The role of stimulus combinations in the repeated assessment of resurgence.

The current study examined the role of stimulus combinations on the repeated assessment of resurgence. Using a within-session resurgence procedure, rats were exposed to different conditions, each with distinct stimulus combinations (AAA, ABA, ABB, ABC and AAB). Two arrangements of stimulus changes were compared: Experiment 1 involved changes in stimulus combinations every five sessions, while Experiment 2 implemented changes every session. Resurgence was observed in both experiments; however, Experiment 2 demonstrated more consistent and repeated resurgence when stimulus combinations changed every session. Notably, the ABA, ABB and ABC conditions showed the highest percentage of sessions in which resurgence was observed. Lastly, the current study extends the application of the within-session resurgence procedure to rats and auditory stimuli, providing a reliable method for assessing resurgence in single subjects under different variable conditions.

Effects of delay of reinforcement on ABA renewal.

ABA renewal was assessed by decreasing response rates by means of extinction or a 12-s delay of reinforcement in one experiment with rats. In a first phase, rats were trained to lever press for water in Context A. Rats were exposed to a second phase in Context B, where lever-pressing decreased for all rats; for one group of rats, lever-pressing decreased by means of extinction, while lever-pressing decreased by means of a 12-s delay for the other group. During a third phase, both groups were once again exposed to Context A with no reinforcer deliveries for lever-pressing. Once rats were exposed to the latter phase, renewal was observed for both groups. Results suggest that delay of reinforcement can be used as an alternative procedure to help reduce behavior and mitigate relapse.