Comparing Different Classes of Reinforcement to Increase Expressive Language for Individuals with Autism

One of the basic principles of applied behavior analysis is that behavior change is largely due to that behavior being reinforced. Therefore the use of positive reinforcement is a key component of most behavioral programs for individuals diagnosed with autism. In this study we compared four different classes of reinforcers (i.e., food, praise, toys, and feedback) on the rate of skill acquisition for three individuals diagnosed with autistic disorder. Using a parallel treatments design, the results of this study showed that all four classes of reinforcement were effective for teaching all of the participants. Results also indicated that food reinforecers were more efficient and more preferred. Finally, participants performance during teaching was idiosyncratic across the three participants. One of the basic principles of Applied Behavior Analysis (ABA) is that behavior change can be instigated through the use of positive reinforcement (e.g., Catania, 1998). For individuals diagnosed with an Autism Spectrum Disorder (ASD), researchers have demonstrated reinforcement-based procedures to be effective in decreasing self-injurious behaviors (e.g., Worsdell, Iwata, Hanley, Thompson, & Khang, 2000), aggression (e.g., Repp & Deitz, 1974), and self-stimulatory behaviors (e.g., Singh, Dawson, & Manning, 1981). Additionally, researchers have shown that reinforcement can be used to increase pro-social skills such as: social skills (e.g., Leaf, Dotson, Oppenheim, Sheldon, & Sherman, 2010), language (e.g., Petursdottir, Carr, Lechago, & Almason, 2008), and academic and pre-academic tasks (e.g., Leaf, Sheldon, & Sherman, 2010). Positive reinforcers can take many forms including food (e.g., Schreibman, 1975), toys (e.g., Leaf, Sheldon, & Sherman, 2010), praise (e.g., Schreibman, 1975), tokens (e.g., Allyon & Azrin, 1968), and even allowing the learner to engage in self-stimulatory behaviors (e.g., Rincover & Newsom, 1985). Since reinforcement-based procedures have been highly effective in changing behavior for people diagnosed with ASD, researchers have conducted numerous studies investigating various aspects of reinforcement. One area of interest has been studying various methods for determining learners preference of various stimuli and whether these preference assessment results are predictive of reinforcer effectiveness. Researchers have evaluated single-item presentation (e.g., Pace, Ivancic, Edwards, Iwata, & Page, 1985), paired preference assessment (e.g., Fisher et al., 1992), and multiple stimulus preference assessment (e.g., Carr, Nicolson, & Higbee, 2000) for evaluating learner preference among stimuli and the correlation of preference level with reinforcer effectiveness. The research has indicated that all three assessments are effective in determining both preference and reinforcement effectiveness and that these formal assessments are more accurate than asking teachers or parents (Green et al., 1988). A second area that has been evaluated in the reinforcement literature is determining if children prefer contingent or non-contingent reinforcement (e.g., Luczynski & Hanley, Correspondence concerning this article should be addressed to Justin B. Leaf., 200 Marina Drive, Seal Beach CA 90740. E-mail: Jblautpar@aol.com Education and Training in Autism and Developmental Disabilities, 2014, 49(4), 533–546 © Division on Autism and Developmental Disabilities Comparing Reinforcement Classes / 533 2009). Luczynski and Hanley (2009) evaluated eight typically developing children’s relative preference of contingent reinforcement as part of a differential reinforcement of alternative behavior (DRA) procedure versus noncontingent reinforcement to increase social interaction. Results indicated that 7 of the 8 participants preferred contingent reinforcement. Although these findings are important, they were conducted with typically developing children; therefore, it is not known if findings would be similar for children with ASD. Additional areas of focus in the reinforcement literature include how the amount (magnitude) of reinforcement affects behavior change (e.g., Roscoe, Iwata, & Rand, 2003), the effects of various reinforcement schedules (e.g., Worsdell et al., 2000) on behavior change, the differences between positive and negative reinforcement on behavior change (e.g., DeLeon, Neidert, Anders, & Rodriquez-Catter, 2001), and how learners’ choice of reinforcement influences behavior change (e.g., Smith, Iwata, & Shore, 1995; Tiger, Hanley, & Hernandez, 2006). Despite the amount of research on different components of reinforcement, very few studies have evaluated how different classes of reinforcers (e.g., food, toys, or social) can affect skill acquisition. Ferrari and Harris (1981) evaluated three different classes of reinforcement: sensory reinforcers (i.e., vibration, music, and strobe light), social reinforcement, and food reinforcement on four children diagnosed with ASD. The first task evaluated was how frequently participants were able to press a clown’s nose (e.g., bar pressing) during a 15 min session. The second task evaluated how well the participants were able to receptively identify objects in a field of three. Results were idiosyncratic across the five participants. The results did show that: (a) sensory reinforcement can be as effective as other classes of reinforcement for children with ASD; (b) that food and praise were reinforcing for the five participants; and (c) that vibration appeared to be the most effective of the sensory stimuli. In a later study, Rincover and Newsom (1985) compared the satiation effects of two classes of reinforcement: sensory (e.g., tickles, therapist finger tapping, and hand clapping) to food reinforcers on a two-choice visual discrimination task. The authors selected five sensory reinforcers and five food reinforcers for each participant based on interviews and direct observations. Results of the study indicated that sensory reinforcement was more resistant to satiation when multiple reinforcers were presented during a teaching session. In another study, Charlop, Kurtz, and Casey (1990) compared food reinforcers to using participants’ self-stimulatory behaviors as reinforcers on skill acquisition for children diagnosed with ASD. Results of this study indicated that task performance was higher when the researchers used a participant’s own self-stimulatory behaviors rather than food reinforcers. Thus, across the three studies it appears that sensory reinforcement can be more effective than food reinforcement when teaching children a variety of tasks. Furthermore, sensory reinforcement might be more resistant to satiation. Despite these findings there are still several questions, which should be explored by researchers. For one, the research comparing reinforcement classes for children diagnosed with ASD remains limited. Second, the previous research did not utilize formal assessments of different potential reinforcers, so it is not known if the researchers did indeed choose the most preferred reinforcers within a reinforcement class. Third, none of the studies incorporated participant choice, which has been shown to influence the effectiveness of reinforcement. Finally, none of the studies have compared different reinforcement classes to feedback (e.g., “Yes” or “No”) alone. Thus, the purpose of this study was to evaluate three reinforcement classes (i.e., food reinforcement class, toy reinforcement class, social reinforcement class) and feedback-only on skill acquisition for three children diagnosed with autistic disorder. This study evaluated the skill acquisition, maintenance, efficiency, and participant preference for each of the five participants.