(a–c) BM displacement-level functions in response to
12.5 kHz, 15.5 kHz (CF), and 17.5 kHz tones for different locations
across the width of the BM. The locations are measured from the edge of
the spiral lamina (symbols shown in c). Dashed line
indicates slope of 1. (d–f) BM gain
(nanometers/Pascal) in response to 12.5-kHz, 15.5-kHz (CF), and
17.5-kHz tones as a function of measurement location across the width
of the BM for stimulus levels between 15 and 85 dB SPL (symbols shown
in f). The solid stars represent BM gain of
vibrations measured on the spiral lamina attachment (SLAM) (0.7) and
spiral ligament attachment (SLIG) (1.7) at 95 dB SPL from a postmortem
preparation. (g–i) BM phase as a
function of the stimulus level of 12.5-kHz, 15.5-kHz (CF), and 17.5-kHz
tones for different measuring locations across the width of the BM
(symbols shown in i). (j–l) BM phase in
response to 12.5-kHz, 15.5-kHz (CF), and 17.5-kHz tones as a function
of measurement location across the width of the BM for stimulus levels
between 15–85 dB SPL (symbols shown in l). The solid
stars represent BM phase of vibrations measured on the SLAM and SLIG at
95 dB SPL from a postmortem preparation. The vertical dashed lines
represent the inner SLAM and outer SLIG of the BM. Horizontal bars as
in Fig. 1d; BM width: 190 μm; CAP threshold at CF: 12
dB SPL; 0 dB loss after opening cochlea to expose the BM; measurement
noise floor 0.7 nm. b, e, h, and k are from
Nilsen and Russell (22), with permission from Nature
Neuroscience (Copyright 1999).