J Exp Anal Behav. 1969 Mar;12(2):239-46. doi: 10.1901/jeab.1969.12-239.
The key pecks of four pigeons were reinforced on a variable-interval 5-min schedule which operated in each of the four components of a multiple schedule, indicated by red, green, yellow, and blue stimuli and presented in such an order that the red stimulus always preceded the yellow and the green stimulus always preceded the blue. After establishing baseline rates, the reinforcement schedule associated with the blue and yellow components was altered so that one was now an extinction schedule and the other was a variable-interval 1-min schedule. In a second experimental stage, the blue stimulus was interchanged with the yellow so that the red stimulus preceded the blue and the green stimulus preceded the yellow. In both experimental stages the response rate in the variable-interval 5-min component that preceded the extinction component was higher than the response rate in the variable-interval 5-min component that preceded the variable-interval 1-min component. The results were discussed in relation to the importance of stimulus ordering in experiments concerned with investigating behavioral contrast.
四只鸽子的关键啄食行为在一个多重时间表的四个部分中的每一个部分都受到强化，这四个部分由红色、绿色、黄色和蓝色刺激物表示，并按照红色刺激物总是先于黄色刺激物，绿色刺激物总是先于蓝色刺激物的顺序呈现。在建立基线速率后，与蓝色和黄色部分相关的强化计划发生了变化，一个现在是消光计划，另一个是可变间隔 1 分钟计划。在第二实验阶段，蓝色刺激物与黄色刺激物交换，使得红色刺激物先于蓝色刺激物，绿色刺激物先于黄色刺激物。在两个实验阶段中，在消光成分之前的可变间隔 5 分钟成分中的反应率都高于在可变间隔 1 分钟成分之前的可变间隔 5 分钟成分中的反应率。结果与在调查行为对比的实验中刺激顺序的重要性有关。
