-
what is the threshold
threshold for any stimulus is the lowest quantity that elicits a certain response
-
what is the history of the newborn screening
- 1950s=hit a cowbell over the infants head
- 1960s=warble tone at 3000 hz
- crib-o-gram=motion sensing device (record babies movement when sound in the nursery
- aud brainstem response=abr
- oae screening
-
what is used when testing children
- headphones, inserts
- bone conduction
- sound field (booth)
-
air conduction
- when possible test using insert or headphones
- allows thresh to be obtained for each ear (bi or unilateral loss)
- gives most accurate assessment of hearing levels
-
what is the purpose of conducting bone conduction
- to determine patients sensorineural sensitivity
- bone conduction placement
- -mastoid process (have to find the sweet spot)
- -forehead
-
sound field testing
- stimulus presented through loud speakers
- freq modulated sounds (warble tone)
- difficulty knowing which ear is responding (better ear thresh were obtained at ____(not sure which ear is responding))
- very sensitive to ambient noise
-
as the system matures what happens to recognizing sound
db goes down
-
behavioral testing
- 5 to 7 months of age
- signal can also be speech, white noise or warble tone
- usually looking for head trun
- usually use some type of visual response as a reward
- if child can not use head turn look for changes in behavior
- -crying when tone present
- -continuation or stopping of bottle feeding
-
conditioned orientating response or visual reinforced audiometry
- signal can also be speech, narrow band or warble tone
- visual stimulus is presented after appropriate head turn response
- delays habituation to tone presentations
- preferable to have two audiologists for testing or us an assistant
-
play audiometry
- used with children above 2 years of age
- child makes a conditioned response (dropping a peg) when a tone is presented
- best accepted method-serves as
- -visible response for audiologist
- -reinforcement for child
- child is not allowed ot play if inappropriate response is made
- child is first trained to make a conditioned response
- followed by threshold seeking period
- use with up to 7 year olds
|
|
