Mands for Verbalization

Abstract

Verbalization rates of three children exhibiting moderate to severe language delays were increased through the systematic use of adults' instructions for verbalizations, models for verbalizations, and contingent positive consequences following utterances. Daily samples of each child's speech were collected during freeplay periods in a classroom for language-deficient preschool children. In a multiple-baseline design across children, teachers prompted language usage and provided materials and services following requests and descriptions. The results of the study showed that children's verbalization rates doubled to tripled from their baseline levels when the intervention was introduced. The subjects' vocabulary and complexity of utterances increased, as indicated by cumulative rates of novel words and novel word combinations. The classroom display of newly trained words and grammatical structures also increased.