Studies On The Effect Of Positive And Negative Emotion Priming On Impulse Control

Controversial results remaining unresolved in today's researches about emotion effect: First, the theory of negative bias indicates that the human brain is especially sensitive to emotionally negative events, and these events are preferentially processed relative to neutral and positive events. However, considerable behavioral studies have shown that negative stimuli caused slower reaction time and higher error rate. Why the preferentially proceeding in the brain doesn't bring the faster reaction time in behavior? Second, Fredrickson's"Broaden and build"theory believes that negative emotions narrowed individuals'momentary thought-action repertories by calling forth specific action tendencies, however positive emotions broaden individuals'momentary thought-action repertoires, prompting them to pursue a wider range of thoughts and actions than is typical. Also, the theory doesn't agree with the behavioral results we mentioned above.What makes this happened? Maybe the reason lies in the characteristic of different emotions. In our studies, we are trying to create different conditions for emotion, and trying to find the mechanism and feature of the impact of different emotion, to find a reasonable interpretation about these results.The mental process we selected in our study is impulse control. There are three kinds of impulse control process in our study: The first one is immediate impulse control, participants need to react as soon as possible when the stimulus showed in the screen. Second, delayed impulse control, participants have to react as soon as possible when the stimuli disappeared from the screen. The third, chosen impulse control, participants have to react as soon as possible according to the coming second stimulus. The relations between these three tasks are related and step up. The show time of the pictures was longer and longer from study 1 to study 3. So there are three sub-studies in our study, and each sub-study involved two tasks, the first one is to explore the feature of the impulse control task, and the second is to investigate the impact of different emotion to the process of impulse control.The first study is immediate impulse control. The paradigm we used in our study was the traditional Go-Nogo task, participants need to react as soon as possible to the target stimuli and not react to the other. The results showed that negative stimuli elicited higher mean amplitude than positive and neutral stimuli. In behavioral data, negative stimuli showed longer reaction time and higher error rate than positive and neutral conditions. The ERP results were agreed with negative bias theory about emotion, but the behavioral data confirmed the results of present behavioral studies. According to the results from study 1, the controversial we mentioned above remained unresolved. So we need deeper studies about the effect and mechanism of different emotions. The task we used in study 2 was revised from the character of the paradigm in study 1. The differences between these two tasks were the time to react. In task 1, participants need to react as soon as possible when the target stimuli appeared in the screen, but in task 2, participants were asked to react when the target stimuli disappeared. In order to elicit the impulse to react, we randomized the showing time of the picture and we will reward the fastest five people with a book (we let them know the reward before experiment). To our surprise, negative stimuli in study 2 didn't showed higher mean amplitude as in study 1 in ERP results. In behavioral data, no longer reaction time was found in negative stimuli than positive and neutral ones. But on the other side, positive stimuli elicited higher mean amplitude, longer reaction time and high error rate. It means that positive stimuli made the task harder to finish. In total, the ERP results can be explained by Fredrickson's"broaden and build"theory, and the behavioral results now showed different characters from study 1.Study 3 was intended to investigate the emotional effect when participants had a longer time than study 2 to see and experience the emotion of the pictures. The results indicated that negative stimulus showed shortest reaction time and lowest error rate than positive and neutral emotions. But the positive emotion showed slower reaction time and higher error rate, the results deepened the results of study 2.From the comparison of the emotion effect among study 1, 2, and 3, we can indicate the ways of the effect of positive emotion and negative emotion to impulse control. For negative emotions, the effects are changing from disturbing to no effect then change to promoting, when the showing time of the pictures becoming longer. On the contrary, positive emotions showed a different way when the showing time of the picture was prolonged.The main reason here lies in the evoking effect of emotion pictures in different tasks. In study 1, participants have to react to the picture and press relevant keys as soon as possible, emotion was not effective elicited in this task, and the result was coming from the character of the pictures but not the emotion contents of the picture. But in study 2 and 3, when participants had a longer time to see the pictures, the emotion was elicited effectively in these tasks, so the emotion showed a different effect in ERP results and behavioral data. From what we discussed above, we can find that these results can explain the controversies we mentioned above properly.