EFFECTS OF LEXICAL INTERVENTION ON THE PHONOLOGY OF LATE TALKERS

The purpose of this investigation is to determine whether a focused st imulation intervention focusing on lexical training has indirect, seco ndary effects on children's phonological abilities. Twenty-five toddle rs with expressive vocabulary delays and their mothers were randomly a ssigned to intervention and control groups. The children were between 23 and 33 months of age at entry into the study and were at the single -word stage of language development. Parents of late talkers in the ex perimental group were trained to employ frequent, highly concentrated presentations of target words without requiring responses. Two measure s of phonological diversity (i.e., syllable structure level and conson ant inventory) and one measure of accuracy of production (i.e., percen t consonants correct) were measured prior to and following interventio n within the context of mother-child interactions. The toddlers who re ceived intervention made treatment gains in two areas of phonological ability. They used a greater variety of complex syllable shapes and ex panded their speech sound inventories to include more consonant sounds in both initial and final position. In contrast, there were no effect s of language treatment on the accuracy of correct production when com pared to the adult phonological system.