Abstract: Compared with positive and neutral stimulus, negative stimulus can arouse faster and more obvious reactions, this phenomenon is called negativity bias. Many studies showed that negativity bias was also existed in memory. According to evolutionary psychology, negativity bias served as an adaptive function for human beings to avoid dangerous situations. If this was true, young children should be more sensitive to negative information. After all, young children are physically vulnerable and short of knowledge of safety about their living environment. Negativity bias would help young children to aware and monitor potential dangers around them quickly and would increase their opportunities of survival. However, so far, only a few studies on negativity bias were done from a perspective of development and the results were inconsistent due to different methods and different range of ages. Researches on negativity bias of young children were even rare. In the present study, we conducted three experiments to investigate whether the negativity bias existed in four and five years old children’ memory for social actions. In experiment 1, we examined whether there were an advantageous memory for threatening social actions comparing to non-threatening or neutral social actions. Brief stories were presented to children with pictures. After learning about individuals who committed helping, threatening or neutral social actions, participants were asked to choose one from the three given behaviors for the protagonist. The result showed that participants had better memories for threatening actions than they did for helping or neutral actions. In experiment 2, we examined whether negativity bias existed for non-threatening events. Participants were told brief stories with pictures about individuals who were in a sad, happy or neutral emotional state. Again, a memory advantage for negative events was found in young children. In experiment 3, we examined whether negativity bias existed in prospective memory. Previous studies only investigated negativity bias refer to retrospective memory. However, in daily life, prospective memory is very important for children because adults always remind them to get away from dangerous people and events. If young children showed negativity bias in prospective memory, warning from adults was effective. Materials were the same with experiment 1. The prospective memory task was an ongoing task. Participants showed again negativity bias on threatening social actions relatively to helping and neutral social actions. These findings consistently suggested that as young as four and five years old children showed heightened memory for negative social actions over positive or neutral social actions. This is good for young children to predict and avoid harmful situations. No age difference was found in negativity bias between four years old children and five years old children. And this result suggests that even young children could have negativity bias, future study should extend to children under age four. The present study is the first one to explore whether young children show an advantageous memory for non-threatening social information and also is the first one to explore whether young children show an advantageous memory for threatening social information in prospective memory. Future study should investigate whether negativity bias for non-threatening social information exists in prospective memory.

Key words: emotion, negativity bias, memory, young children

摘要： 消极偏向是指相对于积极或中性的刺激，消极刺激能够获得更多的注意和认知加工。本研究采用故事法通过三个实验考察4-5岁儿童对社会事件的记忆是否存在消极偏向。实验一发现幼儿对威胁行为的回忆成绩显著优于对中性行为和助人行为的回忆成绩。实验二发现幼儿对悲伤事件的回忆成绩显著优于对中性和愉快事件的回忆成绩。实验三发现幼儿对威胁行为的前瞻记忆成绩显著优于中性和助人行为的前瞻记忆成绩。研究说明无论事件是威胁性的还是非威胁性的，无论是回溯记忆还是前瞻记忆，4-5岁儿童的记忆都表现出消极偏向。

关键词: 情绪, 消极偏向, 记忆, 幼儿