Functional connectivity of the fusiform gyrus during a face-matching task in subjects with mild cognitive impairment
Functional connectivity of the fusiform gyrus during a face-matching task in subjects with mild cognitive impairment
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DOI：
10.1093/brain/awl051
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发表时间：
2006-05-01
期刊：
影响因子：
14.5
通讯作者：
Hampel, H
中科院分区：
文献类型：
--
作者：
Bokde, ALW;Lopez-Bayo, P;Hampel, H
认知功能需要支持认知的网络区域之间高度的功能相互作用。假设大脑激活变化表明疾病进展到晚期，那么功能连接性的变化可能先于大脑激活的变化。本研究的目的是在面部匹配任务执行过程中，研究轻度认知障碍（MCI）患者右侧梭状回中部（FG）功能连接性的变化。右侧梭状回中部是处理面部刺激的关键区域。使用功能性磁共振成像测量大脑活动。有16名MCI患者和19名年龄匹配的健康对照者。线性相关系数被用作右侧梭状回中部与大脑中所有其他体素之间功能连接性的度量。在任务表现或组间激活方面未发现统计学差异。健康对照组和MCI组的右侧梭状回中部与视觉皮层、顶下小叶和顶上小叶、背外侧前额叶皮层（DLPFC）以及前扣带回呈强双侧正线性相关。健康对照组右侧梭状回中部与视觉皮层、顶叶和右侧DLPFC的正线性相关性高于MCI组，而MCI组在左侧楔叶的正线性相关性更高。在健康对照组中，右侧梭状回中部与右侧内侧额叶回和颞上回以及左侧顶下小叶（IPL）、角回、额上回和前扣带回呈负线性相关，但MCI组与左侧IPL、角回、楔前叶、前扣带回以及右侧颞中回和后扣带回呈负线性相关。在负线性相关区域，MCI组与额叶区域、右侧颞上回和左侧IPL的功能连接性降低。楔叶和IPL的不同区域在两组中功能连接性均增强。MCI中可能存在的阿尔茨海默病神经病理学影响从右侧梭状回中部到视觉区域和内侧额叶区域的功能连接性。此外，MCI组在顶叶的较高线性相关性可能表明代偿过程的初步出现。结果表明，功能连接性可以作为检测MCI患者大脑功能变化的有效标志物。
Cognitive function requires a high level of functional interaction between regions of a network supporting cognition. Assuming that brain activation changes denote an advanced state of disease progression, changes in functional connectivity may precede changes in brain activation. The objective of this study was to investigate changes in functional connectivity of the right middle fusiform gyrus (FG) in subjects with mild cognitive impairment (MCI) during performance of a face-matching task. The right middle FG is a key area for processing face stimuli. Brain activity was measured using functional MRI. There were 16 MCI subjects and 19 age-matched healthy controls. The linear correlation coefficient was utilized as a measure of functional connectivity between the right middle FG and all other voxels in the brain. There were no statistical differences found in task performance or activation between groups. The right middle FG of the healthy control and MCI groups showed strong bilateral positive linear correlation with the visual cortex, inferior and superior parietal lobules, dorsolateral prefrontal cortex (DLPFC) and anterior cingulate. The healthy controls showed higher positive linear correlation of the right middle FG to the visual cortex, parietal lobes and right DLPFC than the MCI group, whereas the latter had higher positive linear correlation in the left cuneus. In the healthy controls, the right middle FG had negative linear correlation with right medial frontal gyrus and superior temporal gyrus and with left inferior parietal lobule (IPL), angular gyrus, superior frontal gyrus and anterior cingulate gyrus, but the MCI group had negative linear correlation with the left IPL, angular gyrus, precuneus, anterior cingulate, and to right middle temporal gyrus and posterior cingulate gyrus. In the negatively linearly correlated regions, the MCI group had reduced functional connectivity to the frontal areas, right superior temporal gyrus and left IPL. Different regions of the cuneus and IPL had increased functional connectivity in either group. The putative presence of Alzheimer's disease neuropathology in MCI affects functional connectivity from the right middle FG to the visual areas and medial frontal areas. In addition, higher linear correlation in the MCI group in the parietal lobe may indicate the initial appearance of compensatory processes. The results demonstrate that functional connectivity can be an effective marker for the detection of changes in brain function in MCI subjects.