感知情绪与自我体验情绪加工的神经机制：基于fMRI的多变量模式分析

Multi-Variate Pattern Analysis(MVPA) method was applied to study the neural mechanism of emotional processing based on functional MRI, and to study the representation of emotion in the brain using the idea of functional connectivity network.The perceived emotion and self-experienced emotion were concerned.Emotional facial expression pictures were used to acquire the fMRI data of perceived emotion. Using the same pictures as cue, subjects were instructed to recall the emotional self-experienced events in the past 12 months. Three questions were concerned: 1)the neural mechanism supports of discret category theroy and the underlying dimentional theory: the discriminability of the brain states induced by different types of basic emotions,and the discriminability of the emotions with different valence and arousal levels. 2)the difference between perceived emotion and self-experienced emotion: the spatial similarity will be calculated based on MVPA method to explore the neural mechanism difference of these two types of emotion. 3) The idea of functional connectivity network will be applied to study the neural mechanism of emotion. In summary,the neural mechanisms of two basic types of emotion, the perceived and self-experienced emotion were explored using MVPA method, especially the functional connetivity network idea was applied to explore the nature of emotion. The results will enhance the understanding of emotion and provide scientific support for the diagnosis and treatment of emotional disorder related mental illness.

本项目基于功能磁共振成像技术，以感知情绪、自我体验情绪为研究对象，利用多变量模式分析方法，以功能网络的思想对情绪加工的脑机制进行研究。研究以面部表情图片作为刺激材料，获得被试对感知情绪的数据；以相同的面部表情图片作为提示，诱发被试通过自传体回忆的方法产生对特定情绪的体验。具体研究以下内容：1）情绪的范畴理论与维度理论的神经基础：不同类别的基本情绪所诱发的脑部激活模式的可分性研究；不同唤醒与效价水平上的情绪的可分性研究。 2）感知情绪与自我体验情绪的神经机制的差异：利用多变量模式分析方法对情绪知觉与情绪自我体验数据开展空间相似度分析，探索二者在神经机制上的异同。3）构建情绪加工的脑网络模型。本项目将通过开展两种类型的情绪的脑机制研究促进对情绪的理解，特别是以功能网络的思想来探究情绪的本质，同时也为情绪障碍的众多精神疾病的诊断与治疗提供科学依据。

本项目基于功能磁共振成像技术、事件相关电位技术及神经影像计算方法对对感知情绪及自我体验情绪加工的神经机制进行了研究。主要研究结果包括：1）基于快速事件相关设计的fMRI研究，利用单变量广义线性模型的分析结果发现，快乐与中性情绪面孔、愤怒与厌恶面孔分别表现出相似的脑区激活模式，MVPA算法的解码结果发现这两种组合分类正确率最低，该结果为情绪的维度编码理论提供了证据。2）对厌恶、恐惧、中性面孔与场景刺激加工的时间进程差异分析发现，无论中期还是晚期的加工过程中，面孔刺激的感知性都比场景刺激强，表现为更大的事件相关电位成分，早期后部负电位EPN与晚期正成分LPP。一种特殊情况是，个体在晚期阶段对恐惧场景更敏感。结果表明，面孔与场景的加工受到刺激类型的调制，具有不同的注意资源分配方案。3）对大型情绪影片数据库FilmStim的本土化评定结果发现，中性影片可作为其他情绪的控制条件；除愤怒外的负性影片可有效诱发目标情绪；正性情绪影片没有有效诱发目标情绪，存在较大文化差异。本研究的结果可以为国内研究者使用 FilmStim 刺激库中的影片进行研究时提供一定依据。