Picker M, Leibold L, Endsley B, Poling A
J Pharmacol Exp Ther. 1986 Aug;238(2):529-35.
The effects of the anticonvulsant drugs valproic acid, phenytoin, phenobarbital and diazepam were examined in pigeons performing under a fixed-consecutive-number schedule with and without an added external discriminative stimulus. Under these schedules, a reinforced response run consisted of responding between eight and 12 times on one response key (work key) and then responding once on a second response key (reinforced key). For one group of pigeons, an external discriminative stimulus signaled completion of the response requirement on the work key, whereas no stimulus change was programmed for the other group. Phenobarbital (5-60 mg/kg) and diazepam (0.5-6 mg/kg) produced large decreases in reinforced response runs (accuracy) and rates of responding. The magnitude of these accuracy- and rate-decreasing effects was larger in the group without the external discriminative stimulus. Under both schedules, these drugs produced pronounced increases in the probability of switching to the reinforcement key before completion of the minimal response requirement on the work key. Valproic acid (20-160 mg/kg) and phenytoin (1.25-10 mg/kg) also decreased both accuracy and rates of responding. Although the accuracy-decreasing effects of these drugs were relatively small in magnitude, they were consistently larger in the group without the external discriminative stimulus. These data suggest that the addition of an external discriminative stimulus attenuates the disruptive behavioral effects of anticonvulsant drugs.
在有或没有额外外部辨别性刺激的固定连续数强化程序下，对鸽子进行实验，研究抗惊厥药物丙戊酸、苯妥英、苯巴比妥和地西泮的作用。在这些强化程序中，一次强化反应序列包括在一个反应键（工作键）上进行8至12次反应，然后在第二个反应键（强化键）上进行一次反应。对于一组鸽子，外部辨别性刺激表示工作键上的反应要求已完成，而另一组则未设置刺激变化。苯巴比妥（5 - 60毫克/千克）和地西泮（0.5 - 6毫克/千克）使强化反应序列（准确性）和反应率大幅下降。在没有外部辨别性刺激的组中，这些准确性和反应率下降效应的幅度更大。在两种强化程序下，这些药物都使在工作键上完成最小反应要求之前切换到强化键的概率显著增加。丙戊酸（20 - 160毫克/千克）和苯妥英（1.25 - 10毫克/千克）也降低了反应的准确性和速率。尽管这些药物的准确性下降效应幅度相对较小，但在没有外部辨别性刺激的组中始终更大。这些数据表明，添加外部辨别性刺激可减弱抗惊厥药物的行为干扰作用。
