Anyone with more than 70db of loss or with very rapid changes in threshold losses (steep curve) of their audiogram, most likely has some dead area’s. A dead region is defined as a part of the cochlea that does not evoke any true response. Often these dead or severely degenerated area’s will give a false response to high levels of pure tone testing by vibrating adjacent good area’s.
Professionals should use a masking system called the TEN test to find these dead spots.
Anyone at home can get a pretty good indication of their dead spots (if any) by using the following method using a PC and its speakers:
First download a audio program that has the piano scale like:
Then aided and un-aided listen carefully to each piano note; If you have perfect normal hearing you would hear each successive tone as a sustained musical note for about 2 seconds…and clicking on the next piano tone should result in a continuously rising (or falling) of pitch. If you click on a note and just get a thud or the pitch does not change then in all likelihood you have a dead or severely degenerated region at that musical frequency.
Note: The customary pure tone threshold of hearing test (Audiogram) given by a professional will not detect dead area’s in most cases. Many times the professional will mistakenly program the aids boosting the gain at the dead area. This usually results in overloading and poorer speech comprehension. Ed