Pure Tone & Speech Audiometry Flashcards
(20 cards)
What is pure tone audiometry?
This is a hearing test carried out on individuals who you suspect have a hearing loss.
What is speech audiometry?
This is a procedure where you use words instead of tones as the test stimulus to assess the clarity in someone’s hearing.
What is cross hearing?
This is when you have to increase the sound going into one ear and when that sound reaches a certain loudness, that sound is picked up by the other ear.
What technique can you use to stop cross hearing from happening?
Masking
What is masking?
Masking prevents the non-test ear from detecting a signal so the ear that is being tested is the only one.
What does the 0 line represent on an audiogram?
This is a real sound and represents the average hearing threshold for young, healthy ears.
What is the aim of pure tone audiometry?
This aims to identify the quietest sounds a person can hear to establish their hearing threshold.
What shapes are used to represent the right ear and left ear on audiograms?
Right ear is circles.
Left ear is crosses.
Why do you carry out bone conduction audiometry?
This is used to identify the type of hearing loss an individual has e.g. conductive or sensori-neural.
What is bone conduction audiometry?
BC sends the sound straight through the skull to the cochlea, bypassing the outer and middle ear.
What four frequencies are tested in bone conduction?
1,000Hz, 2,000Hz, 4,000Hz and 500Hz.
What shape is an unmasked bone conduction threshold represented by?
Triangle
If masking has been used on the right ear, what symbol represents this?
The bracket symbol [
If masking has been used on the left ear, what symbol represents this?
The bracket symbol ]
What are the 5 reasons for performing speech audiometry?
- Gain measurement of threshold for speech - usually the quietest level of which they get 50% of words correct.
- To know how many words they get correct at their comfortable listening level (quantify their speech recognition ability).
- To examine the impact of background noise on speech perception in normal and impaired ears.
- Hearing aid fitting - identify their best speech recognition ability with different hearing aids.
- To identify differential diagnoses between sensory and neural hearing losses.
What do the results for a conductive hearing loss look like for speech audiometry?
Because a conductive hearing loss means someone has a blockage of sound travelling to their cochlea, this means you will have to increase the decibels before they get all the words correct.
If we increase the presentation level by the amount of their conductive loss, in this example about 30dB conductive loss, they will continue to get all the words right and so the curve is just pushed to the right side by the amount of their conductive loss (30dB).
What do the results for a sensory hearing loss look like for speech audiometry?
To some extent, people with sensory losses lose the ability to hear quiet sounds but also experience reduced ability of hearing clarity because of reduced OHCs so their hearing becomes slightly muffled.
For number 3 even at their most comfortable listening level (80-90dB), they never get more than 60-65% of the words correct. So no matter how loud you make the presentation level, they’re never going to score 100%.
What do the results for a neural hearing loss look like for speech audiometry?
Number 3 has such distorted speech that even when you increase the sound amplitude, they never score more than 10% of the words right because their speech discrimination is so distorted.
Number 1 reaches their comfortable hearing level and then the sound amplitude is increased which effectively puts too much strain on the damaged auditory nerve which tires easily because it’s damaged so their performance suffers as the nerve cannot cope with all the speech information so their speech discrimination becomes distorted as well.
