Intelligibility of Speech Produced by Children with Hearing Loss: Conventional Amplification versus Nonlinear Frequency Compression in Hearing Aids
- *Corresponding Author:
- Vicky W. Zhang
Pediatric Research Audiologist, National Acoustic Laboratories
Australian Hearing Hub, 16 University Avenue
Macquarie University, Sydney NSW 2109, Australia
Tel: +61 2 9850 7111
E-mail: [email protected]
Received date: May 15, 2015; Accepted date: June 05, 2015; Published date: June 12, 2015
Citation: Ching TYC, Rattanasone NX, Macdonald G, Zhang VW, Button L, et al. (2015) Intelligibility of Speech Produced by Children with Hearing Loss: Conventional Amplification versus Nonlinear Frequency Compression in Hearing Aids. Commun Disord Deaf Stud Hearing Aids 3:135. doi: 10.4172/2375-4427.1000135
Copyright: © 2015 Ching TYC, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Objective: This study aimed to 1) investigate the influence of nonlinear frequency compression (NLFC) in hearing aids on intelligibility of speech produced by children with hearing loss; and 2) examine whether clinicians’ or parents’ judgments might be correlated with those of inexperienced listeners.
Methods: Twenty-seven adult listeners with normal hearing who reported no experience listening to speech produced by people with hearing loss were asked to judge the intelligibility of speech samples of eight hearingimpaired children under four aided conditions. Also, the parents and the clinicians who provided services to the children provided ratings. The children were enrolled in a four-period multi-site trial that was aimed to compare the effects of conventional processing with NLFC in hearing aids on children’s performance. In that study, the children were familiarized with each of four hearing-aid setting for at least six weeks before they were evaluated using a range of tests, including the production of 20 sentences. The current study used the recorded sentences as stimuli for intelligibility judgments. Each listener heard sentences produced by two child-talkers, 40 from each talker. The stimuli were presented to listeners at 65 dB SPL via headphones. Four child-talkers received ratings from eight listeners and four from seven listeners.
Results: Group-level results indicate that speech intelligibility was rated to be better by inexperienced listeners when children used NLFC than when they did not. Three child-talkers showed a significant advantage with NLFC activation. These results are consistent with the estimated audible bandwidth of hearing aids for individual talkers. Significant positive correlations for intelligibility ratings between inexperienced listeners and clinicians were found, but neither correlated with ratings from parents.
Conclusions: The use of NLFC improved intelligibility of speech produced by children, on average, as rated by inexperienced listeners. Clinicians’ judgment of children’s speech production is a clinically viable tool for evaluating the effectiveness of amplification for children.