Further evaluation of emerging speech in children with developmental disabilities: training verbal behavior.

The conceptual basis for many effective language-training programs are based on Skinner's (1957) analysis of verbal behavior. Skinner described several elementary verbal operants including mands, tacts, intraverbals, and echoics. According to Skinner, responses that are the same topography may actually be functionally independent. Previous research has supported Skinner's assertion of functional independence (e.g., Hall & Sundberg, 1987; Lamarre & Holland, 1985), and some research has suggested that specific programming must be incorporated to achieve generalization across verbal operants (e.g., Sigafoos, Reichle, & Doss, 1990). The present study provides further analysis of the independence of verbal operants when teaching language to children with autism and other developmental disabilities. In the current study, 3 participants' vocal responses were first assessed as mands or tacts. Generalization for each verbal operant across alternate conditions was then assessed and subsequent training provided as needed. Results indicated that generalization across verbal operants occurred across some, but not all, vocal responses. These results are discussed relative to the functional independence of verbal operants as described by Skinner.