause the diaphram to vibrate, the movement of the coil of wire in the magnetic field generates a small electric current.

    i believe these two FACTS should show electricity doesnt just generate sound, and sound doesnt just generate electricity. what it does show is that they can also COME AS A PAIR, can be produced at the same time and also BY THE SAME MECHANICAL DEVICES.

    basically, it could either be we use sound and electricity at the same time in our nerves. or it could mean that we simply use neither, we use a seperate energy that we do not yet know, and the results we are picking up on (telling us it is either sound or electricity) could be the waste products emitting through sound and electricity charactoristics. not actualy sound or electricity itself.

    think of it as a Tree.. we can not see the routes of a tree because they are burried (in this case the roots being the energy we do not yet know that produces sound and electricity waste.) now what we do know is it gives us apples, as many apples as we need.. (apples being sound and electricity.) still we have not yet dug any deeper to relise that the apples (sound and electricity) would not be there with out the foundations of the ROOTS (the new energy) being in the ground where we can not see it.

  4. I read recently that the purpose of the appendix is to harbour desired endogenous bacteria so as to be able to re-seed the colon when necessary

  5. of course it’s a reason for many surgeries as it gets inflammed, but tere’s a reason for existence of every human part.For example you can’t cut out the appendix from a very small child(don’t remember exactly the age)as the the digestive tract microflora develops there and a chilld’s digestion would be severly impaired(if not impossible)if he had appendectomia in an early age.The same is with thymus-it exists until around 12 years of age, later disappears.

  6. This theory seems to contradicts the entire structure of the nerve. Because in most cases with the human body everything is there for a reason. (with exception to the appendix) Nerves are equipped with a myelin sheath to help aid in the quickening of impulses sent between nerves. It aids as an insulator for the electrical impulses, which explains why impulses are slower on un-myelinated nerve cells. So with this theory it would make a major part of the nerve cell seemingly useless and for billions of cells in our body to have a completely useless feature seems overly far fetched.

    • not at all.if no heat is generated by the current flow, then this violates the laws of thermodynamics. on the other hand, this theory actually supports the Hodgkins-Huxley theory of nerve impulses by accounting for the lack of heat created by the current flow. is it also really that far fetched to say that the body has redundant mechanisms for ensuring that these all important signals reach their targets?

  7. Relatively loud sounds are audible in air. These are much much smaller amplitude and are contained waves in nerve fibers. Calling them sound waves just means that they’re a certain kind of longitudinal wave in a medium. That’s very different from them being macroscopic waves in air that our ears are sensitive to.

  8. The entire idea of science is to look at a process, come up with a hypothesis that could explain it, and to then test the hypothesis via experimentation.

    these scientists have come up with a hyposthesis and presumably will try to test it. it is an interesting idea, and understanding it requires knowledge of the biochemistry and biophysics of membranes, and the physics of sound in microscopic conditions. it may be hard to do the experiments. it may be impossible to produce evidence. but if they can accumulate data to support their hyposthesis, the burden of evidence will lead other scientists to use the idea as a reasonable explanation.

    the number of people who laughed at this hypothesis in the preceeding comments is concerning. to ridicule a new idea is not part of the scientific process. it is at least bad playground behavior. worse, it turns knowledge into faith, an unassailable wall that stifles intellectual curiosity and creative thinking. history is filled with examples of how badly that turns out. if you don’t think an idea is correct you should do the experiments to disprove it, or wait for the proponent to give evidence. in fact, you should do the same thing if you believe in the idea. it is the only way that science can move forward. remember einstein and quantum mechanics. the burder of evidence gives us an approximation of the truth, and every scientific idea is testable, by definition.

  9. There was a soliton theory of muscle contraction put forth about 15 years ago and that never got anywhere, either. Maybe it was soliton sound wave that produced the ripping sound of my hernia in the gym recently… ;)

    “The scientists found that the nerve membrane has a freezing point, which is precisely suited to the propagation of these concentrated sound pulses.” Proposing that the lipid membrane of the neuron and the seperate cell providing myelination are “freezing” to propagate sound waves needs some EVIDENCE.

  11. Hmm. To put it in a simple way…How does one spell “Urban Legend”?

    I applaud you for the effort. But sometimes I have to shake my head in disbelief as to HOW brilliant minds can put all that mental super-goo to waste…?

    Really. One factor of science that is often omitted (I’ve been guilty of it), is relevance…nerve impulses, sound??? Come on…really.

    • because we can’t hear that particular wavelength. in fact we cant here most sounds. just because we cant here it doesn’t mean its not sound. and this is sound through a lipid medium, not through air. and how would you electronically measure the propagation of a sound wave through such a fragile two dimensional layer without disturbing it?

  12. The transducing of electrical to acoustic waves via solitons is not something new and was discussed in extensive detail by Frank Barr, who pioneered (alone) the concept of neuromelanin and its effect on information propagation in the nervous system.

    Barr FE. Melanin: the organizing molecule.Med Hypotheses. 1983 May;11(1):1-139.
    The hypothesis is advanced that (neuro)melanin (in conjunction with other pigment molecules such as the isopentenoids) functions as the major organizational molecule in living systems. Melanin is depicted as an organizational “trigger” capable of using established properties such as photon-(electron)-phonon conversions, free radical-redox mechanisms, ion exchange mechanisms, and semiconductive switching capabilities to direct energy to strategic molecular systems and sensitive hierarchies of protein enzyme cascades. Melanin is held capable of regulating a wide range of molecular interactions and metabolic processes primarily through its effective control of diverse covalent modifications. To support the hypothesis, established and proposed properties of melanin are reviewed (including the possibility that (neuro)melanin is capable of self-synthesis). Two “melanocentric systems”–key molecular systems in which melanin plays a central if not controlling role–are examined: 1) the melanin-purine-pteridine (covalent modification) system and 2) the APUD (or diffuse neuroendocrine) system. Melanin’s role in embryological organization and tissue repair/regeneration via sustained or direct current is considered in addition to its possible control of the major homeostatic regulatory systems–autonomic, neuroendocrine, and immunological.

  13. Freezing is a state change from liquid to a more solid state. Depending on the additional items in an oil solution, it can be very high temperatures where this state change happens. The fulltext article (linked elsewhere in this chain of comments) spells things out in rather more detail.

  14. This hypothesis has been around for decades and the study of it has failed to generate enough positive data to lead us to believe that sound waves instead of ion flux is how impulses are generated. Just because we don’t know yet how many anesthetics work at the molecular level doesn’t mean that they have to work by inhibting sound waves. We don’t know how gravity works either but that doesn’t mean that current theories of gravity are worthless, it just means we don’t have the right foundation of knowledge or the right tools to understand it yet.

  15. I don’t know what this guy is up to, but we know exactly how nerves work. Do you have a link to the actual article?


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