On Word-Initial Voicing: Converging Sources of Evidence in Phonologically Disordered Speech

The purpose of this study is to bring related sources of data, i.e., phonological and acoustic phonetic, to bear on the characterization of two children's disordered phonological systems. Auditorily-based phonological analyses indicated that the children exhibited a superficially similar pattern of error involving the voice contrast in word-initial obstruent stops, even though both children accurately produced the voice contrast in post-vocalic stops. Acoustic phonetic analyses indicated, however, that one of the children systematically effected the voice distinction using closure duration and voice onset time, whereas the other child did not. Despite the similarity of their errors as assessed by auditorily-based phonological analyses, the children had very different productive knowledge of word-initial voicing in stops. These findings have implications for the clinical assessment and treatment of children with phonological disorders.