The musician’s worst nightmare and Hallowell Davis

Some would think that hearing loss is the musician’s worst nightmare, and some would think that it is tinnitus, but the musician’s greatest fear is losing their ability to perceive pitch.  This is related to hearing but isn’t the first thing that audiologists typically think about when they assess a musician.

To understand a musicians’ fear of losing their ability to perceive pitch we need to go back to an American army experiment from 1948 where one of the founders of our field (Dr. Hallowell Davis) convinced a group of US servicemen to sacrifice one of their ears for their country.

Dr. Davis published his findings in 1948, and again in a different form in 1950.  I guess that researchers like to publish their data twice in case someone missed it the first time.  I guess that researchers like to publish their data twice in case someone missed it the first time…..

Essentially Dr. Davis exposed one ear of the servicemen to very intense and prolonged noise while protecting the other ear as much as possible.  This created a hearing loss in one ear only so that each person could use their normal ear as a judgement standard against the damaged side.  I am sure that this type of study would never pass a modern day ethics board review!

He gave them access to two knobs- one that adjusted frequency and the other that adjusted intensity and a pure tone of a known frequency was played to the normal ear.  The servicemen had to adjust the knobs to match what they heard in their damaged ear.

As can be guessed, in the region where there was still minimal damage in the ear, both ears performed similarly- as the test frequency went up on one side, the frequency knob was adjusted up equally on the damaged side.  However, as the region of damage was approached (I recall it being about 3000 Hz, the G below the top note on the piano keyboard) exciting things began to happen.

As the frequency was increased in the good ear, the servicemen increased the intensity to match it but not the frequency.  As the test frequency was increased, they perceived it as increase in loudness, but not as an increase in pitch.  The damaged ear then matched the frequency to a lower frequency presented in the good ear (albeit at a slightly higher level).  In musical terms, the damaged ear was flat.

When musicians see me clinically and comment that certain tones are flat, I feel relieved.  This suggests that the damage is “merely” cochlear and not more central.  If the musician feels that their worse ear is sharp relative to either their better ear or what their normal tuning is, then this is not suggestive of a cochlear disorder- perhaps a central one which is far more difficult to remediate.

I have a client that I saw only about a month ago who has this problem.  On my piano in my office (and yes, I have a piano in my office, doesn’t everyone?) as he slowly played the notes I asked him to tell me when two adjacent notes were essentially the same.  This happened for every octave of C with the B below it.  Middle C [262 Hz] sounded very similar to the white note (B[247 Hz]) just below it.  And this was true to the octave above it… C[524 Hz] sounded the same as B[494 Hz], and so on.  This person had a flat 50 dB sensori-neural hearing loss so this broadband distortion of pitch wasn’t surprising.  If the person had had only a high frequency loss, I am sure that I would have found the same thing for only the damaged high frequency region.

So, what can be done?

He was fit with a hearing aid with a broadband response for speech (in program 1) and a “notched filter” response in program 2 for music.  Essentially I notched out every B and C region in every octave and in most cases, provided him with some attenuation at these frequencies.

The result wasn’t perfect but he did note that he could no longer hear the pitch distortion that had so bothered him in the past.

About Marshall Chasin

Marshall Chasin, AuD, is a clinical and research audiologist who has a special interest in the prevention of hearing loss for musicians, as well as the treatment of those who have hearing loss. I have other special interests such as clarinet and karate, but those may come out in the blog over time.