The Event-related Potentials Study Of Emotional Conflict

In our daily lives, we will face a lot of information and we need to extract some information while suppressing those who interfere with us. The goal-oriented behavior control and the suppression of interference information process are called conflict control. The information we received included emotional and non-emotional. Previous studies have studied the "pure" cognitive conflict control from different angles. The emotional conflict control in recent years more and more are involved by the researchers.The emotional conflict originated in cognitive conflict, which followed basic research paradigm in the conflict control such as Stroop, Flanker, Simon. There are three kinds experimental design in the topic of emotion and conflict control:one is the direct emotional conflict, participants judging emotional valence information and controlling the process of emotional information; the second category is the emotional cognitive conflict that target stimuli with a stimulation of emotional information, but participants the none motional information and controlling the process of non-emotional information; the last category is emotional conflict under the emotional background or in some emotional state, participants responding to the nonemotional target stimuli and controlling the process of non-emotional information. The purpose of this study is to explore the emotional conflict and its event-related potential characteristics. So, we selected the first type of experimental design used in this study, namely, direct emotional conflict in a specific experimental paradigm this study, Etkin et al (2006) and Egner et al (2008) used the word-face Stroop paradigm.Previous studies used the fMRI technology to investigate the neural mechanisms of emotional conflict. A number of studies have come to some conclusions and found some of the key brain regions of the emotional conflict, the brain spatial characteristics of the emotional conflict. But the timing process characteristic of the emotional conflict in the brain was largely unknown. Only an ERP study, Zhu et al (2010) found that emotional conflict detection at an earlier stage, but did not explore conflict resolution, and conflict adaptation process. Therefore, the purpose of this study is that used the event-related potentials (ERP) to study the timing process characteristic of the emotional conflict in the brain. In this study, we studied the emotional conflict resolution, conflict adaptation effect of emotional conflict and the similarities and differences between emotional conflict and cognitive conflict in several different angles.In this study, there were two ERP experiments. The experiment one focuses on the emotional conflict resolution and conflict adaptation effect. We used the previous trial (consistent, inconsistent)×current trial (consistent, inconsistent) two-factor with-in subjects design. Twenty participants completed the emotional conflict task by the "pleasant" and "fear" face as materials. Behavior results showed that there are significant emotional conflict effect and conflict adaptation effect. ERP results found two ERP components N350-550and P700-800. N350-550reflected that participants resolved the emotional conflict, and that participants resolved better conflict that followed by the incongruent trials. Source analysis found that N350-550source in ACC, a brain region associated with conflict monitoring and resolution by large previous, which reflected consistent with the previous fMRI results. P700-800might reflect the post-response monitoring. The experiment two mainly discussed the similarities and differences between emotional conflict and cognitive conflict. This experiment consists of two tasks, namely the emotional decision task and gender decision task. In the emotional conflict task participants judged the facial expression of the face while ignoring the emotional words in the face and in the cognitive conflict task participants judged the facial gender of the face while ignoring the gender words in the face. Behavior results found that participants have a significant Stroop conflict effect in the both task and would have a larger conflict in the cognitive conflict task. ERP results found three ERP components, P1-N2component of the early, mid-N450and late SP. N1-P2S reflected that participants need more attentional resource in the task which could speed up the conflict resolution. N450showed the significant conflict effect and the interaction between emotional conflict and cognitive conflict, those different waves in the cognitive conflict task being larger than those in the emotional conflict task, which were in accordance with the behavior results. These two experiments reveal the timing process characteristic of the emotional conflict in the brain and the different with the cognitive conflict.