See also:Test Type Working Principles
A§E (pronounced [eis] like the play card ace) is a set of psycho-acoustical tests to be used by the professional audiologist. It is conceived to test hearing impaired children and adults who typically have a conventional hearing aid, cochlear implant or other device. Whereas most tests are speech- and language independent and supraliminal (above-threshold), this type of test is not.
It is recommended to use A§E with a conventional audiometer. No additional equipment is required. A§E can also run with one of Audiqueen’s audio solutions, such as an amplifier and loudspeakers, SoundC or even with nothing else than a set of good quality multimedia loudspeakers.
All test results are presented in comprehensive tabular or graphical charts. They can be printed, saved and exported. Remarks can be added to each test item.
A§E comprises 6 modules:
- The “classical” A§E tests based on speech sounds used in:
- a two-choice (yes/no) phoneme detection test;
- a phoneme discrimination test in an oddity paradigm;
- a closed set phoneme identification test using a picture-pointing response;
These tests aim to assess the coding of spectral information.
All sounds that are used are phonemes that are common in many languages. All phonemes have equal durations and were rms-balanced in the beginning2, but corrections based on subjective loudness balancing have been made by 30 normal hearing volunteers. For the discrimination and identification tests intensity roving is applied in a range of ±3 dB, meaning that a random gain ranging from -3 dB to +3 dB is applied to a given phoneme when it is presented. This should eliminate the intensity cues that remain after all this equalizing and due to the persisting differences in the temporal profile of different phonemes.
- The intonation tests consisting of:
- The prosody tests: sentence intonation and word stress pattern;
- Three same/different tests with synthetic sounds: harmonic complexes, harmonic intonating sounds and disharmonic intonating sounds
These tests aim to assess the low frequency coding with special interest for the temporal fine structure coding.
They contain low frequency spectral cues, basically differences of the fundamental frequency ΔF0, either alone or in combination with differences of the corresponding harmonics 2F0, 3F0 and 4F0. The reference F0 = 200 Hz for all tests. The presentation level is 70 dB SPL with roving of ±3 dB.
- The loudness scaling test:
This test aims to assess the intensity coding.
It consists of a typical loudness scaling task at 250, 500, 1000, 2000, 4000 and 6000 Hz, assessing the loudness growth function of the (aided) cochlea. The test stimuli are narrow band noises centred at these frequencies and presented at different levels. The results provide useful feed-back for the programming of the hearing device (hearing aid or cochlear implant).
- The localization test:
- The ILD localization test. This test aims to assess the central integration of binaural stimulation with cochlear implants.
- The azimuth localization test: This test aims to assess the azimuthal localization acuity. It is a binaural localization test using SoundC with 5 or 7 speakers. Different stimuli can be used, such as narrow band noise, speech shaped noise, etc.
It is a binaural localization test for which only 2 loudspeakers are required. It is based on interaural level differences (ILD’s) roving around presentation levels of 60 dB SPL. The localization test assesses the localization capacity of the listener, giving an indirect view on the central integration of the binaural signal.
- Audiometry: When connected to a 'supported' audiometer, this module offers a user friendly graphical interface to perform audiometry. When connected to one of Audiqueen’s audio solutions, it offers the same user interface, while the range of presentation levels is reduced due to output limitations of the soundcard used.
- Speech Audiometry: This module offers a wide range of speech audiometric options with words or sentences, in quiet or in different kinds of noise, with manual or adaptive scoring, etc. When connected to a 'supported' audiometer, this module qualifies as ISO compatible speech audiometer. When connected to one of Audiqueen’s audio solutions, it offers the same user interface, while the range of presentation levels is reduced due to output limitations of the soundcard used.
- Binaural Benefit: This is not really a separate module, but rather a script guiding you through 4 speech audiometrical tests executed with the SoundC hardware to assess the benefit of a second aid in addition to a first aid in temrs of head shadow and squelch benefit.
See also: How to perform A§E selftests?