Preparedness theory is one of the most influential ideas in explaining the origin of specific phobias. The theory proposes that fear conditioning is selective to animals that have posed a threat to survival throughout human evolution, and that acquired fear memories to such threats are resistant to extinction. We reviewed fear conditioning studies testing whether autonomic responses conditioned to pictures of snakes and spiders show greater resistance to extinction than neutral cues. We identified 32 fear conditioning experiments published in 23 studies including 1887 participants. Increased resistance to extinction of conditioned responses to snake and spider pictures was found in 10 (31%) of the experiments, whereas 22 (69%) experiments did not support the hypothesis. Thus, the body of evidence suggests that preparedness theory does not explain the origin of specific phobias.

防范理论是解释特定恐惧症起源的最有影响力的思想之一。该理论提出，恐惧条件对那些在整个人类进化过程中对生存构成威胁的动物具有选择性，并且对这些威胁的后天恐惧记忆能抵抗灭绝。我们回顾了恐惧条件研究，测试了适应蛇和蜘蛛照片的植物自主反应是否比中性提示表现出更大的灭绝抵抗力。我们确定了23项恐惧调节实验，这些实验发表于23项研究中，包括1887名参与者。在10（31％）个实验中发现对蛇和蜘蛛图片的条件响应灭绝的抵抗力增强，而22个（69％）实验不支持该假设。因此，