Effect of Fixed Array AAC Graphic Symbols on Sentence Construction

Abstract

Objectives: Despite the dominant use of grid-based augmentative and alternative communication (AAC) displays, the effect of fixed array of graphic symbols has not been thoroughly studied, which makes it challenging for clinicians to provide evidence-based AAC intervention to individuals with complex communication needs. The current study aimed to determine the effect of fixed array symbols on sentence composition. Methods: Thirtytwo healthy adults between 20 to 30 years old participated in the study. They were asked to locate three symbols in a fixed array condition and a non-fixed array condition for 25 identical noun-adverb-verb target sentences. The difference in accuracy and response time was analyzed by using a non-parametric two-related samples test and a Spearman correlation test. Results: Although there was no difference in the number of correct responses, participants showed significantly faster responses in the fixed array condition than in the non-fixed condition. Regardless of the selection order, participants located symbols faster in the fixed array condition. As the number of exposures to the located symbols increased, the total selection time in the fixed array condition decreased moderately. Conclusion: The findings support the idea that a fixed array condition may facilitate locating a sequence of graphic symbols in an AAC system by reducing cognitive load in recalling the location of target symbols.