McKearney J W
J Exp Anal Behav. 1970 Sep;14(2):167-75. doi: 10.1901/jeab.1970.14-167.
Food-deprived pigeons responded under a 10-min fixed-interval schedule of food presentation. During even-numbered minutes of the schedule, the discriminative stimuli were the same as those present when food was delivered. During odd-numbered minutes there was either a change in keylight color or a change in overhead illumination, either for the entire duration of the odd-numbered minutes, or for 3-sec after each response. Responding during even-numbered minutes showed the usual pattern of positive acceleration; responding during odd-numbered minutes was similarly graded, but rates were much lower. The response-rate-increasing effects of amobarbital were inversely related to control rates of responding for both even- and odd-numbered minutes. However, when the stimulus change during odd-numbered minutes was either keylight color or a change from a darkened to a brightly illuminated chamber, increases in responding were considerably less than predicted on the basis of the effects on responding during even-numbered minutes. When the stimulus change was from a darkened to a dimly illuminated chamber, control rates of responding changed little, but increases in responding during odd-numbered minutes after amobarbital were considerably greater, and of the approximate order expected on the basis of control rate.
食物被剥夺的鸽子在10分钟固定间隔的食物呈现时间表下做出反应。在时间表的偶数分钟内，辨别性刺激与食物递送时出现的刺激相同。在奇数分钟内，要么按键灯颜色发生变化，要么头顶照明发生变化，变化持续整个奇数分钟，或者在每次反应后持续3秒。在偶数分钟内的反应呈现出通常的正加速模式；在奇数分钟内的反应也有类似的分级，但速率要低得多。异戊巴比妥对反应速率的增加作用与偶数和奇数分钟的对照反应速率呈负相关。然而，当奇数分钟内的刺激变化是按键灯颜色变化或从黑暗的实验箱变为明亮照明的实验箱时，反应增加量比根据其对偶数分钟内反应的影响所预测的要少得多。当刺激变化是从黑暗的实验箱变为昏暗照明的实验箱时，对照反应速率变化不大，但异戊巴比妥给药后奇数分钟内的反应增加量要大得多，且大致符合基于对照速率预期的量级。
