Yarczower M
J Exp Anal Behav. 1971 Jul;16(1):89-94. doi: 10.1901/jeab.1971.16-89.
Pigeons were used to assess stimulus control during the development of a conditional discrimination. The training consisted of three stages. In Stage 1, key pecks were reinforced in the presence of a white line tilted 40 degrees to the right of vertical on a green background and non-reinforced when the same line appeared on a red background. In Stage 2, key pecks were reinforced when a white vertical line appeared on a red background and were non-reinforced in the presence of a 40 degrees slanted line on a red background. In Stage 3, key pecks were reinforced in the presence of the green background regardless of the line tilt, but were differentially reinforced in the presence of the red background (as in Stage 2). Generalization tests were conducted after each stage of training and consisted of five white lines on backgrounds that were green, red, or dark. The effects of the differential reinforcement contingencies on control by line orientation were restricted to the condition in which the red light appeared and resulted in behavioral control that could be characterized as: if red, pay closer attention to line tilt than if not red.
在条件性辨别发展过程中，鸽子被用于评估刺激控制。训练包括三个阶段。在第一阶段，当一条白色线条在绿色背景上向垂直方向右侧倾斜40度时，啄键行为得到强化；当同一条线条出现在红色背景上时，啄键行为不被强化。在第二阶段，当一条白色垂直线条出现在红色背景上时，啄键行为得到强化；当一条40度倾斜的线条出现在红色背景上时，啄键行为不被强化。在第三阶段，无论线条倾斜情况如何，当绿色背景出现时，啄键行为得到强化，但在红色背景出现时（如第二阶段），啄键行为得到差别强化。在每个训练阶段之后进行泛化测试，测试由五条白色线条组成，背景分别为绿色、红色或黑色。差别强化偶然性对线条方向控制的影响仅限于红灯出现的条件，并且导致了可以被描述为：如果是红色，比不是红色时更关注线条倾斜的行为控制。
