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Effect of visiographic contextualization on navigation of an AAC system by survivors of severe brain injury
Survivors of severe acquired brain injury (ABI) often have unmet communication needs requiring augmentative and alternative communication (AAC). Survivors may have difficulty with AAC systems requiring extensive new learning. Specifically, navigation challenges occur in survivors who display cognitive inflexibility and other executive function impairments because of: (a) problems interpreting different image types used to represent concepts within AAC systems, and (b) mismatches between conversations and AAC system organization. This study's purpose was to examine the effect of cognitive flexibility, image contextualization, and prompt type on AAC navigation accuracy and speed by ABI survivors. Subsequently, inaccurate navigation attempts by people failing a cognitive flexibility measure were examined.^ Eighteen ABI survivors formed two participant groups: 10 survivors passing and 8 survivors failing a cognitive flexibility measure. Participants located 60 words on three, 3-level AAC systems given either matching context or no-context prompts. Each system used a different image type to represent content: high-context, low-context, or no-context photographs. The researcher computed mixed ANOVAs, appropriate follow-up statistics, and error analyses. Results showed that participants failing the cognitive flexibility measure navigated the system less accurately than participants passing the measure; no group difference occurred regarding accurate response navigation speed. For image contextualization, a trend for greater accuracy occurred in the high-context and low-context conditions than in the no-context condition; however, speed of accurate response navigation was slower with high-context photographs than low-context and no-context photographs. Regarding prompt type, both participant groups were more accurate given matching context than no-context prompts, and navigation speed to accurate responses was faster given matching context than no-context prompts. Error analysis using responses from participants failing the cognitive flexibility measure indicated variability regarding error types. Overall, findings suggest that performance on a cognitive flexibility measure may help clinicians distinguish survivors likely and not likely to struggle with AAC navigation. Also, variability among survivors highlights the importance of performing individualized evaluations when making decisions about image contextualization within a system.^
Wallace, Sarah E, "Effect of visiographic contextualization on navigation of an AAC system by survivors of severe brain injury" (2009). ETD collection for University of Nebraska - Lincoln. AAI3366687.