Teaching Imitation to Children with Autism Using Most-to-Least Prompt Fading in Front of a Mirror

Children diagnosed with autism spectrum disorder have difficulty acquiring imitative skills, which may serve as an important factor in developing social skills and language (Miller et al., 2015; Ledford & Wolery, 2010; Young et al., 1994). Research has shown that most-toleast prompting is most effective for children who do not learn quickly (Libby et al., 2008). The goal of this study was to discover whether the presence of a mirror affected the rate of acquisition of imitative behaviors compared to a no-mirror condition, using most-to-least within-session prompt fading. This study used a multiple baseline design across sets of behaviors. Sets of behaviors were chosen for each condition that shared similar topographies, response effort, and automatic sensory consequences. A most-to-least withinsession prompt fading procedure was used for both conditions. Past studies have observed the effects of a mirror on the acquisition of imitative targets, but this is the first study to use a most-to-least within-session prompt fading procedure with a mirror (Miller et al., 2015; Du & Greer, 2014). The results of this study show how a mirror affects the rate of acquisition of imitation when using most-to-least within-session prompt fading. TEACHING IMITATION IN FRONT OF A MIRROR 3 Introduction Imitation is important for the acquisition of new behaviors, and also may serve as an important factor in developing social skills and language (Miller et al., 2015; Ledford & Wolery, 2010; Young et al., 1994). If a child can imitate a peer or adult, that child has the opportunity to acquire a wide range of behaviors the peer or adult may be engaging in. Unfortunately, children diagnosed with autism often have difficulty acquiring this skill (Miller et al., 2015; Ledford & Wolery, 2010). A study by Miller, Rodriguez, and Rourke (2015) aimed to determine whether the use of a mirror facilitated the acquisition of imitative behaviors in children with autism. In this study, the experimenters taught a two-year-old boy imitation in conditions with and without a mirror. The researchers hypothesized that the use of the mirror would allow additional feedback to the student, and found that it led to a faster acquisition of the imitative behaviors compared to the mirror-absent condition (Miller et. al, 2015). The researchers used “progressive prompt-delay,” using full and partial physical prompts and providing those prompts immediately or after a previously specified delay depending on the phase (Miller et. al, 2015). The definition of how the researchers implemented partial physical prompts was not provided in the article. Prior to Miller, Rodriguez, and Rourke’s study, there had only been one other study which experimented with this use of the mirror (Miller et al., 2015; Du & Greer, 2014). In the study by Du and Greer (2014), the participants were six preschool-age children, three of which were exposed to the mirror condition and three of which were exposed to a mirrorabsent condition. The researchers did not provide prompts prior to the opportunity for responding. In both studies, participants acquired the imitative responses more quickly with TEACHING IMITATION IN FRONT OF A MIRROR 4 the mirror condition compared with the mirror-absent condition (Miller et. al, 2015; Du & Greer, 2014). In Ledford and Wolery’s (2010) review of the literature on generalized imitation, the researchers reviewed 15 articles that were chosen based on specific inclusion criteria. These criteria included that the articles: were published in peer-reviewed journals, included at least one child younger than 7 years and 11 months with a disability, included at least one independent variable as the “systematic manipulation of one or more instructional components” with the intended purpose of increasing imitation in participants, had at least one dependent variable as a quantitative measure of imitation responses, used a research design that included a baseline condition, and had a primary focus of using imitation to acquire new behaviors, rather than teaching imitation (Ledford & Wolery, 2010). After reviewing all of the articles, the researchers concluded that improvements need to be made in order to determine which instructional method is most effective. However, they did include suggestions for further research to improve upon, which included having specific prompting strategies, embedding instruction across activities and contexts, and teaching imitation with multiple models, including both peers and adults (Ledford & Wolery, 2010). Libby, Weiss, Bancroft, and Ahearn (2008) conducted a study to compare the effectiveness of least-to-most (LTM) prompting and most-to-least (MTL) prompting. For LTM prompting, the child is given a brief opportunity to respond independently, and if they do not, the least intrusive prompt is given, followed by more intrusive prompts if necessary. For MTL prompting, the child is given the most intrusive prompt when first learning a skill, and the intrusiveness of the prompt is decreased over time when the child demonstrates success at the current prompt level (Libby et al., 2008). The researchers concluded that TEACHING IMITATION IN FRONT OF A MIRROR 5 MTL prompting leads to less errors, but in some cases, it may slow down the learning process for the child if they are ready to move on to less intrusive prompts more quickly (Libby et al., 2008). The LTM prompting procedure was more effective for the participants who were learning quickly, but slowed down the learning process for the participants who were having difficulty with the program. Libby et al. (2008) also compared the effectiveness of LTM prompting, MTL prompting, and a MTL prompting with a time delay procedure. The researchers concluded MTL prompting with a time delay was the best option of the three if the child’s learning history was unknown. In this study, the procedure used was a MTL within-session prompt fading procedure. We chose a MTL procedure instead of a MTL with time delay procedure because the participants had previously struggled with acquiring imitation, so a time delay might have impeded the participants’ progress. The intrusiveness of prompts was decreased when the child repeatedly responded correctly with the current prompt, and increased when the child repeatedly responded incorrectly with the current prompt. We developed explicit instructions on how prompting should be implemented and clear criteria for fading the prompt intrusiveness. This procedure was performed in both mirror and mirror-absent conditions, and the rate of acquisition of the imitative behaviors in both conditions were compared. This study expanded upon the research by Miller et al. (2015) and Du & Greer (2014). However, this is the first study that combines the mirror procedures with MTL within-session prompt fading. The participants were two preschool-age students at West Campus who had been exposed to a LTM imitation procedure but still had not acquired imitative skills.