What is overmasking?

Overmasking occurs when the masking noise presented to one ear (the non-test ear, or NTE) is so intense that it crosses over and affects the test ear (TE). This excessive masking can generate false hearing thresholds, meaning the results obtained during an audiometric evaluation do not accurately reflect the true auditory ability of the test ear. The threshold may appear to be worse than it is, leading to potential misdiagnoses or inappropriate treatment recommendations.

In clinical practice, proper masking is paramount. When the masking level is excessive, it inadvertently stimulates the TE, causing it to respond to the masking rather than the actual test signal. This misrepresentation can seriously compromise the reliability of the hearing assessment, making it crucial for hearing aid specialists to understand the concept of overmasking to ensure accurate testing and appropriate audiological intervention.