What relationships exist between nouns and verbs and the use of prepositions, adverbs, and adjectives in children and adolescents who use speech generating devices?

The relationships between the use of nouns and verbs, and other word classes have been well established in the typical language development literature. However, questions remain as to whether the same relationships are seen in the language use of individuals who use graphic symbol-based augmentative and alternative communication (AAC). The aim of the study was to examine relationships between the use of verbs and nouns, and the use of prepositions, adverbs, and adjectives through a secondary analysis of language transcripts taken from 12 children and adolescents who used aided AAC in conversation with an adult. A series of multiple linear mixed-effect regression analyses showed a positive predictive association between the use of verbs and the use of prepositions and adverbs, as well as a positive predictive relationship between the use of nouns and the use of adjectives. The theoretical and practical implications of these findings are discussed.