Bouton M E, Rosengard C, Achenbach G G, Peck C A, Brooks D C
Department of Psychology, University of Vermont, Burlington 05405.
Q J Exp Psychol B. 1993 Feb;46(1):63-95.
Four experiments with rat subjects examined the effects of contextual conditioning on conditioned appetitive performance. Experiment 1 compared the effects of contextual conditioning on performance to conditioned stimuli (CSs) with different conditioning histories. Contextual conditioning enhanced performance to the CS if the CS had first been conditioned and then extinguished, but had no effect on performance when the CS had been merely paired or unpaired with food. Experiments 2 and 3 then asked whether the effect on the extinguished CS was due to contextual conditioning acting as a cue for conditioning. In Experiment 2, extinction procedures in which extra unconditioned stimuli (USs) were presented during the intertrial intervals were found to reduce the CS's sensitivity to enhancement by contextual conditioning, but had no effect on spontaneous recovery. In Experiment 3, USs added to conditioning or extinction acquired the ability to cue the corresponding performance. Under some conditions, USs added to conditioning could suppress performance (Experiment 4). The results suggest that contextual conditioning has complex effects that can be better understood by recognizing that contextual conditioning, as well as the USs that create it, may acquire discriminative control over conditioned responding.
四项以大鼠为实验对象的实验研究了情境条件作用对条件性食欲行为表现的影响。实验1比较了情境条件作用对具有不同条件作用历史的条件刺激（CSs）行为表现的影响。如果CS首先经过条件作用然后消退，情境条件作用会增强对CS的行为表现，但当CS仅仅与食物配对或未配对时，情境条件作用对行为表现没有影响。实验2和实验3接着探讨了对消退后的CS的影响是否是由于情境条件作用作为一种条件作用线索。在实验2中，发现在试验间隔期间呈现额外无条件刺激（USs）的消退程序会降低CS对情境条件作用增强的敏感性，但对自发恢复没有影响。在实验3中，添加到条件作用或消退过程中的USs获得了提示相应行为表现的能力。在某些条件下，添加到条件作用中的USs可以抑制行为表现（实验4）。结果表明，情境条件作用具有复杂的影响，通过认识到情境条件作用以及产生它的USs可能获得对条件反应的辨别性控制，可以更好地理解这些影响。
