Friday, July 28, 2017

Suki is Going Deaf

Suki is going deaf. She has not lost all her hearing yet, but when I call her in a normal voice she does not respond. She used to jump up when she heard me get the leash for a walk, but now I have to show it to her. Before she was scared of thunderstorms, but lately she snoozes through all but the loudest rumbles. In the past she got excited when the garage door opened, but nowadays she ignores it. Suki will be 15 years old this October, so such problems are expected. Still, I am sad to see her sink into silence.

I think my hearing is getting worse too, but slowly. My dad uses a hearing aid, and I take after him. I find myself asking “what did you say?” more often than other people do. I decided to test myself using the website http://www.animations.physics.unsw.edu.au/jw/hearing.html. Below I plot my hearing (red dots) as a function of frequency, and compare it to the normal hearing response of a young adult (solid curve) shown in Figure 13.7 of Intermediate Physics for Medicine and Biology. I normalized the two curves so they are equal at 1 kHz.
My hearing appears normal except for an odd deficit around 3000-4000 Hz. Also, I may be missing some high frequencies, but the loss is not dramatic.

I didn’t follow the website’s instructions exactly. I plotted the lowest intensity tone that I could just hear. I don’t trust this test, performed on myself using a website; it is very subjective and the loudness changes in large 3 dB steps. (In case you do not have IPMB handy, Eq. 13.34 indicates that a ten-fold change in intensity corresponds to a step of 10 in decibels.) I would be interested in hearing (get it?....) if you have a similar result using this website.

Age-related hearing loss is called presbycusis. Wikipedia says it is the second most common illness in the elderly, after arthritis. Normally we lose the high frequencies as we age, which has implications for how teenagers choose ringtones.


On the above video, I could hear the 8 kHz ringtone but not the 12 kHz or higher ones. Can you? I am not sure if it is me, my computer, or the video.

I may be losing some hearing, but probably not much. (Perhaps I just don’t pay attention when my wife talks to me.) Suki, however, is in worse shape. She is the world’s best pet, and I intend to give her extra treats to make up for her lack of hearing.

2 comments:

  1. Sorry to read about your dog's hearing! At least it's perhaps soothing not to hear thunderstorms...

    ReplyDelete
    Replies
    1. That is definitely a silver lining!

      Delete