Metrical analysis of the speech of children with suspected developmental apraxia of speech

Previous studies have shown that metrical analysis accounts for syllable omissions in young normally developing children better than prior perspectives. This approach has not yet been applied to children with disorders. Inappropriate sentential stress has been proposed as a diagnostic marker for a subgroup of children with suspected developmental apraxia of speech (SD-DAS), suggesting that the application of metrical perspectives to this population may be appropriate. This report extends the goal of identifying diagnostic markers for SD-DAS using analytic procedures from metrical phonology. The lexical metrical patterns of children with SD-DAS were compared to those of a group of children with speech delay (SD) to verify the applicability of metrical constructs to children with disorders while at the same time seeking lexical stress characteristics that might be useful for differential diagnosis. The lexical stress errors of children in both the SD and SD-DAS disorder groups were found to conform to patterns identified in metrical studies of younger normally developing children, confirming the applicability of this approach to children with disorders. Lexical metrical patterns did not differentiate the groups from each other. However, syllable omissions persisted to much later ages in the SD-DAS subjects, especially those children previously identified as having inappropriate phrasal stress. Further metrical studies of the speech of children with suspected SD-DAS are needed, both at the lexical and the sentential level, using both perceptual and acoustic measures.