title: Detection threshold for sound distortion resulting from noise reduction in normal-hearing and hearing-impaired listeners.
abstract: Hearing-aid noise reduction should reduce background noise, but not disturb the target speech. This objective is difficult because noise reduction suffers from a trade-off between the amount of noise removed and signal distortion. It is unknown if this important trade-off differs between normal-hearing (NH) and hearing-impaired (HI) listeners. This study separated the negative effect of noise reduction (distortion) from the positive effect (reduction of noise) to allow the measurement of the detection threshold for noise-reduction (NR) distortion. Twelve NH subjects and 12 subjects with mild to moderate sensorineural hearing loss participated in this study. The detection thresholds for distortion were determined using an adaptive procedure with a three-interval, two-alternative forced-choice paradigm. Different levels of distortion were obtained by changing the maximum amount of noise reduction. Participants were also asked to indicate their preferred NR strength. The detection threshold for overall distortion was higher for HI subjects than for NH subjects, suggesting that stronger noise reduction can be applied for HI listeners without affecting the perceived sound quality. However, the preferred NR strength of HI listeners was closer to their individual detection threshold for distortion than in NH listeners. This implies that HI listeners tolerate fewer audible distortions than NH listeners.
authors.affiliation: Academic Medical Center, Clinical and Experimental Audiology, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
authors.forename: Inge
authors.initials: I
authors.lastname: Brons
authors.affiliation: Academic Medical Center, Clinical and Experimental Audiology, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
authors.forename: Wouter A
authors.initials: WA
authors.lastname: Dreschler
authors.affiliation: Academic Medical Center, Clinical and Experimental Audiology, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
authors.forename: Rolph
authors.initials: R
authors.lastname: Houben
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000368:Aged; D001302:Audiometry, Speech; D001309:Auditory Threshold; D016022:Case-Control Studies; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000523:psychology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009622:Noise / Q000009:adverse effects*; D010470:Perceptual Masking; D019986:Persons with Hearing Disabilities / Q000523:psychology*; D011571:Psychoacoustics; D017603:Signal Detection, Psychological; D013018:Sound Spectrography; D013065:Speech Intelligibility; D013067:Speech Perception; D013997:Time Factors; D055815:Young Adult