Branch M N, Dearing M E
Pharmacol Biochem Behav. 1982 May;16(5):713-8. doi: 10.1016/0091-3057(82)90223-4.
Food deprived pigeons were trained under a procedure in which trials began with the transillumination of one of three keys by red or green light. Pecking this key extinguished the light behind it and, after a variable delay (0.05, 0.5, 1.0, 2.0, or 4.0 sec), was followed by illumination of the two other keys, one by red light and one by green. Pecks on the key that was the same color as the previously illuminated key could produce access to food. High levels of accuracy were obtained at all delays. The acute and chronic effects of cocaine on performance generated by this procedure (delayed-matching-to-sample) were studied. Acutely, cocaine (0.56-10.0 mg/kg) produced dose-related decreases in accuracy and in rate of completing trials. Accuracy at the longest delay was more sensitive to cocaine's effects. Daily administration of a comparatively large dose (5.6 mg/kg) resulted in tolerance to the rate-reducing and accuracy-reducing effects of large doses.
对食物匮乏的鸽子进行训练，训练过程如下：每次试验开始时，三个按键中的一个会被红灯或绿灯透射照明。啄这个按键会熄灭其后面的灯光，经过一段可变延迟（0.05、0.5、1.0、2.0或4.0秒）后，另外两个按键会亮起，一个是红灯，一个是绿灯。啄与之前亮起的按键颜色相同的按键可以获得食物。在所有延迟条件下都获得了较高的准确率。研究了可卡因对该程序（延迟匹配样本）产生的行为表现的急性和慢性影响。急性给药时，可卡因（0.56 - 10.0毫克/千克）会导致准确率和完成试验的速率出现剂量相关的下降。在最长延迟条件下的准确率对可卡因的影响更敏感。每日给予相对大剂量（5.6毫克/千克）会导致对大剂量可卡因降低速率和准确率的效应产生耐受性。
