Effects of symbol arrangement and background color cues on reaction time and accuracy: Implications for AAC design for young children
Open Access
- Author:
- Thistle, Jennifer J
- Graduate Program:
- Communication Sciences and Disorders
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- May 15, 2014
- Committee Members:
- Krista M Wilkinson, Dissertation Advisor/Co-Advisor
Krista M Wilkinson, Committee Chair/Co-Chair
Janice Catherine Light, Committee Member
Carol Anne Miller, Committee Member
David Brent Mcnaughton, Committee Member - Keywords:
- Augmentative and alternative communication
background color
symbol arrangement
visual search
children
AAC display design - Abstract:
- Children who are unable to use spoken language to meet their communication needs often benefit from aided augmentative and alternative communication (AAC). The design of the visual display may influence the ability of the child to communicate effectively. A display that supports efficient visual processing may facilitate success, whereas a display that is not optimal may create unintended barriers to success. However, there is limited evidence guiding clinical decision-making regarding visual display design. This is especially true regarding clinical practices targeted at supporting syntactically correct multi-symbol constructions. Clinicians often arrange symbols in groupings by part of speech as well as color-code the symbol background. In order to address this research to practice gap, the current study implemented a 2 x 2 factorial design to investigate the influence of symbol arrangement and background color on response time and task accuracy. The experiment measured the response time and accuracy of children with typical development, ages 3 ½ to 7 years as they used symbols to repeat spoken sentences. Participants received an auditory-visual stimulus (e.g., spoken sentence matching a photograph) and then touched the symbols within a 4 x 4 array that represented the stimuli. The participants completed the task across four conditions that varied the presence and absence of symbol arrangement and background color. A grammaticality judgment task assessed participants’ metalinguistic awareness to determine if this skill moderated the relationship between the features and outcome measures. Symbol arrangement influenced responding, in the participants under age 5. These participants were faster and more accurate when using displays that had symbol arrangement than when using displays that did not have symbol arrangement. Additionally, individual level analyses illustrated the younger participants (under age 5) were on average 4.3 seconds faster when using displays with symbol arrangement as opposed to no symbol arrangement. As a group, younger participants demonstrated greater accuracy when symbols had a white background compared to colored background. Children over 5 years old demonstrated no effects of symbol arrangement or background color. This dissertation discusses the results, theoretical implications, clinical implications, and directions for future research.