Knaster - Interacoustics Affinity 2.0 Additional Information

Test procedure:
1) Open the AC440 and enter the Weber screen by selecting Menu | Tests | Weber
2) Input and Output selections f or channel 1/channel 2 are f ixed Tone and Bone.
3) Place the bone conductor on the patient's f orehead and instruct them to tell you if the tones presented
are heard better to the Right, Left, Centre or if it is Not heard at all.
4) Present a tone at a level of 10 dB above the worst BC threshold using the dB HL Decrease/Increase
buttons or the PC keyboard. You can select whether you want a Tone or Warble stimulus.
5) Await response f rom the patient and click on the corresponding button above the graph.
If the patient hears the tone better in the poorer ear the hearing loss is conductive, and the tone is
heard better in the better ear the hearing loss is sensorineural at the given f requency.
6) During the testing the f requency and intensity can be adjusted manually (see illustration).
7) Save the Weber test by clicking Save

1.7.11 Knaster

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Knaster is a speech in noise training tool. Modif ied speech noise (Knaster Noise) is presented to one or both
ears (binaurally) as this is believed to initiate a state of "alertness" in the sensorineural cells and thereby also
af f ect the auditory pathways and centres. Af ter applying the noise f or a certain amount of time (in seconds)
discrimination problems should disappear temporarily.
The training should be perf ormed af ter doing the speech audiometry since you need to present the Knaster
speech at the point of maximum speech understanding which will be detected in the speech audiometry. The
level the Knaster noise should be presented at is 5 or 10 dB lower than the presented speech material.
The patient is asked to repeat the speech presented. If mistakes between sounds are made the noise is
increased f or a f ew seconds in attempt to "awaken" the sensorineural cells. The noise is then turned down
to its original level and the patient is prompted to try and correct the mistake and the repeat the word again.
If the noise is muted at the same time as the mistaken word is repeated f or the second time it is believed to
be easier f or the patient to perceive it. When succeeding in repeating the word correctly the patient should
be made aware of the dif f erence between the sound they emitted and the correct sound.
If patients undergo half hour Knaster sessions on consecutive or alternating days their discrimination abilities
are believed to improve.
Required items:
The Af f inity 2 hardware
•
Licensed AC440 Audiometry module within your Af f inity
•
• Headphones
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Knaster is only available on the Affinity
D-0004576-Q – 2022/05
Affinity/Equinox2.0 – Additional Information
2.0 2.0
/Equinox
2.0 hardware with Knaster f unctionality
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