In the literature, there are many investigations pertaining to effective treatment for individuals with intellectual and speech-language impairment with an emphasis on aided language stimulation (ALS) and augmentative and alternative communication (AAC). Verbal speech of these individuals is often difficult to understand especially to unfamiliar listeners (Beck et al., 2009). Implementation of AAC through voice output communication systems with dynamic displays (Uliano et al., 2009) may be used in accordance with ALS pairing verbal language with symbols on AAC devices (Drager et al., 2006) to assist in improving the overall quality of communication. By using ALS, the goal is to increase the length of multi-symbol messages produced for persons who use AAC. There has been successful research on using AAC modeling on the expression of multi-symbol messages by preschoolers (Binger & Light, 2007). However, there appears to be limited research on individuals in the high school setting using ALS and the production of multi-symbol messages using AAC. The purpose of this investigation was to determine if the use of ALS increased the length of the multi-symbol messages produced by students in high school with a moderate intellectual impairment who use AAC. The treatment, in this Multiple Baseline Across Participants (MBAP) single subject design, involved both production: direct imitation of two-word phrases in an action + object structure during 20 trials per session and the frequency of sessions: two times per week for four weeks. The data were analyzed using visual analysis, slope analysis, percentage of nonoverlapping data, and the Two Standard Deviation Band Method. Three out of the four participants indicated a positive change between the baseline and intervention phase with intervention data increasing in comparison to the flat baseline data, upward trend and slope in a positive direction during the intervention phase, and high percentage (75%) of percentage of non-overlapping intervention data points in comparison to the baseline data. The results indicate a significant change from the baseline to the intervention phase. Data of the fourth participant revealed no change when the intervention was presented. The outcome of this study revealed the ability of three students to produce two-word phrases on their Proloqu02Go™ communication application to facilitate verbal communication within the context of this investigation. The results supported that ALS increased the length of multi-symbol messages produced in three out of four participants specific to this investigation.
