中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
基于功能磁共振成像的静息状态脑活动及功能连接分析

文献类型:学位论文

作者田丽霞
学位类别工学博士
答辩日期2006-05-28
授予单位中国科学院研究生院
授予地点中国科学院自动化研究所
导师蒋田仔
关键词功能连接 负相关 注意缺陷/多动障碍 functional connectivity , negative correlation attention deficit / hyperactivity disorder (ADHD)
其他题名Functional MRI Based Resting-State Brain Activity and Functional Connectivity Analyses
学位专业模式识别与智能系统
中文摘要目前基于静息状态(resting-state)功能磁共振成像(functional MRI,fMRI)的研究已经越来越多。这些研究绝大多数考察基于血氧水平(blood-oxygen level dependent,BOLD)的fMRI信号中低频成分(也称慢波振荡)的同步性,也即从功能整合的角度研究脑区之间的功能连接。基于静息状态功能磁共振成像,本文除了在功能连接分析方面开展研究工作之外,还提出一种检测静息状态下脑活动的方法,并将其应用于精神疾病研究。本文的具体研究内容和取得的创新之处如下: 1. 本文提出一种整合fMRI信号时间域和空间域信息的“静息状态脑活动指标”,用以检测静息状态下的脑活动。我们采用该指标度量注意缺陷/多动障碍(Attention Deficit / Hyperactivity Disorder,ADHD)青少年与正常对照静息状态下的脑活动差异,发现与正常对照相比,ADHD患者在感觉皮层和感觉相关皮层表现更为显著的静息状态脑活动。我们认为ADHD患者表现的这些更为显著的脑活动与他们的注意缺陷症状是一致的。 2. 本文首次在静息状态下从功能整合的角度研究了ADHD青少年的背侧前扣带回功能网络异常模式,我们发现与正常对照相比,ADHD青少年背侧前扣带回与双侧脑干、双侧脑岛、双侧丘脑、双侧小脑等脑区的功能连接显著增强。我们认为这一结果可能反映了ADHD患者的自主控制异常。 3. 本文首次研究了静息状态下BOLD信号之间负相关的稳定性,我们发现静息状态下人脑的视觉、运动皮层与其它脑区的BOLD信号之间表现不稳定的负相关。这一发现的意义在于:它提示我们在作基于静息状态功能磁共振成像的功能连接分析时,对于涉及负相关的结果需要谨慎解释以避开负相关不稳定性的影响。
英文摘要More and more resting-state functional MRI (fMRI) studies have been carried out in recent years. Most of these studies investigated the synchrony of low frequency fluctuations (LFFs) of blood-oxygen level dependent (BOLD) signals, that is, they analyzed the functional connectivities between brain regions from a functional integration perspective. Based on resting-state fMRI, we carried out studies not only on the applications of functional connectivity analyses, but proposed a novel method to detect resting-state brain activities, and applied the method to psychiatric disease analyses. The contents as well as the innovations of these studies are as follows: 1. We proposed a resting-state activity index (RSAI), which utilizes both the spatial and temporal information of BOLD signals, to test the resting-state brain activities. We evaluated the resting-state brain activities of the attention deficit / hyperactivity disorder (ADHD) patients and their matched controls by using RSAI, and compared the brain activity pattern differences between the two groups. We found that the ADHD patients exhibited more significant resting-state activities in sensory and sensory related cortices. We suggest that these more significant resting-state activities in the ADHD patients may be related to the inattention symptoms in them. 2. For the first time, we analyzed the dorsal anterior cingulate (dACC) functional connectivity pattern differences between the ADHD adolescents and their matched controls by using resting-state fMRI. We found that the bilateral brainstem, pons, bilateral insula, bilateral thalamus, bilateral cerebellum and bilateral posterior cingulate cortex exhibited more significant functional connectivities with the dACC in the ADHD adolescents. We suggest that the more significant dACC functional connectivities in the ADHD patients might be result from the autonomic control abnormalities in these patients. 3. For the first time, we analyzed the stabilities of the negative correlations of resting-state BOLD signals. We found that the negative correlations associated with the motor and visual cortices were unstable. The significance of this study lies in that it highlighted the importance of paying attention to the influence of the stabilities of negative correlations of BOLD signals in related studies and establishes the need for further studies on negative correlations of BOLD signals.
语种中文
其他标识符200318014603026
源URL[http://ir.ia.ac.cn/handle/173211/5916]  
专题毕业生_博士学位论文
推荐引用方式
GB/T 7714
田丽霞. 基于功能磁共振成像的静息状态脑活动及功能连接分析[D]. 中国科学院自动化研究所. 中国科学院研究生院. 2006.

入库方式: OAI收割

来源:自动化研究所

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