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Re: New Scientist Question

Laszlo Toth wrote:

> A couple of weeks ago I had a nice little ringing tinnitus in my right
> ear. (Luckily it went away after a week, just when I started to get
> worried about going crazy).
> So, I observed that the loudness of my "built-in-sine-wave" increased when
> yawning (no change in pitch, however). My physician said the the cause
> of tinnitus is usually some inner ear or auditory nerve injury. If so,
> how could the loudness be altered by a middle-ear "operation" (yawning)?
> Or maybe yawning made all the other background sounds softer and thus
> tinnitus seemed to get louder?

Very interesting account.

1) What you had most probably was not tinnitus, but a temporary increase in
the loudness of a spontaneous otoacoustic emission (SOAE). Tinnitus rarely
comes as a sine wave, but SOAEs always do. Many of us experience a temporary
audibility of an SOAE that usually lasts only a few seconds. But it can also
stay for years. In some cases SOAEs can become so strong that they can even
be heard by a second person getting close to the emitting ear. Emitters are
clusters of outer hair cells (OHC) in the cochlea.

2) It is well known that both pitch and loudness of SOAEs can be influenced
by changes during the reverse transmission of sound in the middle ear.
Middle ear air-pressure changes (as in yawning) can also have an impact on
cochlear mechanics and thus influence the generation or transmission of

3) According to current knowledge, most cases of tinnitus are based on
abnormal activity in the auditory cortex, which developed in the aftermath
of an inner ear pathology, usually noise-induced hearing loss.


Martin Braun
Neuroscience of Music
Gansbyn 14
S-671 95 Klässbol