Attack induced by second-order schedules of reinforcement

Abstract

Food-deprived pigeons were exposed to tandem, chain, and brief-stimulus second-order schedules in which the completion of three 80-sec fixed-interval components was followed by food delivery. Two birds attacked a nearby stuffed pigeon shortly after the presentation of either food-paired or food-nonpaired visual stimuli, as well as following food. The third subject exhibited predominantly postfood attack. These results suggest that the locus of schedule-induced attack can be controlled by a stimulus event, whether food delivery or key-color change, that reliably precedes a relatively long period of food unavailability.