Abstract
Differential reinforcement of other behavior (DRO) and noncontingent reinforcement were compared as control procedures during the modification of a 3-yr-old preschooler's compliance. The recorded reinforcer was teacher proximity (within 3 ft (0.9) of the subject for at least 5 sec) which was often accompanied by positive verbal comments that varied in content across experimental conditions. The verabal content during contingent reinforcement might have been: "Thank you for picking up the blocks"; during non-contingent reinforcement: "You're wearing a pretty dress"; and during DRO: "I don't blame you for not picking up because it isn't any fun". Contingent reinforcement increased compliance in all manipulation conditions. Noncontingent reinforcement decreased compliance during two reversal conditions. However, the behavior was variable and did not decrease to the low levels reached during the two DRO reversals.