The effects of high‐frequency masking bands on midfrequency frequency discrimination

Abstract

To evaluate the contribution of high‐frequency hearing during frequency discrimination at lower frequencies, an adaptive 4‐IFC pure‐tone frequency discrimination task was performed by two highly practiced normal‐hearing listeners at signal levels from 10 to 80 dB SPL, with and without high‐frequency band‐pass masking noises. The spectra of the high‐frequency masking noises ranged from 1.8 to 2.1 kHz, from 2.8 to 3.1 kHz, and from 4 to 8 kHz. The DLF‐intensity functions, describing DLFs as a function of sensation level, that were obtained in the presence of the high‐frequency masking noises were essentially the same as the DLF‐intensity functions obtained without masking noises. DLF‐intensity functions obtained from one of the two listeners were in close agreement with the results reported by Wier et al. [J. Acoust. Soc. Am. 61, 178–184 (1977)]. The functions from the other listener were similar in form, but exhibited consistently larger DLFs at all sensation levels. No practice effects were found throughout the investigation. [This research supported by NIH research grant NS12125.]