International Licensing Examination (ILE) Practice Test

What is usually observed when one ear has normal hearing and the other is unaidable?

1. Binaural fitting is unnecessary

2. CROS fitting is applied

3. Both ears are treated equally

4. Regular hearing aids can be used

The correct answer is: CROS fitting is applied

When one ear has normal hearing and the other is unaidable, a CROS (Contralateral Routing of Signals) fitting is typically applied. This approach is specifically designed for individuals who have profound hearing loss in one ear while maintaining normal hearing in the other. The CROS system involves a microphone that picks up sound from the side with the unaidable ear and transmits it to the hearing ear. This arrangement allows the individual to perceive sounds from their hearing-impaired side without significantly amplifying sounds—which would not be beneficial since that ear cannot use amplification effectively. Consequently, this setup helps the listener gain awareness of sounds coming from both sides, improving their overall hearing experience. In contrast, other options like binaural fitting being unnecessary or treating both ears equally do not apply in this scenario, as they do not address the specific needs created by the disparity in hearing capabilities. Regular hearing aids would not be suitable for the unaidable ear and would not facilitate sound transmission effectively to the ear that can hear. Therefore, the CROS fitting is the correct approach in this circumstance.