The popular paradigm of Pavlovian conditioned fear has been used to study learning and memory processes that mediate anxiety disorder. Fear extinction studies have often paired the conditioned stimulus (CS) and the unconditioned stimulus (US) on a subset of acquisition trials (partial reinforcement) to prolong extinction. However, there have been few studies on the effect of partial reinforcement and continuous reinforcement on fear generalization. To better understand the influence of the CS–US pairing rate on fear generalization, the experimenters used CSs paired with US at 50% (CS50), 75% (CS75), and 100% (CS100) during fear conditioning. A total of 66 participants, who were assigned at random to the different reinforcement rates, underwent fear acquisition and generalization tests on expectancy ratings and skin conductance responses. The continuous reinforcement group (CS100) showed a flatter generalization gradient, while the partial reinforcement groups (CS50, CS75) showed increased generalization magnitudes. These results suggest that the partial reinforcement extinction effect is related to threat intensity, whereas continuous reinforcement produces threat-sensitivity fear generalization, which has been used to explain the overgeneralization of fear.

巴甫洛夫条件恐惧的流行范式已被用于研究介导焦虑症的学习和记忆过程。恐惧消退研究通常将条件刺激 (CS) 和无条件刺激 (US) 配对到习得试验的子集（部分强化）以延长消退时间。然而，关于部分强化和持续强化对恐惧泛化的影响的研究很少。为了更好地了解 CS-US 配对率对恐惧泛化的影响，实验者在恐惧条件反射期间使用 50% (CS50)、75% (CS75) 和 100% (CS100) 的 CS 与 US 配对。共有 66 名参与者被随机分配到不同的强化率，他们接受了恐惧获得和对预期评级和皮肤电导反应的泛化测试。连续强化组（CS100）表现出更平坦的泛化梯度，而部分强化组（CS50，CS75）表现出更高的泛化幅度。这些结果表明，部分强化消退效应与威胁强度有关，而持续强化产生威胁敏感性恐惧泛化，这已被用来解释恐惧的过度泛化。