“…In fact, however, there is evidence that a 'second filter' is interposed between basilar membrane displacement, on the one hand, and inner hair cell depolarization or neural excitation, on the other. Such a high-pass filter is evident in the AC receptor potentials of inner hair cells, which at low frequencies (< 500 Hz or so) are proportional to, and in phase with, basilar membrane velocity (Sellick and Russell, 1980;Nuttall et al, 1981;Dallos and Santos-Sacchi, 1983;Russell and Sellick, 1983). We suggest that some form of high-pass filtering extends to relatively high frequencies, perhaps CF, thus permitting suppression to be induced by non-excitatory low-frequency tones (Ruggero et al, , p. 1096Cooper, 1996, pp.…”