Holland P C
J Exp Psychol Anim Behav Process. 1984 Oct;10(4):461-75.
Two experiments using a conditioned suppression procedure with rat subjects found that postconditioning reinforcement of an inhibitory feature stimulus (X) had substantially different effects depending on whether a serial (A+, X----A-) or a simultaneous (A+, AX-) feature negative discrimination procedure was used to establish the inhibition. With the simultaneous procedure, acquisition of excitation to the previously inhibitory X was retarded when X was paired with shock. Subsequent summation tests showed no evidence of inhibition to X after reinforced X presentations. However, acquisition of excitation to X was unaffected by prior serial feature negative training, and X-shock pairings had relatively little effect on X's inhibitory power in summation tests. These data suggest that the nature of inhibition established in feature negative discriminations differs substantially depending on the temporal arrangement of stimuli. One possibility is that inhibitors established using simultaneous stimulus arrangements modulate behavior by acting on a representation of the unconditioned stimulus, but inhibitors established with serial procedures act on particular conditioned stimulus-unconditioned stimulus associations.
两项以大鼠为实验对象、采用条件性抑制程序的实验发现，对抑制性特征刺激（X）进行条件作用后的强化，其效果在很大程度上取决于建立抑制时采用的是序列式（A+，X----A-）还是同时式（A+，AX-）特征性负性辨别程序。在同时式程序中，当X与电击配对时，对先前具有抑制作用的X的兴奋习得受到阻碍。随后的总和测试表明，在强化呈现X后，没有证据显示对X存在抑制作用。然而，对X的兴奋习得不受先前序列式特征性负性训练的影响，并且在总和测试中，X与电击的配对对X的抑制能力影响相对较小。这些数据表明，特征性负性辨别中建立的抑制性质会因刺激的时间安排而有很大差异。一种可能性是，采用同时性刺激安排建立的抑制剂通过作用于无条件刺激的表征来调节行为，但采用序列式程序建立的抑制剂作用于特定的条件刺激 - 无条件刺激关联。
