Unusual and subtle phonological behavior in the speech of phonologically disordered children.

Evidence is reviewed regarding three types of unusual and/or subtle phonological behaviors in the speech of phonologically disordered children. The models of child phonology that are compatible with these behaviors are then discussed. Considered are the nature of the child's stored forms for words, the types of rules operating on these forms as well as those responsible for the surface form of the words, and the nature of the phonological categories reflected in the child's usage. The paper concludes with the implications these considerations have for assessment and treatment.