功能成像中的负激活及其网络探索

发布时间：2018-01-26 20:41

本文关键词： 负激活功能成像数字加工复杂网络　出处：《大连理工大学》2008年硕士论文　论文类型：学位论文

【摘要】： 负激活是脑功能成像研究中一种非常普遍的现象,但由于其机理尚不明晰,之前的脑功能研究主要集中在与任务相关的激活区域上,直到近来对负激活区域的研究才逐渐成为热点。在负激活的研究中发现包括后扣带回等脑区在不同的任务情况下均出现了相似的负激活现象,而这些脑区所参与的功能又是人脑最基本的认知功能,因此功能成像时的负激活可以反应人脑的基本状态,对研究人脑的基本认知功能有着重要的意义。本文基于功能磁共振成像技术对负激活现象分别采用SPM和复杂网络的分析方法对负激活现象进行了系统的研究和讨论。本文共分三部分内容: 1.对脑科学基础进行了较为全面的介绍。介绍和分析了几种常见的脑功能成像技术的成像原理及优势,并对脑功能数据分析软件包SPM的基本原理与数据处理方法做了介绍。 2.详细介绍了大脑中的负激活概念和研究现状,并对数字加工的认知实验中的负激活现象进行分析,除了后扣带回、前扣带回、楔叶,楔叶和前额叶内侧等区域之外,还发现了脑岛区域的显著负激活。结合各脑区在静息状态下的认知功能,对于负激活现象的生理机制做了初步分析,发现了脑岛在听觉认知中起着重要的作用。 3.将复杂网络理论引入到负激活的现象分析之中,建立了符号方向判别任务的负激活网络。通过对度值和介数值的计算,不仅从局域的角度阐述了网络中某个体与其他个体之间的相互作用,而且还从整体的角度研究了个体在系统中的作用。统计网络中度值和介数值前十大点所在的脑区,初步推测后扣带回是符号方向判别任务中负激活的关键性区域。
[Abstract]:Negative activation is a very common phenomenon in brain functional imaging, but because of its unclear mechanism, previous brain function studies mainly focus on task-related activation areas. Until recently, the research on the negative activation area has gradually become a hot topic. In the negative activation research, it was found that the brain regions including posterior cingulate gyrus showed similar negative activation phenomena in different tasks. The function of these brain regions is the most basic cognitive function of human brain, so the negative activation of functional imaging can reflect the basic state of human brain, and it is of great significance to study the basic cognitive function of human brain. In this paper, the negative activation phenomenon based on functional magnetic resonance imaging (fMRI) is systematically studied and discussed by using SPM and complex network analysis methods, respectively. There are three parts in this paper: 1. The basis of brain science is introduced, and the imaging principles and advantages of several common brain functional imaging techniques are introduced and analyzed. The basic principle and data processing method of SPM are introduced. 2. The concept and research status of negative activation in the brain are introduced in detail, and the phenomenon of negative activation in the cognitive experiment of digital processing is analyzed, except for the posterior cingulate gyrus, anterior cingulate gyrus and cuneiform lobe. In addition to the medial prefrontal lobe and wedge lobe, significant negative activation of the insular area was also found. The physiological mechanism of the negative activation phenomenon was preliminarily analyzed in combination with the cognitive function of the brain regions in the resting state. It is found that the brain island plays an important role in auditory cognition. 3. The complex network theory is introduced into the analysis of the phenomenon of negative activation, and the negative activation network of the symbolic direction discriminating task is established. The calculation of the logarithmic value and the medium value is carried out. Not only from the local point of view, the interaction between one body and other individuals in the network is expounded. At the same time, the function of individual in the system is studied from the whole angle. It is preliminarily assumed that the posterior cingulate gyrus is the key area of negative activation in the symbolic direction discrimination task.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2008
【分类号】：R445.2;R33

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