"Put a plug in it"

[Sarah Fox]

Hi Elwood,

> This is "for what it's worth":
> Several years ago I quit drinking caffeinated coffee since I found that
piano sounds were becoming loud and bright.  Started drinking decaffeinated
coffee and problem went away.

Fascinating!

Yes, that makes sense.  The ear is an active device.  You have two groupings
of hair cells (vibration receptors) on your basilar membrane (the
vibration-sensing organ in your inner ear).  The inner hair cells are what
actually sense the sound.  The outer hair cells are mechanically linked to
the inner hair cells via an overlying flap called the tectorial membrane.
When the outer hair cells are vibrated, they vibrate back.  (This is a
positive feedback mechanism.)  In other words, the outer hair cells make a
weak vibration stronger.  They are jazzed up, I believe, with caffeine,
which could make the ear hyperresponsive.

What you experienced was more than a perception.  It was physical.  Because
your ear is no longer *mechanically* hyperresponsive, there would be less
potential for damage from loud sounds.

Peace,
Sarah