A compressive gammachirp auditory filter for both physiological and psychophysical data

A gammachirp auditory filter was developed by Irino and Patterson [J. Acous t. Sec. Am. 101, 413-419 (1997)] to provide a level-dependent version of th e linear, gammatone auditory filter, with which to explain the level-depend ent changes in cochlear filtering observed in psychophysical masking experi ments. In this 'analytical' gammachirp filter, the chirp varied with level and there was no explicit representation of the change in filter gain or co mpression with level. Subsequently, Carney et al. [J. Acoust. Sec. Am. 105, 2384-2391 (1999)] reviewed Carney and Yin's [J. Neurophysiol. 60, 1653-167 7 (1988)] reverse-correlation (revcor) data and showed that the frequency g lide of the chirp does not vary with level in their data. In this article, the architecture of the analytical gammachirp is reviewed with respect to c ochlear physiology and a new form of gammachirp filter is described in whic h the magnitude response, the gain, and the compression vary with level but the chirp does not. This new 'compressive' gammachirp filter is used to fi t the level-dependent revcor data reported by Carney et al. (1999) and the level-dependent masking data reported by Rosen and Baker [Hear. Res. 73, 23 1-243 (1994)]. (C) 2001 Acoustical Society uf America.