How Many Waves Propagate in the Cochlea?

摘要

It is commonly assumed that only a single type of wave gives rise to almost all of the normal measured properties of the cochlea. It is shown here that any form of longitudinal coupling, in addition to 1D fluid coupling, will give rise to additional types of waves, which may or may nor propagate depending on their wavenumber and may or may not play a role in cochlear function depending on whether they are significantly excited. The properties of these waves can be calculated analytically for simple extensions of the standard model, or using the "wave finite element" method for more complicated numerical models. The wave parameters calculated by these methods can be used to decompose the behavior of a fully coupled cochlear model in terms of individual wave amplitudes and thus quantify the importance of other wave types.