Choosing a suitable vocabulary is a fraught process, often due to uncertain potential, insufficient trial time, conflicting perceptions, lack of knowledge, varying performance, poor goal-setting & inadequate data collection/analysis.
English, with all its challenges & complexities remains the simple goal, not a conveniently simplified & distorted version that is good enough for AAC users. Complete command of language, including full literacy, is the pinnacle, but there are many interim & intermediate stages that are valuable & worthwhile to the varied array of people using AAC systems.
An important consideration is to choose an AAC system that has the capacity to truly grow with the child along the AAC journey. Children of two & a half to three years of age are striving to express themselves with difficult pronouns & verb tenses (1). Can the AAC system being evaluated cope with this sort of demand while still being able to expand further to offer mature, precise language?
Young children dependent upon AAC also need a language system that can blend in emergent literacy through spell-based options & phonetics in conjunction with symbolic representation of words.
A good AAC system will already contain all the core & fringe vocabulary an emergent communicator could need. However, customisation should always be available within the program in a quick & easy manner, ensuring that new words & all correct morphology can be included. Often personalisation & keywords specific to a single user & their family & peers, is a terrific motivator & ensures better engagement.
Included vocabularies should reflect known word lists that are appropriate to various developmental milestones, having referenced the large body of research in natural language development & more AAC specific data.
Robust AAC systems are able to accommodate prescription errors. Trials often last only 2 to 3 weeks at best & may overestimate a child's ability to progress or seriously underestimate it. This is often the case with a first encounter with AAC. It might be necessary to shift from one grid size to another.
Liberator's Accent range provides the 3 Methods of Representing Language, plus each device offers a full array of grid sizes, from 4, 8, 15, (all single-hit only) through to 18, 36, 45, 60, 84 & 144 (all both single-hit & sequenced [Unity} options). The larger they are the greater the richness of vocabulary while ease of navigation is improved.
The Accents additionally contain Page-Based options, Core Scanner (unique switch accessed core vocabulary-focussed), easyChat (single-hit + text), Essence (text-based), LAMP Words For Life (84 location only), WordCore & WordPower vocabularies. Symbol sets can include Minsymbols & PCS.
The NovaChat range comprises many (single-hit) vocabularies Multi-Chat (15 grid size), My Quick Chat (4, 8, 12 grid sizes), WordPower (20, 25, 42, 48, 60, 80, 108 grid sizes), Essence (text) & Vocab PC. Symbol sets include SymbolStix & PCS.
Liberator's own rugged LR7 device can be loaded with either LAMP Words For Life (84 location) or the full NovaChat software range, or even both together.
- Baker & Sementelli, Closing the Gap 2005