Auditory filter bandwidths were measured using nonsimultaneous masking, as a function of signal level between 10 and 35 dB SL for signal frequencies of 1, 2, 4, and 6 kHz. The brief sinusoidal signal was presented in a temporal gap within a spectrally notched noise. Two groups of normal-hearing subjects were tested, one using a fixed masker level and adaptively varying signal level, the other using a fixed signal level and adaptively varying masker level. In both cases, auditory filters were derived by assuming a constant filter shape for a given signal level. The filter parameters derived from the two paradigms were not significantly different. At 1 kHz, the equivalent rectangular bandwidth (ERB) decreased as the signal level increased from 10 to 20 dB SL, after which it remained roughly constant. In contrast, at 6 kHz, the ERB increased consistently with signal levels from 10 to 35 dB SL. The results at 2 and 4 kHz were intermediate, showing no consistent change in ERB with signal level. Overall, the results suggest changes in the level dependence of the auditory filters at frequencies above 1 kHz that are not currently incorporated in models of human auditory filter tuning.
|Original language||English (US)|
|Number of pages||10|
|Journal||Journal of the Acoustical Society of America|
|State||Published - Jan 2006|
Bibliographical noteFunding Information:
This work was supported by the National Institutes of Health (R01 DC 03909). We thank Christophe Micheyl, Xuedong Zhang, and Chris Shera for helpful comments on previous versions of this manuscript and Bertrand Delgutte for useful discussions. Brian Moore, Richard Baker, an anonymous reviewer, and the associate editor, Armin Kohlrausch, also provided many helpful comments during the review process.