Acoustic and perceptual analysis of word-initial stop consonants in phonologically disordered children.

Spectrographic measures of voice onset time (VOT) were made for phonologically disordered children in whom a voicing contrast was just beginning to emerge. These temporal measures were related to adult listeners' perception of voicing of the initial stop consonant to determine how well VOT could predict perceived voicing. In general, the predictive utility of VOT was not very high.

Untrained acquisition of /s/ in a phonologically disordered child.

The untrained /s/ productions of a phonologically disordered child were followed over a period of several months as she produced /s/ in imitated words and in spontaneous connected speech. For this child, as has been reported in the literature for children acquiring phonology normally, /s/ occurred earliest in the word-final position, appearing in word-initial position only several weeks later. Two word-medial, or intervocalic, contexts were compared: (a) monomorphemic words in which /s/ is word- and morpheme-medial (e.