Knaster - Interacoustics Affinity 2.0 Additional Information

2.0
Affinity Additional Information
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1.7.11 Knaster

Knaster is a speech in noise training tool. Modified 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
affect the auditory pathways and centres. After applying the noise for a certain amount of time (in seconds)
discrimination problems should disappear temporarily.
The training should be performed subsequent to 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 for a few 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 for the second time it is believed to
be easier for the patient to perceive it. When succeeding in repeating the word correctly the patient should
be made aware of the difference 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 (Appendix 2).
Required Items:
•
2
The Affinity hardware
•
Licensed AC440 Audiometry module within your Affinity
•
Headphones
Test Procedure:
In order to perform the Knaster test you need to know the level of maximum speech understanding. The test
should therefore be performed subsequent to the speech audiometry which will provide you with this
information. Do the Speech Audiometry as described in section 1.6.5.5.
1) Open the AC440 and enter the Knaster screen by selecting Menu | Tests | Knaster
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Knaster is only available on the Affinity
2.0 2.0
/Equinox
2.0
hardware with Knaster functionality
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