【作者】 董光恒；

【导师】 杨丽珠；

【作者基本信息】 辽宁师范大学 ， 发展与教育心理学， 2008， 博士

【摘要】 当前对积极情绪与消极情绪作用的研究存在两个相互矛盾的结论:首先,情绪的负性偏向观点认为消极情绪刺激拥有一种认知加工上的优先权。而大量行为研究的结论却表明在积极情绪启动下被试反应速度快,在消极情绪启动下被试反应速度慢。问题在于,为什么负性情绪在认知加工上的优先权并没有带来更快的行为反应速度?其次,“拓展-塑造理论”认为,处于消极情绪状态时,个体思维往往聚焦于引起消极情绪的事件或情境,心态变得警惕而紧张,而处于积极情绪状态的个体思维开阔、心态积极而放松。问题是,引起心态警惕的消极情绪未能产生更快的反应速度,而引起心态放松的积极情绪却反应更迅速?分析造成这一结果的原因,应该从不同研究之间的差异入手。首先,不同研究之间在研究手段上存在差异:情绪负性偏向的研究主要属于认知神经科学范畴;行为研究是传统的研究途径,主要应用反应时和准确率指标;“拓展-塑造理论”更多是从进化角度对情绪进行论述。其次,不同任务所侧重的认知加工不同:情绪负性偏向研究主要测查的是人类对刺激图片的自动加工过程;行为研究更多侧重认知与行为判断过程;“拓展-塑造”理论则倾向对应激和心境状态下个体反应进行描述。综上,我们认为问题的核心在于情绪在不同的认知加工过程作用方式存在差异。本研究选择的心理过程为冲动控制过程,共有三种冲动控制任务,每个任务所侧重的认知加工过程存在差异:即时冲动控制,侧重在迅速反应任务情境中被试控制冲动时的特征;延时冲动控制,侧重在短暂持续的情境中被试冲动控制的特征;选择冲动控制,侧重被试依据即将出现的刺激进行选择反应的过程。不同任务之间呈现出递进的关系,所侧重的认知加工过程不同,并且观看刺激图片的时间也逐渐延长。在验证不同冲动控制实验范式的基础上,我们对被试施加情绪刺激,测查在积极情绪和消极情绪启动下被试冲动控制过程表现出的特征差异。情绪刺激对即时冲动控制影响的行为结果发现,消极情绪刺激对被试冲动控制过程带来干扰,积极情绪刺激无显著影响。脑电研究结果验证了情绪负性偏向的观点。同时对大脑前额叶区域左右侧电荷对比未发现偏侧化效应,表明情绪未能得到理想的诱发。因此,在这一过程中不存在情绪与认知相互作用的条件。那么是什么原因造成了积极情绪与消极情绪之间作用的差异?情绪刺激图片中图片属性是唯一的变量。因此,恰当的解释是:在迅速判断任务中图片辨别和认知判断之间存在着对有限注意资源的竞争,由于消极情绪图片具有的某些特性,它能够快速地吸引更多注意资源的投入,所以干扰了认知判断过程。情绪刺激对延时冲动控制影响的行为结果表明,消极情绪刺激在不需要大量注意资源的早期加工任务中未起到干扰作用,而积极情绪启动使任务难度增加。脑电结果同样验证了情绪负性偏向的观点。对大脑左右侧电荷对比发现明显的情绪偏侧化效应,表明情绪得到了较好的诱发。因此,用情绪与认知之间交互作用观点来解释本研究结果比较合理。同时,这一研究结果符合“拓展-塑造理论”对积极情绪与消极情绪特点的论述。情绪刺激对选择冲动控制影响的行为结果发现,消极情绪刺激未表现出干扰作用,甚至在一定程度上表现出促进作用,而积极情绪仍然表现出干扰作用。脑电结果验证了情绪负性偏向的观点。总体上,这一结果是对研究2结果的验证和拓展,特别是在消极情绪的作用上。综合以上3个研究不同情绪作用特征的变化,我们发现,随着被试感受情绪图片时间的延长,积极情绪的作用表现为从无作用到产生干扰作用,而消极情绪的作用表现为从产生干扰作用到无影响再到产生促进作用。从另一个角度来说,随着认知过程的延长,情绪诱发效果的增强,积极情绪表现出干扰作用,而消极情绪随着认知过程的延长得到更充分诱发,从最初表现出干扰作用到后来产生促进作用。产生这一转变的原因应该从不同刺激所具有的自身特征以及在不同加工任务过程中情绪是否得到有效而充分的诱发两个方面寻找解释。综合分析不同冲动控制任务的特征可以发现,我们修改后的研究任务都与原任务具有较高的一致性,都重点测查冲动控制过程。特别是研究发现传统冲动控制敏感成分N2受按键准备状态的影响,并且产生了新的可能与认知冲动控制相关的成分P270。综合分析积极情绪与消极情绪刺激对冲动控制影响的研究结果可以发现,情绪的作用在不同的认知加工阶段具有不同的作用机制:在识别判断阶段,情绪的作用更多表现在对有限注意资源的竞争上;在认知维持和加工阶段,情绪的作用来源于情绪与认知之间的交互作用。其中,情绪是否得到充分诱发是导致不同研究结果的决定性因素。这一研究结论合理地解释了当前在对积极情绪与消极情绪作用研究中存在的一些相互矛盾的结论。同时,这一研究结果也表明,情绪负性偏向的产生应该来自于刺激图片的特征,而不是刺激图片所诱发的情绪特性。这是很有挑战性的结论,未来研究将从多个侧面对这一结论进行验证。更多还原

【Abstract】 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.更多还原