ASA 127th Meeting M.I.T. 1994 June 6-10

5pSP19. The acoustic vowel space of normal and misarticulating children.

Kristin Tjaden

Ying-Chiao Tsao

Gary Weismer

Waisman Ctr. and Dept. Commun. Disord., Univ. of Wisconsin---Madison, 1500 Highland Ave., Madison, WI 53705

Perceptual and acoustic descriptions of children's articulatory errors typically have focused upon consonant productions, as compared to vowel productions. In the present investigation, three subject groups (15 misarticulating children age 4 to 6 who were referred for clinical services, 15 normally articulating 4- to 6-year-old children, and 15 young adult subjects) produced multiple repetitions of single syllable target words embedded in a carrier phrase. Midpoint (target) formant frequencies of selected vowels were measured and the resulting vowel quadrilaterals were then compared across subject groups to determine if children with so-called phonological delays characterized primarily by consonant misarticulations produced vowel spaces similar or different from normally articulating children. This is an interesting question because the focus on consonants in misarticulating children implies that speech production is guided by segmental strategies, when in fact many children in the 4- to 6-year-old range may be aware of the segmental structure of speech. Perhaps, then, misarticulating children produce vowel spaces that reflect a more global speech delay.