Bouton M E, Kenney F A, Rosengard C
Department of Psychology, University of Vermont, Burlington 05405.
Behav Neurosci. 1990 Feb;104(1):44-55. doi: 10.1037//0735-7044.104.1.44.
Four experiments with rats were run to investigate whether fear extinction conducted under the influence of a benzodiazepine transfers to the undrugged state. Fear was conditioned by pairing an experimental chamber with footshock and was assessed by observing freezing, a characteristic response of the rat to stimuli associated with shock. In Experiment 1, extinction of the chamber cues under chlordiazepoxide (librium) or diazepam (valium) was compared with extinction under a placebo; both drugs interfered with extinction in a dose-dependent manner as indicated by freezing during an undrugged test. Further results with chlordiazepoxide suggested that the effect depended on the drug's specific combination with extinction and that it occurred even though the extinction procedure otherwise eliminated fear completely (Experiment 2). Repeated preexposure to the drug, and the development of partial tolerance to its sedative effects, did not weaken the interference effect (Experiment 3). Other evidence suggested that the drug signaled or retrieved extinction instead of disrupting learning or consolidation (Experiment 4). The results are consistent with research suggesting that extinguished fear can be "renewed" if the exteroceptive contextual stimuli are changed after extinction. Extinction combined with either unique exteroceptive or interoceptive cues may be specific to its context.
进行了四项以大鼠为对象的实验，以研究在苯二氮䓬类药物影响下进行的恐惧消退是否会转移到未用药状态。通过将实验箱与足部电击配对来建立恐惧条件反射，并通过观察僵立反应（大鼠对与电击相关的刺激的特征性反应）来评估恐惧。在实验1中，比较了在氯氮䓬（利眠宁）或地西泮（安定）作用下实验箱线索的消退情况与安慰剂作用下的消退情况；在未用药测试期间，两种药物均以剂量依赖的方式干扰消退，这由僵立反应表明。氯氮䓬的进一步实验结果表明，这种影响取决于药物与消退的特定组合，并且即使消退程序在其他方面完全消除了恐惧，这种影响仍然会发生（实验2）。反复预先接触药物以及对其镇静作用产生部分耐受性，并未削弱干扰作用（实验3）。其他证据表明，药物是发出消退信号或恢复消退，而不是破坏学习或巩固（实验4）。这些结果与研究结果一致，即如果在消退后改变外部感受性情境刺激，消退的恐惧可能会“重新出现”。与独特的外部感受性或内部感受性线索相结合的消退可能特定于其情境。
