Grings W W, Givens M C, Carey C A
J Exp Psychol Gen. 1979 Sep;108(3):281-95. doi: 10.1037//0096-3445.108.3.281.
Three experiments observed differential electrodermal responding to signal stimuli (CSs) by contrasting positive, random, and negative contingencies between the signals and strong stimuli (UCSs). Experimentation began as a test of the proposition that electrodermal response to a random signal (or CSR) would lie between the response to a reinforced or excitatory stimulus (CS+) and that to a nonreinforced or inhibitory stimulus (CS- or CSI). A clear intermediate position for CSR did not result. Instead it appeared that CSR was operating as a mildly excitatory signal. This led to a second experiment where response to pairs of stimuli with different contingent relations could be compared in independent samples. The pairs were CS+ and CS-, CS+ and CSR, and CSR and CS-. Differential responding was observed in all pairs and response to CSR was significantly larger in the group receiving CSR with CS- than it was in the group receiving CSR with CS+. A contingency contrast effect was suggested. A third experiment explored the implications of a contingency contrast effect by varying overall UCS density, the duration of "safety intervals," and the presence or absence of instructions about contingencies. The UCS density and instruction variables influenced the differential performance to CSR and CS-, a result that was interpreted as further evidence for a perceptual contingency-contrast effect. Some theoretical implications of such a contrast phenomenon are examined, as they apply to autonomic learning. The CS is interpreted as a signal supplying contingency information that is dependent upon a complex of factors in the stimulation environment.
三项实验通过对比信号与强刺激（无条件刺激，UCSs）之间的正性、随机和负性关联，观察了对信号刺激（条件刺激，CSs）的不同皮肤电反应。实验最初是为了检验一个命题，即对随机信号（或CSR）的皮肤电反应介于对强化或兴奋性刺激（CS+）和对非强化或抑制性刺激（CS-或CSI）的反应之间。CSR并没有呈现出明显的中间位置。相反，CSR似乎起到了轻度兴奋性信号的作用。这导致了第二项实验，在该实验中，可以在独立样本中比较对具有不同关联关系的刺激对的反应。这些刺激对包括CS+和CS-、CS+和CSR以及CSR和CS-。在所有刺激对中都观察到了差异反应，并且在接受CSR与CS-配对的组中，对CSR的反应明显大于接受CSR与CS+配对的组。这表明存在一种关联对比效应。第三项实验通过改变总体UCS密度、“安全间隔”的持续时间以及是否有关于关联的指示，探讨了关联对比效应的影响。UCS密度和指示变量影响了对CSR和CS-的差异表现，这一结果被解释为对感知关联对比效应的进一步证据。本文研究了这种对比现象在自主学习方面的一些理论意义。条件刺激（CS）被解释为一种提供关联信息的信号，该信号依赖于刺激环境中的一系列复杂因素。
