Developmental influences in teaching language forms to individuals with developmental disabilities.

The purpose of this experiment was to test the assumption that the sequencing of language goals for individuals with developmental disabilities should be based on the normal developmental sequence. In a series of two studies, phonetic sounds and syntactic structures representing different levels of normal development were taught to individuals with developmental disabilities. The results showed that (a) the majority of earlier emerging forms were acquired in fewer trials, (b) there was never an instance when the later emerging form was acquired and the earlier emerging form was not, and (c) the majority of earlier emerging forms were correctly produced at higher levels than the later emerging forms during probe sessions conducted 6 months after training. The results are discussed in terms of their implications for the development of language curricula for individuals with developmental disabilities.