Abstract: There were all sorts of different events which may arouse our emotional experiences in daily life. When processing and perceiving these emotional stimuli, there may include different emotional reactivity. They could be influenced by biological factors as well as cultural factors. It had been recognized that emotions exist along a social/nonsocial emotional dimension. The sociality dimension may reflect the differences between basic biological drives (nonsocial) and complex social interaction (social). Even though previous studies examined the important differences in social and non-social emotional stimuli, most of them focused on the negative emotions. However, as an important and indispensable part of the field of emotion study, it is necessary to include the study of positive emotions. Positive emotions are considered to be adaptive experiences and helpful to promote individual's psychological well-being. In current study, we aimed to examine the differences of the emotional reactivity when processing social/nonsocial positive emotions. Emotion perception is a process that integrates physiological, cognitive, and behavioral components. A series of even-related brain potential (ERP) studies is reviewed demonstrating the consistent and robust modulation of specific ERP components by emotional images. Specifically, emotional compared to neural pictures elicit an increase in the early ERP components (e.g., P1, P2, and N2) and the late positive potential (LPP). Modulations of the ERP components are thought to reflect the facilitated processing of, and increased attention to, motivationally salient stimuli. Therefore, ERPs provide a powerful measurement tool for capturing neural activity related to emotional responding. In the present ERP study, we used the Picture Perception Paradigm to explore the differences in brain cortical reactivity to social/nonsocial positive emotions. When 20 undergraduates watched and evaluated these social, neutral, and nonsocial pictures, their ERPs were recorded. 180 pictures were used in the study. Results showed that (1) the P1was larger for emotional than neutral pictures. As for P2, the difference was not significant, (2) the N2 was larger for social than nonsocial pictures; but had no significant differences between emotional and neutral pictures, (3) as for LPP, we divided into three time windows: the first one was from 300ms to 600ms, the second one was from 600ms to 1000ms, and the last one was from 1000ms to 1500ms. At the early time window, there were no significant results among different stimuli. At the second and the third time windows, the LPP was larger for social than nonsocial pictures. However, there was no significant difference between emotional and neutral pictures. The results suggested that positive social emotions properly had a higher priority during the emotional processing. And the advantage could be reflected in subjective experiences and physiological responses. These findings deepened our understandings of social/nonsocial emotions. Besides, these results could also provide empirical supports to processing of positive emotions. The future research could make significant progress in laying out the foundations identifying the diverse mechanism of emotional processing of different emotional stimuli.

Key words: Social Emotions, Positive Emotions, Even-related Potential (ERP), Emotion Processing

摘要： 个体情绪加工具有其生物基础，也受到文化因素的影响。社会性和非社会性情绪刺激加工可能存在不同的机制。然而，以往大多数研究主要关注负性情绪的加工差异。因此，本研究选取大学生被试20名采用图片感知范式（Picture Perception Paradigm）探讨个体在加工社会性和非社会性正性情绪刺激的脑电位活动差异。研究发现：（1）在P1成分上，情绪图片诱发的波幅要显著大于中性图片。（2）在N2成分上，正性社会情绪图片诱发的波幅要显著大于正性非社会情绪图片（3）在早期时间窗中，由正性社会情绪图片与非社会情绪图片诱发的LPP波幅差异不显著。在中期时间窗中，正性社会情绪图片与非社会情绪图片的LPP波幅差异显著。晚期时间窗中，正性社会情绪图片诱发的LPP波幅显著大于正性非社会情绪图片。由此，相对于非社会性请刺激来说，正性社会情绪刺激在加工上可能占据优势地位。

关键词: 社会性情绪, 正性情绪事件, 相关电位, 情绪加工