An evaluation of resurgence in mice

Abstract

Owing in part to the implications of resurgence for issues surrounding human health and adaptive problem solving, a substantial amount of laboratory research has been dedicated to understanding why this form of relapse occurs and what factors affect it. This research, however, has never been extended to mice, leaving unknown the specific experimental parameters that are appropriate for studying resurgence in this species. Two experiments were conducted in which mice were exposed to a three-phase resurgence preparation in a multiple-baseline-across-subjects design. In Phase 1, pressing a target lever produced food according to a variable-interval 15-s schedule. In Phase 2, target-lever pressing was extinguished, and nose poking produced reinforcement according to either a variable-interval 15-s (Experiment 1) or fixed-ratio 1 (Experiment 2) schedule. Finally, alternative reinforcement was suspended to test for resurgence. Lever pressing relapsed for one of four mice in Experiment 1, but all four mice demonstrated relapse in Experiment 2. Thus, relatively dense schedules of alternative reinforcement may be required to reliably study resurgence of previously reinforced responding in mice. These findings are instructive for researchers who are interested in studying resurgence of mice’s behavior and further demonstrate the cross-species generality of this form of relapse.