Influence of Three Stimulus Conditions upon the Strength of a Secondary Reinforcement Effect

Abstract

Animals were trained to approach a water dipper at the onset of a light and a tone, water being received following approach on an intermittent schedule. For three groups of animals bar-pressing was then reinforced on an intermittent schedule, using three stimulus conditions: light and tone only; light, tone, and dry dipper; and light, tone, and interrupted presentation of dry dipper. The interrupted presentation proved to be the most effective reinforcer. Ss in other groups which did not at first show a strong effect did so when switched to this condition.