The transformation of stimulus functions is said to occur when the functions of one stimulus alter or transform the functions of another stimulus in accordance with the derived relation between the two, without additional training. This effect has been demonstrated with a number of derived stimulus relations, behavioral functions, experimental preparations, and subject populations. The present paper reviews much of the existing research on the transformation of stimulus functions and outlines a number of important methodological and conceptual issues that warrant further attention. We conclude by advocating the adoption of the generic terminology of relational frame theory to describe both the derived transformation of stimulus functions and relational responding more generally.

Every article on stimulus equivalence or derived stimulus relations published in the Journal of Applied Behavior Analysis was evaluated in terms of characteristics that are relevant to the development of applied technologies: the type of participants, settings, procedure (automated vs. tabletop), stimuli, and stimulus sensory modality; types of relations targeted and emergent skills demonstrated by participants; and presence versus absence of evaluation of generalization and maintenance. In most respects, published reports suggested the possibility of applied technologies but left the difficult work of technology development to future investigations, suggestions for which are provided.

The function of perseverative speech for an adult man who had been diagnosed with autism and mental retardation was examined. Results showed that verbal perseverations were maintained by social attention. An intervention consisting of differential reinforcement of appropriate verbal responses and extinction of perseverative verbal responding was effective in decreasing verbal perseverations.

The effectiveness of a behavioral skills training (BST) package to teach the implementation of the first three phases of the picture exchange communication system (PECS) was evaluated with 3 adults who had no history teaching any functional communication system. A multiple baseline design across participants was used to evaluate the effectiveness of the training package, which consisted of a video, written and verbal instructions, modeling, rehearsal, and feedback. Results showed significant improvements relative to baseline in a short amount of training time and that skills generalized to a learner with a severe developmental disability. Skills were maintained at 1 month follow-up for 1 participant.

Perspective-taking, or the ability to demonstrate awareness of informational states in oneself and in others, has been of recent interest in behavioral psychology. This is, in part, a result of a modern behavioral approach to human language and cognition known as Relational Frame Theory, which views perspectivetaking as generalized operant behavior based upon a history of reinforcement for relational responding . Previous lines of research have developed a behavioral protocol for assessing relational learning deficits in perspective-taking and have implicated the lack of perspective-taking as a basis for the social deficits observed in children with autism. However, no empirical investigations have been conducted on relational learning deficits in perspective-taking with autistic populations. The present paper reports 2 experiments that investigated whether children with autism spectrum disorder demonstrated relational learning deficits in a perspective-taking task as compared to their age-matched typicalill developing peers. We also investigated whether accuracy in perspective-taking correlated with scores on standardized instruments commonly used in the assessment of autism spectrum disorder, and whether relational responding in perspective-taking improves following a history of reinforcement for such responding . Results of Experiment 1 demonstrated statistically significant differences in errors as a function of type of relation , while visual inspection revealed that partiCipants with autism spectrum disorder made more errors than typically developing children on 2 of the 3 types of relations examined. Results of Experiment 2 illustrated that a history of reinforced relational responding improved performance on the perspective-taking task.