What is the interaural attenuation (IA) value for bone conduction?

The interaural attenuation (IA) value for bone conduction is 0 dB, which indicates that there is no reduction in sound intensity when transmitted through the bones of the skull from one ear to the other. This means that when sound is delivered via bone conduction, it can stimulate both cochleae simultaneously, regardless of the ear receiving the stimulus. As a result, any sound heard may come from either the stimulated ear or the non-stimulated ear, making it crucial for clinicians to consider this factor when interpreting hearing test results.

In contrast, the other values, such as 15 dB, 70 dB, and 40 dB, are specific to air conduction and reflect varying levels of sound attenuation that occur when sound travels from one ear to the other via air conduction pathways. These levels indicate how much sound may be lost en route between the presented ear and the opposite ear, depending on the method of transmission, but they do not apply to bone conduction where the sound is conducted through the bone of the skull directly to the inner ear.