Re: Selective numbing (was: Re: Why is high high?)

[Andrew Vermiglio <avermiglio@xxxxxxx>]

Eliot Handelman wrote:

Andy, during and after exposure to high-intensity high sounds
my frequency response was noticably numbed. My own voice souded
different to me afterwards, as though my hearing had been selectively
anesthetized,
though after a few minutes things returned to
normal. I wonder whether anyone here knows of relevant studies
involving selected numbing of this sort? My thought is that the
numbing effect is a protective adaptation, which fails to come into
play with loud bass sounds with a rich spectrum, such as is normally
found in rock music, which, I think, does cause
hearing loss. I don't go to rock concerts regularly but when I have I've
never
noticed the special selective numbing effect found in the other music.

Eliot, if I am understanding you correctly, the "selective numbing" is also
called a temporary threshold shift.  Basically this means that the softest
sounds that you could hear before the noise exposure have become inaudible.
If your ability to hear these soft sounds is not restored then it is called
a permanent threshold shift.  Please note that this is not a protective
adaptation.  It is an indication of auditory system damage.  High levels of
sound exposure can result in damage to the cochlea.  This damage may be
perceived in two ways; 1) a hearing threshold shift and 2) a decreased
ability to understand speech in noisy environments such as a crowded
restaurant.  There are several articles and books which cover this topic.
You may want to look under the general topic of hearing conservation.
Additionally, if you notice a change in your hearing you should be tested by
an audiologist.

Regards,

Andy Vermiglio

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