Effect of Spectrally and Temporally Modulated Maskers on Speech perception in Listeners with Auditory Dys-Synchrony, Cochlear Hearing Loss and Normal Hearing

Abstract

The present study aimed at assessing the speech recognition performance in individuals with auditory dys synchrony (AD), cochlear hearing loss and normal hearing in the presence of spectrally and temporally modulated maskers at 0 dB and JO dB SNR and to obscene which clinical group would take greater advantage of spectral and/or temporal dips to understand speech. Number of words correctly identified within each sentence was calculated in the presence of each of the modulated (spectrally modulated noise with 4 ERB gaps, spectrally modulated noise with 2 ERB gaps and temporally modulated noise) and un modulated (speech shaped steady state noise) maskers at both SNRs in 10 individuals with AD, 13 individuals with cochlear hearing loss and 20 individuals with normal hearing sensitivity. All three groups performed poorer at 0 dB SNR than at 10 dB SNR and in the presence of un modulated than modulated maskers. The AD group performed significantly poorer under temporally modulated noise at both the SNRs, while they showed better performance when masker was spectrally modulated. This could be attributed to the excessive masking in them due to smearing of the temporal wave form. The Cochlear hearing loss group did not benefit from 2 ERB gap spectral modulation. and temporal modulation of noise. The AD group performed significantly poorer compared to the other two groups on. all conditions due to their affected temporal resolution, while this group also showed significant release from masking for spectrally modulated maskers compared to the other groups.