Two-tone suppression in a cochlear model

Author

Kates, James M.

Author_Institution

Center for Res. in Speech & Hearing Sci., City Univ. of New York, NY, USA

Volume

3

Issue

5

fYear

1995

fDate

9/1/1995 12:00:00 AM

Firstpage

396

Lastpage

406

Abstract

Two-tone rate suppression is a nonlinear property of the cochlea in which the total neural firing rate in the region most sensitive to a probe tone is reduced by the addition of a second (suppressor) tone at a different frequency. A cochlear model featuring a cascade of adaptive-Q filter sections was investigated to determine its ability to reproduce two-tone suppression. It was found that the adaptive-Q filter sections are adequate to reproduce two-tone suppression when the suppressor is located higher in frequency than the probe tone but are not adequate to reproduce suppression for a suppressor lower in frequency than the probe. A modification to the cochlear model, in which the output signal level is adjusted in response to the estimated peak signal levels in the regions of the cochlear filter tip and tail, was much more accurate in reproducing two-tone suppression behavior. A speech example is also presented, and the implications of two-tone suppression in applications of the cochlear model are discussed

Keywords

acoustic signal processing; adaptive filters; audio signals; cascade networks; ear; hearing; interference suppression; speech processing; adaptive-Q filter sections; cascade; cochlear filter tail; cochlear filter tip; cochlear model; estimated peak signal levels; nonlinear property; probe tone; speech; total neural firing rate; two-tone suppression; Adaptive filters; Auditory system; Delay; Frequency synchronization; Probes; Psychology; Shape; Speech coding; Tail; Transmission lines;

fLanguage

English

Journal_Title

Speech and Audio Processing, IEEE Transactions on

Publisher

ieee

ISSN

1063-6676

Type

jour

DOI

10.1109/89.466656

Filename

466656