Learned fear can be generalized through both perceptual and conceptual information. This study investigated how perceptual and conceptual similarities influence this generalization process. Twenty-three healthy volunteers completed a fear-generalization test as brain activity was recorded in the form of event-related potentials (ERPs). Participants were exposed to a de novo fear acquisition paradigm with four categories of conditioned stimuli (CS): two conceptual cues (animals and furniture); and two perceptual cues (blue and purple shapes). Animals (C+) and purple shapes (P+) were paired with the unconditioned stimulus (US), whereas furniture (C−) and blue shapes (P−) never were. The generalized stimuli were thus blue animals (C+P+, determined danger), blue furniture (C−P+, perceptual danger), purple animals (C+P−, conceptual danger), and purple furniture (C−P−, determined safe). We found that perceptual cues elicited larger fear responses and shorter reaction times than did conceptual cues during fear acquisition. This suggests that a perceptually related pathway might evoke greater fear than a conceptually based route. During generalization, participants were more afraid of C+ exemplars than of C− exemplars. Furthermore, C+ trials elicited greater N400 amplitudes. Thus, participants appear able to use conceptually based cues to infer the value of the current stimuli. Additionally, compared with C+ exemplars, we found an enhanced late positive potential effect in response to C− exemplars, which seems to reflect a late inhibitory process and might index safety learning. These findings may offer new insights into the pathological mechanism of anxiety disorders.

习得性恐惧可以通过感知和概念信息进行概括。这项研究调查了感知和概念的相似性如何影响这种概括过程。23 名健康志愿者完成了恐惧泛化测试，因为大脑活动以事件相关电位 (ERP) 的形式记录。参与者暴露于从头具有四类条件刺激 (CS) 的恐惧习得范式：两个概念线索（动物和家具）；和两个感知线索（蓝色和紫色形状）。动物 (C+) 和紫色形状 (P+) 与无条件刺激 (US) 配对，而家具 (C-) 和蓝色形状 (P-) 从来没有。因此，广义刺激是蓝色动物（C+P+，确定的危险）、蓝色家具（CP-P+，知觉危险）、紫色动物（C+P-，概念危险）和紫色家具（CP-P-，确定安全）。我们发现感知线索比恐惧获取过程中的概念线索引起更大的恐惧反应和更短的反应时间。这表明感知相关的途径可能比基于概念的途径引起更大的恐惧。在概括过程中，参与者更害怕 C+ 样本而不是 C- 样本。此外，C+ 试验引起了更大的 N400 振幅。因此，参与者似乎能够使用基于概念的线索来推断当前刺激的价值。此外，与 C+ 样本相比，我们发现响应 C- 样本的晚期正潜在效应增强，这似乎反映了晚期抑制过程并可能指示安全学习。这些发现可能为焦虑症的病理机制提供新的见解。