BM displacement (a) magnitude and (b) phase distribution along the cochlear longitudinal direction, plotted as a function of distance from the apex, in response to a 15 kHz tone over a range of intensities from 15 to 60 dB SPL [48] (reprinted from PNAS, 94, Russell and Nilsen, The Location of the Cochlear Amplifier: Spatial Representation of a Single Tone on the Guinea Pig Basilar Membrane, 2660–2664, Copyright (1997) National Academy of Sciences, USA).
