A COMPARISON OF METHODS FOR TEACHING RECEPTIVE LANGUAGE TO TODDLERS WITH AUTISM JOSEPH VEDORA AND KATRINA GRANDELSKI

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1 JOURNAL OF APPLIED BEHAVIOR ANALYSIS 2015, 48, NUMBER 1(SPRING) A COMPARISON OF METHODS FOR TEACHING RECEPTIVE LANGUAGE TO TODDLERS WITH AUTISM JOSEPH VEDORA AND KATRINA GRANDELSKI BEACON ABA SERVICES The use of a simple-conditional discrimination training procedure, in which stimuli are initially taught in isolation with no other comparison stimuli, is common in early intensive behavioral intervention programs. Researchers have suggested that this procedure may encourage the development of faulty stimulus control during training. The current study replicated previous work that compared the simple-conditional and the conditional-only methods to teach receptive labeling of pictures to young children with autism spectrum disorder. Both methods were effective, but the conditional-only method required fewer sessions to mastery. Key words: autism, conditional discrimination training, receptive language Lovaas (2003) outlined a sequential method for establishing the conditional discriminations involved in receptive labeling of pictures. This method involves first teaching simple discriminations in a massed-trial format and then systematically introducing more difficult simple and conditional discriminations over time. Grow, Carr, Kodak, Jostad, and Kisamore (2011) noted that these sequential procedures, referred to as a simple-conditional method, might foster faulty stimulus control, resulting in error patterns. Despite this observation, the simple-conditional discrimination method remains common practice in early intensive behavioral interventions (EIBI; Love, Carr, Almason, & Petursdottir, 2009). Grow et al. s (2011) study suggested that a conditional-only method that involved teaching conditional discriminations from the outset might be more efficient than the simpleconditional method. These findings were replicated in a subsequent study (Grow, Kodak, & Carr, 2014), using a progressive prompt delay Special thanks to Laura Grow for her assistance with data sheets and stimulus presentations. Joseph Vedora is now with the Evergreen Center. Address correspondence to Joseph Vedora (jvedora@ evergreenctr.org). doi: /jaba.167 during instruction in place of the least-to-most prompting procedure used by Grow et al. (2011). The participants in Grow et al. (2014) were 3 and 4 years old, and the participants in Grow et al. (2011) were 4 to 7 years old. Given the recent emphasis on early identification and treatment of autism spectrum disorder (ASD), more research is needed to determine effective interventions for children with ASD under the age of 3 years (Wallace & Rogers, 2010). The present study sought to replicate and extend Grow et al. s (2011, 2014) findings by comparing the simple-conditional and conditional-only methods in the context of home-based EIBI programs with children under the age of 3 years who had been diagnosed with ASD, using a progressive prompt delay similar to that used by Grow et al. (2014). METHOD Participants, Setting, and Materials Curtis was a 2 year 7-month-old boy who had been diagnosed with ASD. He followed 10 onestep instructions, receptively identified approximately 10 body parts, and had learned approximately 40 auditory visual discriminations prior to the study. He communicated through the use of a picture communication system and several 188

2 RECEPTIVE LANGUAGE 189 one-word utterances. At the time of the study, he had been receiving EIBI for 6 months. Sam was a 2-year 1-month-old boy who had been diagnosed with autism. He followed 10 one-step instructions, identified seven body parts, and had learned approximately 10 auditory visual discriminations prior to the study. He vocally manded for several items and tacted approximately 10 objects. He had been receiving EIBI for 4 months. All sessions occurred in the participants homes during regularly scheduled therapy sessions and lasted approximately 5 min. Sessions occurred 2 to 3 days per week. The stimuli were six pictures that depicted actions and were printed on laminated cards (7.62 cm by 12.7 cm). Set 1 (catching, kicking, and walking) was assigned to the simple-conditional method, and Set 2 (brushing, crawling, and cutting) was assigned to conditional-only method for Curtis, and vice versa for Sam. Dependent Variable and Measurement The primary dependent variable was the percentage of correct independent responses, defined as touching the picture card corresponding to the verbal stimulus within 5 s of the sample presentation without errors or instructor-delivered prompts. A second independent observer collected data to assess reliability in 13% of sessions for each participant. An agreement was defined if both observers scored a response as (a) independent correct, (b) prompted correct, (c) incorrect, or (d) no response. Reliability was calculated by dividing the number of agreements by the number of agreements plus disagreements and converting the result to a percentage. Agreement was 100% for each participant. Procedural fidelity data were also collected by an independent observer in 13% of sessions for each participant. The observer scored a correct trial if the instructor presented the correct stimulus arrangement as shown on the data sheet, implemented the correct prompt delay, and delivered the correct consequences for correct and incorrect responses. The average procedural fidelity across sessions was 99% (range, 93% to 100%). Procedure General procedure. During baseline and both instructional conditions, the position and presentation order of verbal stimuli (samples) and picture cards (comparison stimuli) were arranged in a balanced design as described in Grow et al. (2011). At the beginning of each baseline or instructional trial, the instructor presented an array of picture cardsonatableinfrontoftheparticipantandthe verbal stimulus, touch. The number of cards varied depending on the condition or the step of instruction. During instruction, the instructor initially used an immediate point prompt (0-s delay) to indicate the correct card; however, no prompts were used during the simple-conditional steps in which only one card was on the table. Prompts were removed using a progressive prompt delay. After two prompted correct responses, the delay was increased to 2 s, and after two correct independent responses, the delay was increased to 4 s. Sessions always began at the delay at which the previous session ended. Correct responses, independent or prompted, resulted in praise and access to a toy or edible item identified through daily preference assessments. Incorrect responses before the prompt resulted in the re-presentation of the verbal stimulus followed by an immediate point prompt. This error-correction procedure was prescribed for all training steps in both methods, although it was not used on steps in which stimuli were trained in isolation, because no errors occurred and the participants always responded within 4 s. A reinforcer was not delivered after error correction. After two errors in a session, the delay was decreased by 2 s. The mastery criterion, and the criterion for advancement of instructional steps in the conditional-only condition, was 89% correct independent responding in two consecutive sessions. Baseline. Baseline sessions consisted of nine trials. The instructor provided the verbal stimulus touch, and allowed 4 s to respond. No

3 190 JOSEPH VEDORA and KATRINA GRANDELSKI Table 1 Simple-Conditional Method Step Description Sample stimuli Picture cards (comparisons) 1 Simple discrimination without distracter Catching Catching 2 Simple discrimination without distracter Kicking Kicking 3 Simple discrimination with distracter Catching Catching and kicking 4 Simple discrimination with distracter Kicking Catching and kicking 5 Conditional discrimination Catching and kicking Catching and kicking 6 Simple discrimination without distracter Walking Walking 7 Conditional discrimination Walking and catching Walking and catching 8 Conditional discrimination Walking and kicking Walking and kicking 9 Conditional discrimination Walking, catching, and kicking Walking, catching, and kicking differential consequences for correct or incorrect responses were provided. Simple-conditional method. Table 1 depicts Steps 1 through 9 and includes examples of the sample and comparison stimuli for each step, based on the stimuli used with Curtis. For Steps 1, 2, and 6, each of the stimuli in a set were trained as simple discriminations in isolation without any distracters present. During Steps 3 and 4, simple discrimination training was conducted using a two-stimulus array in which a distracter was present but the sample remained the same across nine trials. In Steps 5, 7, and 8, training involved a two-stimulus array conditional discrimination. Step 9 involved conditional discrimination training in which three comparison stimuli were presented and each stimulus served as a sample three times. The three samples were alternated unsystematically across the nine trials within a session. Conditional-only method. The conditionalonly condition was the same as Step 9 in the simple-conditional method. Design An adapted alternating treatments design (Sindelar, Rosenberg, & Wilson, 1985) was used to evaluate discrimination learning in both the simple-conditional and the conditional-only conditions. Stimuli were randomly assigned to two sets, and the order of conditions varied semirandomly across sessions. RESULTS AND DISCUSSION Results are presented in Figure 1. In baseline, Curtis s mean percentage of correct independent responses was 14% in the conditional-only method and 7% in the simple-conditional method. In the conditional-only method, he required prompting, and responding was variable in the first six sessions; however, he met the mastery criterion after eight sessions. During the simpleconditional method, he met the mastery criterion after 27 sessions. He did not make any errors during simple discrimination training with one stimulus (Steps 1, 2, and 6) or with one distracter present (Steps 3 and 4). During conditional discrimination training with two stimuli (Steps 5, 7, and 8), he was prompted in the first two trials. He made two errors on Steps 7 and 8, but met criterion after five and four sessions, respectively. On Step 9, he was prompted in the first two trials and met mastery criterion after three sessions. Sam did not emit any correct responses during baseline. In the conditional-only method, he required prompting and responding was variable in the first 10 sessions; however, he met the mastery criterion after 12 sessions. During the simple-conditional method, he met the mastery criterion after 24 sessions. He did not make any errors during simple discrimination training with one stimulus (Steps 1, 2, and 6). In simple discrimination trials with a distracter

4 RECEPTIVE LANGUAGE 191 Figure 1. The percentage of correct independent responses for Curtis and Sam. The numbered arrows represent the steps in the simple-conditional method. present (Steps 3 and 4), He made one error on Step 4. During conditional discrimination training with two stimuli (Steps 5, 7, and 8), prompts were delivered in the first two trials but he did not make any errors. On Step 9, he was prompted in the first two trials and made one error in the first training session, but he met the mastery criterion after three sessions. As in Grow et al. (2011, 2014) both participants learned the receptive labels more quickly with the conditional-only method. Curtis required 19 fewer sessions and Sam required 12 fewer sessions to learn the receptive labels in the conditional-only method. This may in part be a function of more steps being involved in the simple-conditional method. Nonetheless, the

5 192 JOSEPH VEDORA and KATRINA GRANDELSKI efficiency of the conditional-only method and the potential for that procedure to limit error patterns (Grow et al., 2011) may make the conditionalonly method more appealing than the simpleconditional method for practitioners who provide EIBI services to young children with autism. However, given the small number of participants, further research is needed to better understand the characteristics (e.g., age, functioning level, history with conditional discrimination training) of children for whom the conditional-only method is more efficient. Grow et al. (2011) noted issues with the development of faulty stimulus control and error patterns during the simple-conditional procedure, but these error patterns did not occur with the present participants or the participants in Grow et al. (2014). It is possible that the use of the prompt-delay procedure helped to facilitate transfer of stimulus control and prevented the development of faulty stimulus control (Green, 2001), because responses were prompted and reinforced during the first two trials of simple and conditional discrimination training with distracter stimuli. Future research might include direct comparisons between prompting procedures. It also possible that the development of faulty stimulus control is in part related to an individual s learning history. The current participants and the participants in Grow et al. (2014) were much younger than the participants in Grow et al. (2011) and had less exposure to matching-to-sample procedures used to teach auditory visual discriminations. Thus, the current participants may have contacted less reinforcement for error patterns such as win stay responses or positional biases during prior matching-to-sample tasks. Further research is required to understand the variables that affect the development of faulty stimulus control with the simple-conditional method. The present study has several limitations. First, reliability and procedural fidelity data were collected for only 13% of all sessions. Possible concerns may be mitigated by the discrete form of the response, by stimulus presentations that were predetermined and provided to the instructor, and by the high levels of reliability and procedural fidelity that were observed when it was assessed. Nonetheless, it is possible that problems with data collection or treatment implementation were not captured by observers. Second, the use of the adapted alternating treatments design may have resulted in carryover effects, in that exposure to the simple-conditional method and related reinforcement may have affected responding in the conditional-only method. The design did not permit an analysis of the independent effects of each method. The results are also limited by the small number of participants, limited number of comparative evaluations, and the lack of maintenance data. Despite these limitations, the current findings represent an independent replication of Grow et al. (2011, 2014) and extend their findings to younger participants (i.e., under the age of 3 years) who received services in the context of home-based EIBI. Thus, the results add to a growing body of literature suggesting that the conditional-only method may be preferable when teaching receptive labeling to young children with ASD. REFERENCES Green, G. (2001). Behavior analytic instruction for learners with autism: Advances in stimulus control technology. Focus on Autism and Other Developmental Disabilities, 16, Grow, L. L., Carr, J. E., Kodak, T. M., Jostad, C. M., & Kisamore, A. N. (2011). A comparison of methods for teaching receptive labeling to children with autism spectrum disorders. Journal of Applied Behavior Analysis, 44, doi: /jaba Grow, L. L., Kodak, T. M., & Carr, J. E. (2014). A comparison of methods for teaching receptive labeling to children with autism spectrum disorders: A systematic replication. Journal of Applied Behavior Analysis, 47, doi: /jaba.141 Lovaas, O. I. (2003). Teaching individuals with developmental delays: Basic intervention techniques. Austin, TX: Pro-Ed. Love, J. R., Carr, J. E., Almason, S. M., & Petursdottir, A. I. (2009). Early and intensive behavioral intervention for autism: A survey of clinical practices. Research in Autism

6 RECEPTIVE LANGUAGE 193 Spectrum Disorders, 3, doi: /j. rasd Sindelar, P. T., Rosenberg, M. S., & Wilson, R. J. (1985). An adapted alternating treatments design for instructional research. Education and Treatment of Children, 8, Wallace, K. S., & Rogers, S. J. (2010). Intervening in infancy: Implications for autism spectrum disorders. Journal of Child Psychology and Psychiatry, 51, doi: /j x Received January 16, 2014 Final acceptance June 23, 2014 Action Editor, Anna Petursdottir