Recognition of Vocabulary in Children and Adolescents with Cerebral Palsy: A Comparison of Two Speech Coding Schemes

The effects of speech ability (speaking versus non-speaking) and type of AAC presentation scheme (static versus dynamic) on vocabulary recognition were examined for children and adolescents with cerebral palsy using an extensive test-with-feedback procedure. Participants initially made fewer errors on the static scheme than on the dynamic scheme, primarily because of the low noun error rates associated with the static scheme. Error rates for presentation schemes became equivalent by the third trial and by the eighth trial, performance was better for the dynamic scheme. The primary cause of errors on the dynamic display was found to be difficulty in recognizing each target's category. On the static display, participants had difficulty recognizing word-icons and correct part-of-speech. These results indicate that unique difficulties in vocabulary recognition arise for each presentation scheme. Additionally, individual differences affected performance across presentation schemes, instead of differentially affecting them. Specific training implications are discussed.