Post by: gunug on March 10, 2007, 03:21:41 AM
QUOTE
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.
"For us as physicists, this cannot be the explanation," said Thomas Heimburg, an associate professor at the university's Niels Bohr Institute. "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."
"For us as physicists, this cannot be the explanation," said Thomas Heimburg, an associate professor at the university's Niels Bohr Institute. "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."
http://www.cbc.ca/technology/story/2007/03...d-20070309.html
I have a condition called Neuropathy and I have had what seems like hours of tests where they shock me or monitor electrical activity in my nerves. I'm not sure where these guys are going with this! Anyone else have thoughts about this?
QUOTE
Heimburg and Jackson theorize that sound propagation is a much more likely explanation. Although sound waves usually weaken as they spread out, a medium with the right physical properties could create a special kind of sound pulse or "soliton" that can propagate without spreading or losing strength.
Post by: tacit on March 10, 2007, 03:05:28 PM
However, neither is correct. The idea that electricity runs along your nerves is popular in science fiction, but it is not correct.
A normal nerve cell in its resting state is "hyperpolarized." It has a large number of charged sodium ions inside the cell--larger than the number of ions outside the cell. For this reason, there is a charge potential gradient across the membrane fo the cell.
When the cell fires, it "depolarizes." Ion channels in the cell membrane open up, and the ions rush out of the cell to equalize the concentration of ions outside and inside the cell. When the depolarization reaches the end of the cell, it stimulates the release of neurotransmitter chemicals from the end of the cell's axon. These chemicals bridge the gap to a neighboring nerve cell or to a muscle, stimulating it to depolarize (if the cell is a nerve cell) or contract (if the cell is a muscle).
After the cell has depolarized, an active ion pump mechanism switches on. This pump takes the form of a complex protein in the cell's membrane that acts as a gateway. The protein has a charged end and attracts the ions outside the cell membrane. The ions bond loosely to the protein, changing its configuration. A molecule of ATP then connects to the inside of the protein and loses a phosphate, producing energy which drives the protein to change its configuration again, drawing the ion into the cell. This "ion channel pump" resets the nerve cell to a hyperpolarized state, readying it for firing again. During the refractory period when the cell is hyperpolarizing again, it can not be made to fire again.
(My college background is in neurobiology and neurophysiology.
)
Post by: Gregg on March 10, 2007, 07:13:29 PM
Post by: gunug on March 10, 2007, 09:51:34 PM
QUOTE
...and I bet you stayed in a Holiday Inn Express last night.
Gregg - :sailed right over top of smiley's head:
Post by: eric j on March 11, 2007, 09:44:13 AM
As a mechanical engineer, all this biology stuff is really way above my head - but I remember reading some years ago that a few scientists were claiming that cells emit photons. They named them biophotons and they claimed to have detected them.
They further claimed, if I remember well, that cells could communicate among each other using this process.
Their work was not without critics and I have not followed up the topic. I suppose that Google would provide more info., but I'm too short of time just now to look.
eric j
Post by: gunug on March 12, 2007, 01:17:24 PM
Post by: Gregg on March 13, 2007, 07:30:27 AM
QUOTE(gunug @ Mar 12 2007, 01:17 PM) [snapback]121712[/snapback]
Thanks guys, all food for thought! I'm interested in what nerves do because they don't always do it so well for me!
Yeah, they've got alot of nerve!
Could give you an intermittent spasm, eh Peter?