Sometimes we assume that someone who is blind or has low vision, won’t be able to access and use AAC. This is not true. There are ways to make AAC accessible for those who can’t rely on their sight for icon selection.
After all, AAC users without visual impairments don’t simply rely on sight to select icons. Consistent icon placement in any AAC system allows the user to take advantage of muscle memory. Think of it this way, do you rely solely on vision to type on your keyboard? No. Your hands know where to go. Our vision helps us to ensure accuracy and to correct ourselves when we make a mistake.
For someone who is visually impaired and needs AAC, one option is to add a keyguard to the device. A keyguard is a plastic grid that sits on top of the screen. This can provide tactile cues for navigation. Keyguards can be great when the layout out of the vocabulary set (the grid size) stays consistent. They also benefit those with poor fine motor skills. You can stabilize your hand on the keyguard and more accurately select an icon.
It is possible to use auditory cues for icon selection. This setting allows an AAC user to explore the icons on the screen. The first button press provides an output at a reduced volume. When the user hears the word they want, a second button press speaks the word at full volume.
Another way to use hearing to support word selection is to use auditory scanning. As the speech generating device moves through a scanning pattern, one voice is used to label navigation and vocabulary. When the AAC users activate a switch to make their choice, another voice speaks the message. With some devices and apps, the auditory cues can be channeled through an earbud, so that only the AAC user hears them.
The Use of Touch
Some AAC users may rely on tactile cues by placing their hand on the edge of the screen and sliding over to the word they want. This may be the case for someone with cortical visual impairment (CVI), whose functional vision may be variable, depending on the context.
What about additional tactile cues? With some mid-tech devices, you may be able to use tangible, physical symbols. These can be literal representations of an object, such as a mini cup to represent the word “drink”, or a lego brick to represent the concept of “play”, but they don’t have to be. You can use fabrics and materials with differing textures. A soft piece of fabric could represent the concept of a hug.
A tangible circle could represent “yes”, and an X could represent “no”. Tactile symbols can be placed on a screen overlay for low tech/mid tech SGDs, such as the Go Talk, or the Tactile Symbol Communicator. They can also be placed on cards and used as low tech tools. The Adaptive Design Association of NYC has a catalog of tactile symbol cards that can be used for communication:
Adaptive Design Association Link
Tactile symbols are easier to create for tangible objects, but we know that AAC users need access to Core Vocabulary. Nouns do not a sentence make.
Dynamic Learning Maps, a project out of The University of North Carolina, has developed a series of tactile symbols for Core Vocabulary that can be printed on a 3D printer. Think back to the circle for “yes” and the X for “no”. We can use tactile symbols to represent more abstract concepts, and our AAC users can learn them!
Beyond the use of keyguards, tactile symbols, and auditory prompts, we can also take a look at the role visual contrast plays in making icons/symbols more accessible to those with low vision. With a visual impairment, such as CVI, the individual may be better able to discern particular colors on a black background. Touchscreen devices and apps allow you to change the background color on a symbol, but that might not be enough. You may want to take your own pictures against a black background or find a way to change the color of the symbol itself. This can be done with Boardmaker Mayer Johnson symbols. Many individuals with CVI show a strong preference for red or yellow, lights, and motion.
It also helps to take the surrounding environment into account. If your student relies on contrast to access their vocabulary, it would be best to reduce distracting stimuli in their surroundings. It will be easier for them to focus in a quiet, calm location.
We don’t always know just what someone can see…
What if you are in the midst of trying an AAC app with a client, and you are not sure if high contrast will be of benefit? Is there something you can try that is a down and dirty, quick fix? Perhaps. Apple devices allow you to change the color contrast on the screen of your device. Go into Settings:
Settings → General → Accessibility → Accessibility Shortcut
Try adding Classic Invert Colors. Go back to the AAC app and triple click the home button. This will give your icons white text and outlines, against a darker background. This might not be a long-term solution for your client but might give you some helpful, observational information. Did they respond differently when the colors were changed? It might be worth a try.
As always, you can borrow iPads and software from the AT Lending Library:
Are you outside of Pennsylvania? Check out AT3center.net to find your state’s AT Act program. Click on the image below to download the poster.
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