Pure-Tone Octave Masking in Listeners with Sensorineural Hearing Loss

Abstract

Pure-tone octave masking was investigated in 14 listeners with sensorineural hearing loss to examine the hypothesis that the sensorineural ear introduces abnormal harmonic distortion. Thresholds for a test signal at f 2 , masked by a masking signal at f 1 , (where f 2 = 2f 1 ) were obtained as a function of the level of the f 1 masker for four different f 1 frequencies (250, 500, 1000, and 2000 Hz) and two different phase relations between the f 1 and f 2 signals (90° and 270°). Analysis of the data in terms of the absolute level of the f 2 test signal at masked threshold vs the absolute level of the f 1 masking signal leads to the conclusion that these pathological ears do not perform differently from normal ears, except along the dimension of hearing loss. That is, their hearing losses do not add significant distortion to the acoustic signal. Analysis of the data in terms of the sensation level of the f 2 test signal at masked threshold leads to the specious conclusion that the sensorineural ear introduces abnormal distortion.