Eye-tracking Measures Reveal How Changes in the Design of Aided AAC Displays Influence the Efficiency of Locating Symbols by School-Aged Children without Disabilities

Abstract

PURPOSE: Many individuals with communication impairments use aided AAC systems involving letters, words, or line-drawings, that rely on the visual modality. It seems reasonable to suggest that display design should incorporate information about how users attend to and process visual information. The organization of AAC symbols can influence the speed and accuracy with which children select a target symbol on a display. This research examined why some displays facilitate responding. METHOD: Eye-tracking technology recorded point-of-gaze while nondisabled children engaged in a visual search task with two AAC displays. In one, symbols sharing an internal color were clustered together. In the other, like-colored symbols were distributed. Dependent measures were latency to fixate on the target compared to distracters, and the number of fixations to target and distracters. RESULTS: Participants were significantly slower to fixate on the target when like-colored symbols were distributed, with a significant increase in the number of fixations to distracters that did not share color with the target. CONCLUSIONS: Efficient search was related to minimizing fixations to non-relevant distracters. Vulnerability to distraction can be a significant problem in individuals with disabilities who use AAC. Minimizing the intrusion of such distraction may therefore of importance in AAC display design.