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Take it from a physics student.

December 13, 2007 by Anonymous, 1 year 47 weeks ago
Comment id: 26432

Being a physics student I am surprised by some of the replies to this article. For instance, Electrical Engineers should talk about electricity and not sound propagation.

Yes, sound is a pressure wave that propagates in all directions, most of the time. A soliton is a pressure wave that does not change shape or intensity as it moves. This is not a theory, it is a proven phenomena found in nature. Solitons also exist in light waves and even water (some types of tidal bore). Basically, the shape of the wave causes it's energy to be funneled back into itself and not dispersed.

Sound comes in different frequencies, which we hear as pitch. For instance, some voices are higher or lower depending on faster or slower frequency. Just as our eyes can only see certain wavelengths of light and can't see ultraviolet or infrared light waves, our ears can only pick up certain frequencies of sound. If there was a sound pulse from our nerves it could be outside this frequency and the amplitude so small (we're talking a scale of a nanometer) that no, we cannot hear our nerves.

This theory is misquoted a bit and if you read the paper that is linked in a comment above, it accepts that heat is produced and that electrical pulses are present. It simply says that electrical pulses cannot fully explain the observed changes in the volume and viscosity of the nerve during impulse. The theory says that the observed electrical pulse could be a byproduct of the mechanical motion of the nerve, and the myelin sheath contributes to heat release which is then almost perfect reabsorbed (which is the contradiction with thermodynamics).

Yes, the heart emits electrical impulses, but it moves too. You can attach an electrode to your arm and make it move, but screaming at it does nothing. I would infer that if the electrical signal were a byproduct of the mechanical motion, that such a signal could also cause mechanical motion in the nerve and thus move the arm. The nerve fibers that the sound wave moves through would have to be insulated (although not "perfect acoustic insulators") and only specific waves (solitons) would travel undisturbed. Otherwise, we'd all be flopping around uncontrollably from the sounds around us.

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