Abstract
Efficient methods for assessing the relative aversiveness of stimuli are sparse and underresearched. Having access to efficient procedures that can identify aversive stimuli would benefit researchers and practitioners alike. Across three experiments, 13 participants helped to pilot, refine, and test two approaches to identifying negative reinforcers. The first experiment presented two conditions, one in which computerized button pressing started or stopped one of two recorded infant cries (or silence, when the control button was selected). Choices were presented either in a modified observing-response procedure (i.e., simultaneous observing) or in a modified progressive-ratio procedure (i.e., committed concurrent progressive ratio; CCPR). Results were favorable though not conclusive on their own. A second experiment, using more distinct stimuli (i.e., one likely aversive, one likely not aversive), replicated the first, and clearer results emerged. Finally, the third experiment tested the stimuli from the second experiment in a CCPR arrangement where sound was terminated contingent on responding and idiosyncratic negative reinforcement hierarchies emerged. The utility of these two procedures is discussed, and future work that addresses the limitations is outlined.