What is an Audiogram?
An Audiogram is the universal way to represent someone’s hearing in the form of letters and symbols.
An O represents the right ear while an X represents the left ear. These Xs and Os represent air conduction thresholds. In other words, they represent the entire hearing mechanism from the ear canal, through the ear drum, through the ossicles (bones in the middle ear), cochlea (the organ of hearing), all the way up to the auditory nerve.
Brackets that are seen on a hearing test may look like [ if representing the right ear and ] if representing the left ear or ^ if representing both ears. These brackets represent bone conduction thresholds. These bone conduction thresholds bypass the ear canal, eardrum, and ossicles and directly stimulate the cochlea (the organ of hearing) and the auditory nerve. By comparing air conduction and bone conduction thresholds, we are able to determine the type of hearing loss that someone has.
There are three types of hearing loss:
- sensorineural (air and bone conduction thresholds are the same)
- conductive hearing loss (bone conduction scores are within normal limits but there is a gap between bone conduction and air conduction thresholds)
- mixed hearing loss meaning there is both sensorineural AND conductive hearing loss present.
Audiologists describe hearing loss in terms of type (sensorineural, conductive, or mixed) and also in terms of severity. A mild hearing loss is from 25-40 dB, a moderate hearing loss is from 41 to 55 dB, and moderately severe hearing loss is from 56-70 dB, a severe hearing loss is from 70-90 dB and a profound hearing loss is anything greater than 90 dB.
When looking at an audiogram, the top represents the frequency or pitch. Frequency is measured in Hertz (Hz). Think of this as the keys on the piano from low pitch like male voices to high pitch like female voices.
The side represents intensity or loudness. Loudness is measured in decibels (dB). Soft sounds like a whisper are at the top and the bottom represents loud sounds like a jackhammer. As the symbols on your audiogram start to move further down on the chart, hearing loss is present.
You may see speech scores on your audiogram as well. The two most common types of speech tests are SRT (speech reception threshold) and WRS (word recognition score). An SRT score is simple the softest level that you can detect words called spondees (two syllable words with equal emphasis on each syllable). For example, hotdog, baseball, cowboy, playground. WRS is obtained by presenting 25 or 50 words at a level we know a patient can hear and recording the percentage. This score helps determine candidacy for hearing aids with 100% being ideal. If a patient has a WRS in the 20s or 30s they may need more than just a hearing aid in order for them to communicate effectively.
It is important to have your hearing checked by an Audiologist. It is recommended that people aged:
- 18-45 years have their hearing checked every 5 years
- 45-65 years have their hearing checked ever 3 years
- 65+ years have their hearing checked every 2 years
At NDBC Hearing Clinic, we offer free hearing aid evaluation where we
- Assess your lifestyle. Finding what hearing aids will fit you best.
- Trial hearing aids that are programmed to your hearing needs
- Further diagnostic testing to ensure proper programming of your hearing aids.
- Answer any other questions you may have.