If IA is increased, how is the masking plateau affected?

When the interaural attenuation (IA) is increased, the masking plateau becomes wider. Interaural attenuation refers to the reduction of sound intensity as it travels from one ear to the other. A higher IA indicates that there is a greater difference in the sound level perceived by the ears.

In clinical practice, specifically in audiology and hearing aid dispensing, a wider masking plateau implies a more effective separation of the sound signals in the ears during hearing assessments. This allows for more reliable determination of hearing thresholds, as the amount of noise needed to mask the non-test ear effectively increases. Therefore, as IA increases, the ability to maintain a consistent masking level across various pitches and loudness levels also improves, leading to a wider plateau.

This is crucial when performing audiometric testing, where accurate results depend on effective masking to ensure that the test ear's sounds are not influenced by the non-test ear. Hence, the relationship between increased IA and a wider masking plateau is essential for successful hearing assessments and interventions.