Hugdahl K, Ohman A
J Exp Psychol Hum Learn. 1977 Sep;3(5):608-18.
In the present study we examined the hypothesis that electrodermal responses conditioned to fear-relevant stimuli are insensitive to verbal instructions. In the first experiment, different groups of subjects were conditioned to fear-relevant and fear-irrelevant control stimuli in a long interstimulus interval differential paradigm with shock as the unconditioned stimulus. Then half of the subjects were informed that no more shocks would be presented, and a number of extinction trials followed. The instruction completely abolished responding to fear-irrelevant stimuli, while leaving responses to the fear-relevant stimuli unaffected. In the second experiment, subjects were "conditioned" to fear-relevant or irrelevant stimuli by an instruction involving threat of shock. This manipulation potentiated potentiated responses to fear-relevant stimuli significantly more than responses to fear-irrelevant stimuli. Thus, instruction had a symmetrical effect on acquisition and extinction to fear-irrelevant stimuli, whereas it facilitated acquisition but was ineffective in reducing responding to the other class of stimuli. These results are related to a preparedness theory, and their relevance for an understanding of phobias is discussed.
在本研究中，我们检验了这样一种假设：与恐惧相关的刺激所引发的皮肤电反应对言语指令不敏感。在第一个实验中，不同组的受试者在以电击作为无条件刺激的长刺激间隔差异范式中，接受与恐惧相关和与恐惧无关的对照刺激的条件作用。然后，一半的受试者被告知不会再有电击出现，随后进行了多次消退试验。该指令完全消除了对与恐惧无关刺激的反应，而对与恐惧相关刺激的反应没有影响。在第二个实验中，通过涉及电击威胁的指令使受试者“条件化”于与恐惧相关或无关的刺激。这种操作使对与恐惧相关刺激的反应增强的程度明显大于对与恐惧无关刺激的反应。因此，指令对与恐惧无关刺激的习得和消退具有对称效应，而它促进了习得，但在减少对另一类刺激的反应方面无效。这些结果与一种准备理论相关，并讨论了它们对于理解恐惧症的相关性。
