Augmentative communication systems taught to cerebral palsied children--a longitudinal study. I. The acquisition of signs and symbols, and syntactic aspects of their use over time.

A longitudinal study of augmentative communication training with 40 language-impaired, cerebral palsied children examined the acquisition of Blissymbols and Makaton Vocabulary signs and syntactic aspects of their use over an 18-month period. The children made measurable gains in these areas over time, but progress was very slow and they continued to show severe limitations in the repertoires of signs/symbols they acquired and in the average number, length and complexity of utterances they produced in semi-structured conversational settings. Possible reasons for these findings are discussed with reference to subject and system characteristics, and the teaching practices adopted in the schools. Comparisons between the Bliss and signing groups suggest that neither augmentative system facilitated greater progress in sign/symbol acquisition and use than the other. However, there was wide variability in performance among the children within each group.