A test for both positive and negative response summation in the pigeon

Abstract

Four pigeons were trained to keypeck on a multiple variable interval-extinction schedule, in which different composite stimuli were associated with the variable interval and extinction schedules. The six composite stimuli used were compounds of houselight (on or off) and form (horizontal line, vertical line, or cross) on the response key. Composite stimuli were constructed in such a way that some components of houselight or form were more frequently associated with reinforcement or extinction. It was found that the composite stimulus formed of components most frequently associated with extinction controlled a lower response rate than other composite stimuli associated with extinction. However, the composite stimulus formed of components most frequently associated with reinforcement did not control a higher response rate than other reinforced stimuli.