ABSTRACT
The efficacy of the IBM SpeechViewer's Vowel Accuracy Module for the treatment of vowel productions was evaluated in six preschool children with hearing-impairment over a 4-month period. A single-subject design was used, and the vowels /a/, /i/ and /u/ were treated. Untreated sounds also were probed to monitor for carryover and developmental effects. One of the children was dismissed from the study because of noncompliance. Of the remaining five children, four exhibited a treatment effect for /u/, two for /a/, and one for /i/. Four of the children demonstrated some generalization. Developmental effects, as represented by change in /s/-cluster production, were not documented. Although treatment effects were observed, difficulties with the Vowel Accuracy Module were also observed. These included inaccuracies in the feedback on low-intensity, hypernasal, and high-pitched utterances; inability to sustain the attention of preschoolers over multiple sessions; lack of instructional feedback; and nonlinearity in the criterion-adjustment control.