Incubation of anxiety and instrumental behavior.

Abstract

Two studies investigated disruptive effects of conditioned fear stimuli upon instrumental [rat] behavior, in relation to time following fear training. Conditioned suppression of bar pressing showed the CS [conditioned stimulus] to become progressively more disruptive of bar pressing over time, following both conditioned-avoidance and fixed-duration CS-US [unconditioned stimulus] training. Also, allowing fear to incubate resulted in poorer learning of escape from conditioned fear stimuli. The data were interpreted as providing support for Denny and Ditchman''s (1962) explanation of the performance decrement, known as the Kamin effect, which appears in the retention of an incompletely learned avoidance response.