Doctor of Philosophy (PhD)


Communication Sciences and Disorders

Document Type



Previous research has demonstrated that individuals with stroke-induced aphasia can use augmentative and alternative communication (AAC) when they cannot meet their communication needs using spoken language (Dietz, Weissling, Griffith, McKelvey, & Macke, 2014; Purdy & Van Dyke, 2011). Of the various interfaces found in the different AAC systems, the grid display and the visual scene display (VSD) have been used by individuals with aphasia (Hough & Johnson, 2009; Dietz et al., 2018). However, there is a scarcity of research examining the comparative usefulness of these interfaces.

This prospective study attempted to understand how neurologically healthy individuals of different ages and varying levels of technology experience describe composite pictures using the grid and VSD interfaces presented on a high-tech AAC system.

The study included three groups: 18 young adults (18 to 39 years), 24 older adults with technology experience, and 20 older adults with limited technology experience. Both older adult groups were age ranged between 60 to 91 years. Participants described two composite pictures with each AAC interface presented on an iPad. They were allowed 4-minutes to describe each picture.

A mixed between and within-subject design was utilized to analyze three dependent variables: 1) the total number of correct information units (CIUs; Nicholas & Brookshire, 1993), 2) the percentage of CIUs, and 3) CIUs per minute.

The study results show a significant difference between each older adult group and the younger adult group for total CIUs (p < .000) and CIUs per minute (p < .000). There was no significant difference across the two older adult groups. Additionally, there was no significant difference in performance across the two interfaces for any of the groups.

The findings show that age does impact performance, with young adults producing more CIUs and more CIUs per minute than older adults. However, the difference in technology experience found in the older adult groups did not impact performance. Furthermore, both interfaces used in the current study were equally beneficial for describing pictures.

Committee Chair

Donovan, Neila