The Evidence
None Of This Is A Guess.
Parkinson's takes volume and steadiness first. The evidence below is why the targets are large and forgiving, why banking happens before the whisper, and why support design matters more than grid design.
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Every finding below names its sources. Where the field has no evidence, we say so instead of implying otherwise. Where Grand Voice OS goes beyond the literature, we mark it as our extension, not as a study result. Ask us for any source in full: admin@titaniumdigitalholdings.com.
What The Evidence Says
Consistent symbol location is the single best-replicated learnability finding in AAC research. Motor plans build around position, and moving a word costs the user the practice they paid for. Every GVOS board obeys this as law.
Thistle 2018; Dukhovny & Gahl 2014
Typical aided communication runs 8 to 10 words per minute. Phrase-based prestored speech measured 36 to 64 words per minute. That is why banked phrases, pinned folders, and one-tap libraries sit at the center of the system.
Todman 2000
Clinical practice pioneered at Boston Children's Hospital showed that banking whole recorded phrases, with their real intonation, preserves identity in a way synthesized speech alone cannot. Bank Your Voice and Studio Script are built around both the voice and the phrase.
Costello, Boston Children's Hospital message banking practice
Roughly one in three AAC devices ends up abandoned, and the drivers are support factors: training, caregiver enablement, upkeep, and vocabulary relevance. The kit ships with the family guide, coached phrase authoring, and a companion that teaches, because the device that stays in use is the one the whole household knows how to live with.
Phillips & Zhao 1993; Johnson 2006; Moorcroft 2019, 2020; Pape 2002
Communication-partner training is one of the most cited unmet needs in AAC, and untrained partners are a leading driver of abandonment. Every kit ships with How to Talk with Me because listening is a skill the family deserves to be taught.
Communication partner instruction literature; AAC abandonment studies
The retention stories in the literature are personal: vocabulary embedded in real roles and routines. GVOS's coached library building and the learning that stays on the device exist because relevance is what survives month six.
Ryan 2021; Pape 2002
Still Being Compiled
The dossier grows. These are the source sets currently being compiled for this page, named so the gap is visible instead of hidden: