Additivity of resurgence and spontaneous recovery.

Resurgence and spontaneous recovery are two extensively studied behavioral phenomena in which previously extinguished operant behavior increases or reemerges. These findings are relevant to understanding flexibility in behavior but also relapse. Resurgence is the re-return of an extinguished target response (R1) when reinforcement conditions worsen for a more recently reinforced alternative response (R2), such as with extinction. Spontaneous recovery is the return of an eliminated R1 following time off from experiencing extinction conditions, such as with a retention interval. The present experiment examined whether combining tests for resurgence (removing R2 reinforcement) and spontaneous recovery (retention interval) produced greater increases in R1 than either test in isolation. University students played a computer video game and learned to perform R1 during Phase 1. During Phase 2, R1 was placed on extinction while simultaneously performing R2 was reinforced (Ext + DRA). Finally, the four groups of participants were tested for (1) neither resurgence or spontaneous recovery, (2) only resurgence, (3) only spontaneous recovery, or (4) both resurgence and spontaneous recovery. Increases in R1 were additive, with combined testing producing significantly greater responding that either of the two tests in isolation. We discuss theoretical issues as well as the implications of our findings for the treatment and relapse of challenging behavior.