Hear Ye! Since 1998.
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18
Aug 02
Sun

Hearing

I’ve always been mildly deaf since childhood, so I went for a hearing test last week to see if the situation had changed at all. A hearing test is not all that dissimilar in principle to an eyesight test. They stick you into a soundproofed room (even isolated from the air conditioning system), and play you tones through headphones. The tones are played at a variety of frequencies at different levels of volume. You hit a button when you hear a tone. It gets quite deceptive, because at quieter levels, you’re not sure what is a tone and what is your imagination. They also play words and you’re meant to repeat what you hear, or at least, what you think you hear. The last stage of the test involves them sticking probes into your ear to measure middle and inner ear things.

In the tone test, they measure tonal ranges from 500Hz to 8000Hz which is roughly the normal human vocal range. Normal hearing, like 20/20 vision, should allow people to hear down to 20 decibels. I have mild permanent deafness in the upper ranges (2kHz-8kHz) where sounds must be above 40dB for me to hear – note that the decibel scale is logarithmical. Which to me is slightly worrying because a 20dB difference means those frequencies must be 100 times “louder”, or at least 100 times more powerful, for me to hear, than the normal person, unless I have misinterpreted something. Luckily, it’s still categorised as minor loss. In practical terms, that means I sometimes miss high frequency/low volume parts of words such as affricatives (“ch”) and fricatives (“th”, “sh”, “ss”), but context and limited lip reading ability (that the doctor told I have apparently subconsciously developed) fill in the gaps most of the time. It also explained for me why I can never seem to hear people when they whisper to me… it’s because I simply can’t.