Young, H., Pope, L., Therrien, M., Light, J. (2017 March). The effect of seated positioning on access to AAC. Poster presentation at Pennsylvania Speech-Language Hearing Association (PSHA) convention in Harrisburg, PA. [Handout]
Objective: Individuals with cerebral palsy (CP) often have difficulty speaking and may require AAC to facilitate full participation in life. The purpose of this study was to investigate the effect of seated positioning on the accuracy and efficiency of a single motor act used to access AAC for an adolescent with athetoid CP.
Method: A single-subject alternating treatment design was used with one 14-year-old participant to compare the effects of two seated positions: the participant’s original seated position (OSP) and the participant’s new seated position (NSP) which followed the conventions of functional seating as outlined by Costigan and Light (2010). With each seated position, the participant used his head to activate an iPad via a mounted jellybean switch. Dependent variables consisted of accuracy of target selection, measured in terms of movement initiation and movement termination, and response time to accurate target selection (latency). Data were graphed separately across seated positions and were analyzed for changes in accuracy and latency between seated positions. Results. Latency was less variable within and across sessions in NSP; this pattern was most pronounced in the final three sessions. A positive learning curve in accuracy was observed in NSP, reaching 90% by the final three sessions. Accuracy did not improve in OSP.
Conclusion: Results offer empirical evidence regarding the importance of considering seated positioning when determining access methods for adolescents with CP, underscoring the importance of a multidisciplinary team in the provision of AAC services for individuals with significant speech and motor impairments.
This study is part of the larger RERC on AAC effort towards developing multimodal technologies to improve access.