AN ANALYSIS OF REINFORCER SUBSTITUTABILITY USING OBJECT MANIPULATION AND SELF-INJURY AS COMPETING RESPONSES

The concept of reinforcer substitutability proposes a continuum of int eractions among reinforcers in a given situation. At one end of this c ontinuum, reinforcers are substitutable, with one reinforcer being rea dily traded for another. We conducted an analysis of reinforcers that were substitutable with those produced by self-injurious behavior (SIB ). Three individuals with profound developmental disabilities, whose S IB appeared to be maintained by automatic reinforcement, participated. Results of three experiments showed that (a) object manipulation and SIB were inversely related when leisure materials and SIB were concurr ently available, with participants showing almost complete preference for object manipulation; (b) attempts to reduce SIB using the preferre d objects as reinforcers in differential reinforcement contingencies w ere unsuccessful for all 3 participants; and (c) participants' prefere nces for SIB or object manipulation systematically changed when reinfo rcer cost (the amount of effort required to obtain the object) was var ied. Results of the three experiments illustrate the importance of exa mining interactions among concurrently available reinforcers when cond ucting reinforcer assessments.