Every time someone proposes a radical rewriting of science textbooks, one needs to proceed with caution. There is so much evidence for electrical potentials in nerve cells, this sounds really fishy:
Action Of Nerves Is Based On Sound Pulses, Anesthetics Research Shows:
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.
So, why have ion channels in the first place? What are the Nodes of Ranvier for? Why invertebrates, who do not have myelin, increase the speed of tranmission by making the axon diameter larger?
Color me sceptical for now....
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wow, that should be interesting reading. It "sounds" so completely different from the machinery I have imagined based on all the long history of neuroscience I am aware of.
Those pesky physicists!
How much heat would sound propagation generate? How much does the electrical hypothesis predict? Has this been rigorously measured?
My ex-tutor Luca Turin, a world-class biophysicist and olfaction expert, assures me that this is nonsense.
Who let the physicists out without biologists? Someone fell in love with his models, I think.
I prefer to keep the mystery of anesthetics over a possible problem to measure heat in an aqueous environment.
At the university I did my previous postdoc in, we had a professor who was somewhat notorious for making very blunt commentary to guest lecturers. One comment that leaps to memory was "You have managed to ignore 27 years of elegant physiological research," or something to that effect.
These guys have topped that. Everyday there are scores of researchers recording action potentials, blocking them or triggering them with the appropriate agonists or antagonists that (to my knowledge) do not dissolve in olive oil, triggering them by injecting current into the cell, and in so many ways making it very clear that action potentials do exist.
Now these two come along and say "that's all well and good, but your theory doesn't match our expectations (and our instrumentations sensitivities), so it can't be true. Here is our more enlightened explanation."
This reminds me of another quote, which I cannot source. If anyone knows the actual quote, please, please, let me know. It goes something like this...
The only thing more arrogant than a neuroscientist trying to understand the brain/mind/conciousness is a physicist trying to understand the brain/mind/conciousness.
That being said, the relationship between olive oil solubility and anesthetic properties is actually very interesting. I have heard it before, but never gave it too much thought. Pure speculation, but is it possible that the compounds can disperse lipid rafts (thus breaking up microdomains within the cell)?