Intelligibility and clarity of clear and conversational speech by children with implants and hearing aids

Abstract

Studies of clear versus conversational speech have shown perceptual and acoustic differences. The basic premise is that the speaker understands the direction to speak more clearly, and translates the direction to speech motor acts. Children with hearing losses receive intervention during which they are instructed to use their best speech. The purpose of this study was to determine: (1) whether hearing-impaired children’s intelligibility changed with directions to use better speech, and (2) whether these children’s speech was judged to be clearer when they had intended to produce clear speech. There were two groups of speakers: 14 deaf children with cochlear implants and 7 hard-of-hearing children with hearing aids. Each produced ten short sentences using typical speech, better speech, and best speech. All sentences were presented to a total of 189 adult listeners with normal hearing who wrote down what they heard. Hard-of-hearing children had average speech intelligibility of 98%; those with implants averaged 66%. Both groups had very small increases across conditions. All sentences in three speech conditions were presented in a paired-comparison task to ten additional listeners. Results of clarity judgments will be discussed in relation to the relatively small changes in speech intelligibility. [Research supported by NIH.]