Consonant ordering in Down's syndrome phonology.

This paper explored one aspect of the phonology of a 4-yr-old child with Down's Syndrome. This child had a phonological constraint that ordered his consonants from those produced at the front of the mouth to those produced at the back of the mouth. This meant that in a CVC word, C1 could either be produced at the same place in the mouth as C2, or at a place more forward than C2, but that C1 could not be produced at a place in the mouth posterior to C2. It is argued in this paper that this Consonant Ordering Strategy (COS)--which is equivalent to Ingram's fronting strategy (Ingram, 1974a)--motivated all the consonant substitutions found in the subject's attempted pronunciations of CVC words. The paper concludes by showing the value of an analysis that recognize phonological strategies and larger-than-phoneme units.