Author: Kim Zimmerman

Publisher: National Library of Canada = Bibliothèque nationale du Canada

Published: 1998

Total Pages: 143

ISBN-13: 9780612307452

This study investigated the effect of Nucleus and Clarion multichannel cochlear implant use on the speech production of adults with a severe to profound hearing impairment. Specifically, this experiment was designed to ascertain the impact of cochlear implant use on the acoustical characteristics of speech including first vowel formant frequency and second vowel formant frequency. Ten monosyllabic stimuli were used to collect speech samples. The acoustic samples were then analyzed using the CSpeech software package. The data for each subject were assessed using a single-subject experimental design $\rm(A\sb1BCA\sb2)$ which included measures of central tendency and other quantitative analyses. Substantial variability was found across the acoustic parameters. The amount of variability, however, differed for each subject, and all acoustic parameters were not equally affected. Although there was a large amount of individual subject variability, common trends were also noted among subjects. These trends included F$\sb1$ values that more closely approximated the normative values of Peterson and Barney (1952) than F$\sb2$ values, F$\sb2$ values for back and central vowels that exceeded Peterson and Barney's normative data, and F$\sb2$ values for front vowels that were below Peterson and Barney's (1952) normative values. The data suggest that cochlear implant recipients may use the auditory feedback provided by the implant to monitor and adjust their speech output. It was proposed that such modifications, if indeed they did occur, are due to changes in the length and shape of the vocal tract. Specifically, changes in the anterior oral, posterior oral and pharyngeal cavities.