When your audiologist tests your hearing the results will be plotted on a graph called an audiogram. If you’ve never seen an audiogram or been told how to read one, it can be a bit confusing. Let’s take a look at how to read an audiogram and some real life examples.
The audiogram reads in frequency (pitch) across the top or horizontal axis and it reads in decibels (loudness) down the side or vertical axis. Just like a piano’s keyboard, the pitches are low on the left side (125 or 250 Hz), and they gradually climb to higher pitches on the right side (8000 Hz). The loudness scale goes from very soft sounds at the top (-10 or 0 dB) to very loud sounds at the bottom (110 dB). It is important to remember that 0 dB does not mean that there is no sound at all. It means the softest sound that a person with normal hearing ability would be able to detect at least 50% of the time. Normal conversation speech is about 45 dB.
The audiogram shows the minimum volume at which a person can detect a tone played at the particular frequency. “X” is used for the left ear and “O” represents the right ear. Sometimes the audiogram will also show bracket symbols “[” and “]”. These represent the scores based on bone conduction tests.
Let’s take a look at a few sample audiograms.
The first audiogram is for Annie who is 75 years old and a grandmother to 8 wonderful grandchildren. Annie has a moderate hearing loss that is the result from degeneration of the hair cells within the ear due to the normal aging process. Before she was fitted with hearing aids, Annie always found conversations with her younger grandchildren to be particularly difficult – especially within a noisy situation. She also found telephone conversations difficult and noisy restaurants were the “band of her existence.” Annie will be fit with new open fit hearing aids which will help raise the frequencies between 2000 and 8000. Annie is expected to do very well and should not have a problem hearing her grandchildren.
Bill has been a construction worker for over 40 years and admits to rarely using ear protection for most of that time. His sharply sloping loss in the higher frequencies can largely be put down to noise induced hearing loss produced by electrical saws and other equipment that he has used in his job. Bill will be fitted with open-fit hearing aids and will benefit from Bluetooth technology on the job pairing his phone with his hearing aids.
David is currently suffering from a hearing loss due to a nasty illness that has led to fluid in his middle ear. He is not hearing very well at the moment and his ears are hurting and “feel tight on the inside”. This infection is causing a problem with the passing of sound through his middle ear, as can be seen by the normal hearing scores he has from his bone conduction tests, represented by the “[” and “]”, but impaired air conduction results. After David sees his doctor to help drain his ears, David’s hearing will return to normal.