Ahmed Ola, Lovibond Peter F
School of Psychology, UNSW Sydney, Sydney, NSW, Australia.
Q J Exp Psychol (Hove). 2019 Feb;72(2):118-131. doi: 10.1177/1747021818766461. Epub 2018 Mar 30.
Two experiments explored the role of verbalisable rules in generalisation of human differential fear conditioning with electric shock as the aversive stimulus. Two circles of different sizes served as conditioned stimuli (CS+ and CS-), before testing with a range of circle sizes. In Experiment 1, shock expectancy ratings followed a peak-shifted unimodal gradient, with maximum ratings at a test value further along the dimension from CS+ in the opposite direction to CS-. However, differentiable gradients were observed when participants were divided on the basis of the rules they reported using during the task (linear and similarity). Experiment 2 was designed to counter the contradictory feedback arising from extinction testing by removing the shock electrodes during the test phase. A more linear overall gradient was observed, and sub-groups defined by self-reported rules showed distinct gradients that were congruent with their rules. These results indicate that rule-based processes are influential in generalisation of conditioned fear along simple stimulus dimensions, and may help explain generalisation phenomena that have traditionally been attributed to automatic, similarity-based processes.
两项实验探究了可用言语表达的规则在以电击作为厌恶刺激的人类差异恐惧条件反射泛化中的作用。两个不同大小的圆圈用作条件刺激（CS+ 和 CS-），之后用一系列不同大小的圆圈进行测试。在实验1中，电击预期评分呈现出峰值转移的单峰梯度，在从CS+ 沿与CS- 相反方向的维度上进一步的测试值处达到最高评分。然而，当根据参与者在任务中报告所使用的规则（线性和相似性）进行分组时，观察到了可区分的梯度。实验2旨在通过在测试阶段移除电击电极来应对消退测试产生的矛盾反馈。观察到了更线性的总体梯度，并且由自我报告的规则定义的亚组显示出与其规则一致的不同梯度。这些结果表明，基于规则的过程在沿简单刺激维度的条件恐惧泛化中具有影响力，并且可能有助于解释传统上归因于自动的、基于相似性的过程的泛化现象。
