Design Characteristics of Augmentative and Alternative Communication Interfaces for Children With Cortical Visual Impairment
Jamie B. Boster, Kevin Pitt, Kathryn Brown, Julie Potts, & Overholt
Department of Speech Pathology, Nationwide Children's Hospital, Columbus, OH
Department of Special Education and Communication Disorders, University of Nebraska-Lincoln
There are children with cortical/cerebral visual impairment (CVI) who require augmentative and alternative communication (AAC) systems, yet most AAC interfaces are visually complex and not designed to accommodate the needs of CVI. To address this gap, Boster and colleagues conducted two virtual focus groups with nine vision professionals—eight Teachers of the Visually Impaired and one optometrist—to identify AAC design features for CVI that may better support communication access for this population.
Using qualitative thematic analysis of discussions about 25 sample AAC interface elements, the researchers identified three major themes: interface design characteristics, individual CVI visual traits, and the importance of scaffolding over time.
Vision professionals emphasized the value of dark backgrounds to reduce visual clutter, along with strong—but natural—contrast between symbols and backgrounds. Smaller grids with larger icons may support early access, though they may restrict vocabulary. Real objects and personalized photographs were strongly preferred over abstract symbols, with progression toward line drawings and text occurring gradually. Excess visual clutter, including combining text and pictures on the same button, was cautioned against. Preferred colors and visual field preferences should guide layout decisions.
A central finding was the importance of developmental scaffolding: object → photo → symbol → text, with supports added or faded as skills emerge. Participants stressed that design must be individualized and responsive to functional vision.
Although limited by a small sample size, the study provides important interdisciplinary insight. The authors conclude that effective AAC for children with CVI requires collaboration between vision and communication professionals and thoughtful, evidence-informed interface customization to ensure meaningful language access.
Main Research Question
What are the key design characteristics of augmentative and alternative communication (AAC) interfaces that vision professionals consider essential for children with CVI and complex communication needs?
Methodology
The study used a qualitative focus group methodology, conducting two virtual 1-hour focus groups with eight teachers of the visually impaired (TVIs) and one optometrist. Discussions were recorded and analyzed using thematic analysis to identify recurring patterns and themes.
Image Description: A young woman looks at her AAC device and makes a selection from the tablet screen, which displays a handful of words in white text on a black background for visual access.
Key Findings
The study identified three main themes related to AAC interface design for children with CVI:
1 Design Characteristics of the AAC Interface
- Preferred background colors: Black or gray backgrounds with high contrast.
- Grid size: Start with fewer, larger icons and increase complexity over time.
- High contrast: Essential for image clarity, but extreme unnatural contrasts were strongly discouraged.
- Movement: Can capture attention but may also be distracting.
- Outline and spacing: Borders around icons and appropriate spacing improve usability.
- Symbolic representation: Real objects and real-life photographs are preferred over generic icons.
2 Characteristics of Children With CVI to Consider in AAC Interface Design
- Preferred colors: Children with CVI often have individual color preferences that can support engagement.
- Visual field preferences: Understanding a child’s dominant visual field can optimize AAC interface layout.
3 Scaffolding the Development of AAC Interface Elements Over Time
- Progression from tangible objects to real photographs and then to symbolic representations.
- Adjustments to interface elements should align with the child's evolving abilities.
Significance: What This Means for CVI
Children with CVI often have complex communication needs that require AAC systems tailored to their unique visual and cognitive abilities. However, research directly informing AAC design for children with CVI has been limited. This study provides insight into how AAC systems can be optimized to enhance usability and effectiveness for this population and reinforces the importance of individualized design.
It also highlights the importance of interdisciplinary collaboration between speech-language pathologists (SLPs) and vision professionals in designing and implementing AAC solutions.
Conclusions
1 Customization is Key: AAC interfaces should be customized based on the child’s visual abilities and preferences.
2 High Contrast and Simplicity: Background color, spacing, and contrast should be carefully considered to support visual attention and processing.
3 Scaffolding Symbolic Representation: Children with CVI may need to start with real objects before progressing to photos and symbols.
4 Collaboration is Essential: AAC design should incorporate input from vision professionals to ensure accessibility and effectiveness.
5 Future Research Needed: Additional studies should investigate the specific impact of various AAC design elements on communication outcomes for children with CVI.
This study serves as an important step toward developing evidence-based AAC interfaces that better meet the needs of children with CVI, ultimately improving their ability to communicate and engage with the world around them.
Boster, J. B., Pitt, K., Brown, K., Potts, J., & Overholt (2025). Design Characteristics of Augmentative and Alternative Communication Interfaces for Children With Cortical Visual Impairment: Results From Two Focus Groups With Vision Professionals. American journal of speech-language pathology, 34(2), 692–705. https://doi.org/10.1044/2024_AJSLP-24-00318