1) The recurrence of the rate of a response that had been reduced when aversive stimuli no longer are present or delivered contingent on the response.

2) Return to an earlier level of responding after responding has been reduced by an operation such as extinction or punishment. The vocabulary does not distinguish between recovery during maintained conditions and recovery after the conditions have been discontinued (e.g., recovery during punishment refers to a return of responding toward prepunishment levels while punishment continues, whereas recovery after punishment refers to a return toward those levels after punishment is discontinued).