Vervliet Bram, Vansteenwegen Debora, Baeyens Frank, Hermans Dirk, Eelen Paul
Centre for the Psychology of Learning and Behaviour Therapy, Department of Psychology, University of Leuven, Tiensestraat 102, B-3000 Leuven, Belgium.
Behav Res Ther. 2005 Mar;43(3):357-71. doi: 10.1016/j.brat.2004.02.005.
In a human fear conditioning experiment, 32 participants were trained in a differential conditioning procedure with geometrical shapes as CS+ and CS- (four presentations each), and an electric shock as US. Measures of conditioned responding were skin conductance response (SCR) and retrospective US-expectancy ratings. For half of the participants (Generalization Group, GG), the subsequent extinction phase consisted of four nonreinforced presentations of generalization stimuli (GS+ and GS-). Participants from the Extinction control Group received an equal amount of nonreinforced presentations of the CSs. Finally, all participants were tested with the original CSs. The results from both measures clearly show an increase in the size of the discrimination upon the stimulus change after extinction in the GG. Because this pattern is not observed in the Extinction control Group, extinction performance appears to be somehow restricted to the perceptual characteristics of the extinction stimulus. Interestingly, the size of the conditioned SCR discrimination in the GG is not influenced by the stimulus change after acquisition. This observation points to a differential impact of stimulus change after acquisition vs. extinction treatment. The findings are discussed from the theoretical perspective of renewal and the clinical perspective of Return of Fear.
在一项人类恐惧条件反射实验中，32名参与者接受了差别条件反射程序训练，以几何形状作为条件刺激物（CS+和CS-，各呈现4次），电击作为非条件刺激物（US）。条件反应的测量指标为皮肤电反应（SCR）和对非条件刺激物预期的回顾性评分。对于一半的参与者（泛化组，GG），随后的消退阶段包括对泛化刺激物（GS+和GS-）进行4次无强化呈现。消退对照组的参与者接受等量的对条件刺激物的无强化呈现。最后，所有参与者都接受了对原始条件刺激物的测试。两种测量方法的结果均清楚地表明，在GG组中，消退后刺激变化时辨别力的大小有所增加。由于在消退对照组中未观察到这种模式，因此消退表现似乎在某种程度上局限于消退刺激物的感知特征。有趣的是，GG组中条件性SCR辨别的大小不受习得后刺激变化的影响。这一观察结果表明习得后与消退处理后的刺激变化具有不同的影响。从更新的理论视角和恐惧复发的临床视角对这些发现进行了讨论。
