No announcement yet.

Action Of Nerves Is Based On Sound Pulses, Anesthetics Research Shows

  • Filter
  • Time
  • Show
Clear All
new posts

    Action Of Nerves Is Based On Sound Pulses, Anesthetics Research Shows

    Action Of Nerves Is Based On Sound Pulses, Anesthetics Research Shows

    Science Daily — 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.....

    Interesting. What do you think Wise? If true, could this impact the way nerve regeneration is approached.
    Last edited by antiquity; 19 Mar 2007, 11:05 PM.

    i was thinking of generating sound rather than stimulation to block and stop pain
    cauda equina


      I'm skeptical that sound plays an important part in nerve signal transmission. The electrical properties of nerves have been very carefully studied (e.g., the squid axon). However, I bet it's true that people have not "listened" very carefully to the same nerves, so I wouldn't completely dismiss the idea that sound has some very minor role in the game. It just doesn't seem likely to me.
      - Richard


        Interesting...I do notice that sometimes when an unexpected sound is created such as a pot crashing down out of the sink, or a door slamming shut, I do feel a pulse go down my legs. I am sure others do as well.
        No one ever became unsuccessful by helping others out


          Originally posted by antiquity

          Interesting. What do you think Wise? If true, could this impact the way nerve regeneration is approached.
          Antiquity, I agree with rtfdorf.

          My first reaction is that there is a great deal of evidence that electrical currents underlie conduction of nervous pulses in the nervous system. These currents are recordable, both directly as current with intracellular electrodes and indirectly as voltages expressed when the current traverses extracellular resistance, producing field potentials.

          My second response is what could have possessed these two presumably legitimate scientists, one a physicist and the other a biologist to challenge one of the best-established theories of biology. The reason, at last as given initially in the news article, was that they were unable to measure the heat change that should b associate with electrical conduction. In my opinion, this doesn't seem like a good enough reason. Their assumption concerning the magnitude of the heat generated may be wrong or their measurements may be wrong.

          My third response was, what if they are right? What are the consequences and advantages of a theory of nerve conduction based on sound? It was these third response that led me to think further about this and conclude that these authors may have proposed something interesting and potentially valid. One of the problem with the ionic channel theory of neural conduction is its failure to explain anesthesia.

          Many substances shut down nervous activity. For example, there are many gases that anesthetize people and animals. How do they do so? Well, in relatively low concentrations, they stabilize membrane. So, why should this affect neural conduction. There has always been a lot of handwaving, about how anesthetic agents affect voltage-sensitivity of membran ionic channels.

          A sound pulse theory of conduction based on solitons may explain anesthesia but unfortunately do not explain a lot of other things associated with conduction. These include how electrical currents can activate neuronal activity, the sodium, potassium, and calcium currents that occur with action potentials.

          In the end, I think that this theory is of interest but does not explain as much as it mystifies. It does raise some interesting questions about the current theory and that is good. But, as it stands, it cannot account for a lot of phenomena.