Effects of Expanding Envelope Fluctuations on Consonant Perception in Hearing-Impaired Listeners. (May 2018)

• Record Type: Journal Article
• Authors: Wiinberg, Alan; Zaar, Johannes; Dau, Torsten
• Is Part Of: Trends in hearing. Volume 22(2018)
• Publication Date: 2018-05
• Subjects: consonant recognition -- hearing impairment -- hearing instruments -- speech enhancement -- temporal envelope; Hearing aids -- Periodicals; Cochlear implants -- Periodicals; Hearing impaired -- Rehabilitation -- Periodicals; 617.89
• DOI: 10.1177/2331216518775293
• Languages: English
• ISSNs: 2331-2165

Abstract

This study examined the perceptual consequences of three speech enhancement schemes based on multiband nonlinear expansion of temporal envelope fluctuations between 10 and 20 Hz: (a) "idealized" envelope expansion of the speech before the addition of stationary background noise, (b) envelope expansion of the noisy speech, and (c) envelope expansion of only those time-frequency segments of the noisy speech that exhibited signal-to-noise ratios (SNRs) above −10 dB. Linear processing was considered as a reference condition. The performance was evaluated by measuring consonant recognition and consonant confusions in normal-hearing and hearing-impaired listeners using consonant-vowel nonsense syllables presented in background noise. Envelope expansion of the noisy speech showed no significant effect on the overall consonant recognition performance relative to linear processing. In contrast, SNR-based envelope expansion of the noisy speech improved the overall consonant recognition performance equivalent to a 1- to 2-dB improvement in SNR, mainly by improving the recognition of some of the stop consonants. The effect of the SNR-based envelope expansion was similar to the effect of envelope-expanding the clean speech before the addition of noise.