A replication of preference displacement research in children with autism spectrum disorder

Single- vs. combined-category preference assessments for edible, leisure, and social-interaction stimuli

A concern when conducting combined-category preference assessments is the potential for displacement effects, a shift in the preference ranking from highly preferred to moderately or less preferred for stimuli in two of three stimulus categories (e.g., edible, leisure, or social-interaction). In this study, we evaluated potential displacement effects in combined-category arrays of edible, leisure, and social-interaction stimuli for five individuals with autism. First, single-category paired-stimulus preference assessments were implemented to identify two highly preferred stimuli from each category. When these stimuli were included in a combined-category preference assessment, displacement effects were observed for three of five participants. During a subsequent reinforcer assessment, stimuli identified as less preferred in the combined-category preference assessment functioned as reinforcers for two participants. Additionally, although social interaction was not identified as highly preferred for three of the five participants, it functioned as a reinforcer for four participants.

Evaluating the effects of social interaction on the results of preference assessments for leisure items

A variable that may influence the outcomes of stimulus preference assessments (SPAs) is whether social interaction is provided during the stimulus access period. In Experiment 1, we compared the outcomes of a Solitary paired stimulus preference assessment (PSPA) (toys only), Social PSPA (toys plus social interaction), and Combined PSPA (toys alone and toys plus social interaction) to determine whether the addition of social interaction influenced preference for toys in preschool children. In Experiment 2, we conducted a concurrent-operant reinforcer assessment to compare the reinforcing efficacy of stimuli with and without social interaction. Experiment 1 showed preference for toys was stable across assessments (Solitary and Social PSPAs) and most participants preferred toys plus social interaction when compared in a single assessment (Combined PSPA). Experiment 2 showed that results of the Combined PSPA in Experiment 1 predicted the outcome of most participants' reinforcer assessments.