IMPACT OF SUBSTITUTION PATTERNS ON PHONOLOGICAL LEARNING BY MISARTICULATING CHILDREN

Learning and generalization of treated sounds to different word positi ons is a desired outcome of intervention in the phonologically disorde red child's system. Unfortunately, children do not always learn the so und that is treated; nor do they always demonstrate across-word genera lization. One possible explanation for differences in treatment outcom e may relate to the pretreatment substitution patterns used by differe nt disordered children. This post-hoc analysis of treatment data exami nes the effects on sound learning and generalization of consistent ver sus inconsistent substitutes. With a consistent substitute across-word position (CS), the same phone was used in initial, medial and final p osition for a phoneme that was not in the child's inventory. An incons istent substitute was evidenced by a different phone for a target soun d in each position of a word (InAP), or even within word position (InW P) for an error sound. Fourteen children with severe phonological diso rders were treated on an obstruent in initial or final word position. Seven of these children had a consistent substitute for the treated ob struent, two children had variable substitutes across word position, a nd five children had variable substitutes within and across word posit ion. The analysis revealed a tight relationship between pretreatment s ubstitution patterns and learning. The seven children with a consisten t substitute for an error sound learned the sound targeted in treatmen t and generalized this knowledge to other word positions. Children who had variable substitutes across word position learned the treated sou nd, but only in the treated word position. Four of the five children i n the InWP group did not learn to produce the sound targeted in treatm ent in any word position. These results suggest that pretreatment subs titution patterns may be a predictor of learning and generalization in phonologically disordered children.