Yes, I meant the inner hair cells. It is my understanding that the
bending of the inner hair cells is due to fluid dynamics when the
basilar membrane and the tectorial membrane are properly positioned.
The outer hair cells are connected to the tectorial membrane.
Ken
Hugh Foley wrote:
Yes. Especially for the outer hair cells, many of which are actually
embedded in the tectorial membrane. And though they don't transduce the
incoming energy, the tip links for both outer and inner (which do
transduce) hair cells are functionally equivalent. I'd bet that some
inner hair cells find their stereocilia deflected by the tectorial
membrane, but many (most?) do not (which is the general point that Ken
is making).
Hugh
On Sep 6, 2007, at 10:42 AM, Ken Steele wrote:
Marc Carter wrote:
In this piece,
<http://www.nih.gov/news/pr/sep2007/nidcd-05.htm> the author starts
off with "Our ability to hear is made possible by way of a Rube
Goldberg-style
process in which sound vibrations entering the ear shake and jostle a
successive chain of structures until, lo and behold, they are converted
into electrical signals that can be interpreted by the brain."
That's a load of bunk. It's not a Rube Goldberg process at all. It's
an incredibly elegant impedance-matching mechanism. It's only "Rube
Goldberg" if you don't understand what the bones do.
m
Later in that same piece, the following is stated--
"When a noise occurs, such as a car honking or a person laughing,
sound vibrations entering the ear first bounce against the eardrum,
causing it to vibrate. This, in turn, causes three bones in the middle
ear to vibrate, amplifying the sound. Vibrations from the middle ear
set fluid in the inner ear, or cochlea, into motion and a traveling
wave to form along a membrane running down its length. Sensory cells
(called hair cells) sitting atop the membrane "ride the wave" and in
doing so, bump up against an overlying membrane. When this happens,
bristly structures protruding from their tops (called stereocilia)
deflect, or tilt to one side. The tilting of the stereocilia cause
pore-sized channels to open up, ions to rush in, and an electrical
signal to be generated that travels to the brain, a process called
mechanoelectrical transduction."
Is it true that under ordinary hearing conditions the bending of the
stereocilia is caused by direct contact with the tectorial membrane?
Ken
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Kenneth M. Steele, Ph.D. [EMAIL PROTECTED]
<mailto:[EMAIL PROTECTED]>
Department of Psychology http://www.psych.appstate.edu
Appalachian State University
Boone, NC 28608
USA
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Hugh Foley, Ph.D.
Department of Psychology
Skidmore College
815 N. Broadway
Saratoga Springs, NY 12866
518-580-5308
[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>
http://www.skidmore.edu/~hfoley/
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