Ronald Blue wrote:
>> Would some one in the audiology group please respond to
> Stephen Black question.... This topic has been discussed before.
> So I know this is an interesting question to the group.
> Ron Blue
> From: daemon at net.bio.net on behalf of Stephen Black
> Sent: Thursday, May 15, 1997 4:36 PM
> To: neur-sci at net.bio.net> Subject: More on "How does a hearing aid help?"
Expanding on "current theory," if my understanding is correct -- and I
am open to being corrected by any neurophysiologists out there -- the
outer rows of hair cells fine tune the inner rows, and increase the
sensitivity of the entire inner ear in their specific frequency region,
giving the inner row the ability to detect soft sounds, in addition to
the moderate and loud sounds they can detect on their own. Thus a total
loss of outer hair cells and no loss to inner hair cells in a particular
frequency region will produce a mild to moderate senori loss in that
region. A hearing aid will give enough amplification to soft sounds to
allow the inner hair cells to respond to them. A hearing aid will also
stimulate adjacent hair cells, and since the brain attached to the
damaged inner ear is accustomed to interpreting "incorrect" information,
the additional acoustic information can be re-interpreted correctly.
Discordant damage between outer and inner hair cells is probably the
basis for about 80% of tinnitus cases as well.
Robert. J. Olsson (rjolsson at earinfo.com)