情绪调制感觉通道信息加工和注意资源的神经机制

发布时间：2018-06-02 15:43

本文选题：情绪面孔 + 视觉搜索　；参考：《西南大学》2014年硕士论文

【摘要】：注意资源和感觉通道信息加工能力有限性使得人们往往只能关注于周围环境中最重要的部分,这也促使人们通过选择性注意来优先加工与个人相关或具有显著性意义的信息。然而哪些信息是与个人生存、发展相关的显著性信息呢?以往的研究表明,情绪性刺激在注意选择过程中扮演着非常重要的角色,对比中性刺激,个体更加倾向于注意那些带有情绪色彩的信息,这种注意的启动甚至是以一种自动化、无意识的方式运作的。在情绪性刺激之中,又可以根据效价区分为正性、负性刺激。由于负性刺激,特别是威胁性刺激对于个体的生存与发展具有至关重要的作用,个体进行不同效价的情绪刺激加工时,往往会优先加工负性刺激的信息,使得负性刺激在强化感知觉能力方面更具优势,这一现象也被称为“负性偏向”效应。这种效应在很多行为范式中进行了研究,例如在视觉搜索范式中,当目标刺激带有情绪色彩或威胁性信息,对比中性目标及友善性刺激,它们被探测的速度更快也更准确。其他的注意范式中的研究,如注意瞬脱、Stroop范式、点探测范式等也表明情绪刺激尤其是负性情绪能够获得更多的加工资源。随着认知神经成像技术的发展,越来越多的研究采用功能性磁共振(fMRI)和事件相关电位(ERP)技术来探讨情绪对感知觉影响的神经机制。fMRI技术提供了高精度的空间分辨率,研究表明情绪会调制杏仁核和感觉加工通道间的反馈通路,并且通过调节额顶注意网络的参与来加工情绪性刺激。对比fMRI而言,ERP技术则提供了观测大脑在短时程内进行不同认知加工过程的窗口。研究表明在情绪加工过程中,早期的感知觉加工成分,中期、晚期的涉及注意、认知资源的成分都会受到情绪的调制。但以往的ERP研究也存在一些尚待解决的问题,例如早期的面孔加工成分N170是否受到情绪的调制没有统一的定论,晚期认知成分P300在情绪中的作用因采取的范式带来的干扰效应受到质疑,而且大部分研究也缺乏对应的行为证据的支撑。因此,在当前研究中采用了高时间精确度的ERP技术,结合可以避免以往范式带来的一些干扰效应的情绪面孔视觉搜索范式来证实情绪加工所涉及到对感觉通道、注意资源调控影响的神经机制及其具体认知加工流程,并提供行为数据的支持。当前研究采用ERP技术结合情绪面孔的视觉搜索范式。视觉搜索范式需要在同时呈现的多个刺激中寻找具有某一特征的目标刺激,其余的则称为分心物。研究中所采用的目标刺激为情绪性面孔(威胁性面孔或友善性面孔),分心物则为中性面孔,被试的任务为在同时呈现的多个面孔中判断是否存在不一致的面孔表情,即是否存在情绪性面孔。所有试次中,存在不一致面孔表情和均为一致面孔表情各占一半,而存在不一致面孔表情的试次中,目标情绪为威胁性面孔和友善性面孔的试次各占一半。实验的目的在于比较存在不一致面孔表情的试次中两种不同效价的目标情绪面孔出现时,被试进行反应的行为表现以及所记录的脑电差异。根据前面所论述的研究思路,所涉及到的ERP成分,主要关注于早期的面孔特定加工成分N170,中期的表征视觉空间注意资源投入的N2pc,以及晚期的涉及到认知资源调控的P300成分。经过数据采集及分析后,发现结果如下： (1)行为表现上,在含有威胁性面孔的视觉搜索中,对比含有友善性面孔被试的反应速度更快,并且更准确,体现了威胁性面孔优先加工的效应,表明威胁性面孔可以更好的强化被试的感知觉能力；(2)早期的ERP成分N170,作为面孔加工的特定成分,受到了情绪效价的调制,表现为威胁性面孔对比友善性面孔诱发了更大的波幅。除此,也存在与以往研究结果一致的右半球主导优势,即在右边电极点产生了更大的N170波幅；(3)中期表征视觉空间注意资源投入的N2pc,受到了情绪效价的调制,表现为威胁性面孔对比友善性面孔诱发了更大的波幅,表明威胁性面孔开始吸引了更多的空间注意资源投入；(4)晚期表征认知资源调控的P300也受到了情绪效价的调制,表现为威胁性面孔对比友善性面孔,其波幅更大,表明晚期的认知资源也在持续的进行投入,从而确保了对威胁性面孔的优先加工。另外,我们发现当目标出现于左侧时,对比右侧P300的波幅更大。由于以往研究认为P300成分源活动与额顶叶具有一定的对应关系,表明晚期可能涉及到额顶控制网络对情绪的进一步加工；(5)在将行为表现与ERP波幅进行关联时,并没有发现早期和中期的波幅与行为表现相关,只发现P300的波幅大小与行为反应的快慢具有一定的对应的关系,这在某种程度上也符合了前人所认为的P300与行为反应决策的相关。情绪加工中所体现出的威胁性面孔优先加工效应及情绪对被试感知觉能力的影响可以从ERP不同时期的成分寻找到其存在的认知加工流程的神经机制。这种认知加工过程涉及到情绪对早期的感觉加工成分的调制,以及中晚期注意资源的持续输入,正是通过多种神经机制在不同时间流程上参与共同导致了情绪对被试感知觉能力的调节。结果中表明的N170,P300所体现的情绪效价效应,则进一步解决了前人关于这两种波幅是否受到情绪调制的问题,行为数据的支撑也使得研究的结果更具有说服力。这为情绪加工的神经机制流程所涉及的对感觉通道和注意资源的调控提供了直接而系统的证据。
[Abstract]:Attention to the limited processing capacity of resources and sensory channels makes people tend to focus only on the most important parts of the surrounding environment, which also encourages people to prioritize personal or significant information through selective attention. But what information is the significant information related to life and development? The previous studies have shown that emotional stimuli play a very important role in the process of attention selection. Compared to neutral stimuli, individuals are more inclined to pay attention to those emotional information. The start of this attention is even operated in an automated, unconscious manner. In emotional stimuli, it can be differentiated according to titer. It is a positive, negative stimulus. The negative stimulus, especially the threat stimulus, plays a vital role in the survival and development of the individual. When individual emotional stimuli are processed at different titers, the information of negative stimuli is often preceded, making negative stimuli more advantageous in the enhancement of perceptual ability. This phenomenon is also known as the phenomenon. It is a "negative bias" effect. This effect is studied in many behavior paradigms, such as in the visual search paradigm, when the target is stimulated with emotional or threatening information, compared to neutral targets and friendly stimuli, they are detected faster and more accurately. His attention paradigm, such as attention blink, Stroop Paradigms, point detection paradigms and so on also show that emotional stimuli, especially negative emotions, can acquire more processing resources.
With the development of cognitive neuroimaging technology, more and more studies have adopted functional magnetic resonance (fMRI) and event related potential (ERP) technology to explore the neural mechanism of the emotion effect on sensory perception, which provides high precision spatial resolution. The study shows that emotion will adjust the feedback pathways between the amygdala and sensory processing channels. In contrast to fMRI, ERP technology provides a window to observe the different cognitive processes of the brain during the short term. However, there are still some problems to be solved in the previous ERP research, such as whether the early face processing component N170 is not determined by the modulation of emotion, and the effect of the late cognitive component P300 in the mood is questioned by the paradigm of the paradigm, and most of the studies lack correspondence. Therefore, the high time precision ERP technology is used in the current research, and the emotional face visual search paradigm, which can avoid some interference effects from the previous paradigm, is used to confirm the neural mechanism and the specific cognitive processing flow of emotional processing. Provide support for behavioral data.
The current study uses the ERP technology to combine the visual search paradigm with emotional faces. The visual search paradigm needs to find a target stimulus with a certain feature in the multiple stimuli presented at the same time. The rest is called a distractor. The purpose of the study is to stimulate an emotional face (a threatening face or a friendly face), and the distractor is in the middle. The task is to determine whether there is an inconsistent face in the multiple faces that are presented at the same time, that is, whether there is an emotional face. The purpose of the experiment is to compare the performance of the two different target emotional faces with different facial expressions, and the behavioral performance of the response and the recorded EEG differences. According to the previous research ideas, the ERP components involved are mainly focused on the early stage. The specific processing component of the face, N170, N2pc in the medium of visual space attention resources, and the late P300 components involved in the regulation of cognitive resources. After data collection and analysis, the results are as follows:
(1) in the behavioral performance, in the visual search with a threatening face, the response rate of the subjects with friendly faces is faster and more accurate, reflecting the effect of the threat face priority processing, indicating that the threat face can better strengthen the perception ability of the subjects; (2) the early ERP component, as the special face processing. The definite component, which is modulated by the emotional valence, shows that the threat face contrasts the friendly face with the greater amplitude. In addition, there is a dominant dominance of the right hemisphere, which is consistent with the previous research results, that is, a larger N170 amplitude is produced at the right electrode point; (3) the N2pc in the visual space attention resource input in the metaphase surface is affected by the emotion. The potency modulation, which shows that the threat face contrasts the friendly face with the greater amplitude, indicates that the threatening face begins to attract more space attention resources; (4) the P300 of the late representation cognitive resource regulation is also modulated by the emotional validity, showing the greater amplitude of the threat face compared to the friendly face. The cognitive resources in the late Ming Dynasty are also continuing to invest, thus ensuring the priority of a threatening face. In addition, we found that when the target appears to the left, the amplitude of the contrast to the right P300 is greater. Since previous studies suggest that the activity of the P300 component has a certain corresponding relationship with the frontal parietal lobe, indicating that the late stage may involve the frontal control. Further processing of the mood of the network; (5) when the behavior performance is associated with the ERP amplitude, there is no correlation between the amplitude and the behavior in the early and middle stages. It is found that the amplitude of the P300 has a certain corresponding relationship with the speed of the behavior response, which in some degree also conforms to the P300 and the behavior of the predecessors. The decision should be related.
The effects of the threat face priority processing and the emotion on the perception ability of the subjects in the emotional processing can be found from the components of different periods of ERP to the cognitive processing process of the cognitive processing process. This cognitive process involves the modulation of emotional additive components in the early stage, and the attention resources in the middle and late stages. The continuous input, through a variety of neural mechanisms involved in different time processes, leads to the adjustment of emotion to the perceptual ability of the subjects. The result of the emotional titer effect shown by N170 and P300 further solves the problem of whether the two kinds of wave amplitude is modulated by emotion, and the support of behavioral data is also made. The results of the study are more convincing. This provides direct and systematic evidence for the regulation of sensory pathways and attention resources involved in the process of emotional processing.
【学位授予单位】：西南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：B842

【共引文献】