Effects of concurrent random-time schedules on the spatial distribution of behavior in rats

We evaluated the effects of concurrent random temporal contingencies of water delivery on the location of rats' behavior. In this experiment, two concurrent random-time schedules delivered water in two dispensers that were located at opposite ends of the chamber, and provided complementary frequencies of water deliveries while the overall number of deliveries stayed constant. Time allocation in the areas adjacent to each water dispenser covaried with water deliveries, although no proportional relation was found. Rats showed a preference for the area where water was initially presented. The results point to the importance of examining spatial properties and patterning of behavior.