Repeated, within-session resurgence.

Resurgence is a reliable, transient effect that only occasionally is replicated more than once within a single experiment or subject. In the present experiments, within-session resurgence was generated repeatedly by dividing individual sessions into three phases (Training, Alternative-Reinforcement, and Resurgence-Test). In Experiments 1 and 2, resurgence reliably occurred in most of the 22-30 daily sessions when responding was reinforced on, respectively, fixed- and variable-interval schedules. Resurgence magnitude and duration did decrease across replications for some subjects, but not for others. To examine the utility of the procedure in studying the effects of an independent variable on resurgence, in Experiment 3 the effects of rich and lean baseline and alternative reinforcement rates on resurgence were compared. The target response was eliminated more rapidly, resurgence occurred more often, and usually was greater following rich alternative reinforcement rates. Resurgence was of greater magnitude when the baseline reinforcement rate was relatively lean compared to the alternative reinforcement rate. These experiments provide a reliable method for generating resurgence within individual sessions, instead of across multiple-session conditions, that can be repeated over many successive sessions.