Effects of increased response effort and reinforcer delay on choice and aberrant behavior.

A four-phase investigation was completed to analyze the utility of forced-choice preference assessments when response effort and reinforcer delays are altered within a subsequent reinforcer assessment. The results indicated that access to highly preferred stimuli continued to serve as a reinforcer when increased response effort was required. When reinforcer delay was increased, the utility of preferred stimuli to serve as a reinforcer was variable. Despite stimuli continuing to serve as reinforcers for academic task engagement, increased response effort and reinforcer delay resulted in an increased level of aberrant behavior.