Figure 4.

BM transfer functions computed at 64 equispaced locations in two different models. A, Transfer functions in a “smooth” model without micromechanical irregularity. The CFs span the range 7–9 kHz, representing a distance of ∼1 mm along the chinchilla BM; frequency responses were computed at intervals approximately corresponding to the width of two inner hair cells. B, Transfer functions computed at the same spatial locations as in A but using an “irregular” model in which small, micromechanical irregularities and an impedance mismatch at the stapes give rise to multiple internal reflection.