正常人丘脑及岛盖功能连接的MRI研究

Functional magnetic resonance imaging of brain functional connectivity for thalamus and opercular

目的:探讨正常人在静息和认知任务状态下丘脑及岛盖功能连接的变化情况。方法:采用BOLD-fMRI方法,检测16例健康志愿者在静息和2-back任务状态下的脑功能连接,将前额叶内侧皮层作为种子点,应用SPM2、AFNI及Matlab软件进行图像数据处理,对2-back任务和静息状态行组内和组间2个水平的统计分析,统计阈值概率设定为P=0.005(未校正)。结果:与左侧丘脑前核相关的网络系统与默认网络一致,而丘脑背侧部属"任务正激活网络",且受试者反应正确率与左侧丘脑背侧的相关性差异有统计学意义(r=-0.52,P=0.04)。"岛盖相关网络"与"默认网络"呈负相关,前者在静息状态相关性高于任务状态,其主要脑区包括双岛叶、双顶下小叶、双中央旁小叶、双颞上回、双海马旁回等。结论:人脑在静息和任务状态下脑区间的功能连接不同,表现为丘脑前核和丘脑背侧部的功能分化,及"岛盖相关网络"与"默认网络"在静息状态的功能拮抗。

Objective：To investigate the functional connectivity changes of thalamus and opercular based on resting state and cognitive task using functional magnetic resonance imaging.Methods：Sixteen normal subjects received blood oxygenation level dependent functional magnetic resonance imaging（BOLD-fMRI）examinations based on resting state and digital 2-back working memory task.The fMRI data were processed and analyzed with SPM2,AFNI and Matlab software packages（thresholded at P=0.005,uncorrected）.Medial prefrontal cortex（MPFC,BA10）was placed as region of interest.Results：The network related with left anterior nucleus thalamus was consistent with default mode network.The medial dorsal thalamus was a part of＂ task-positive network＂.The correlation between the reaction accuracy[（89.89±8.05）%]and the left medial dorsal thalamus had statistical significance（r=-0.52,P=0.04）.The＂opercular related network＂negatively correlated with default mode network and the correlation coefficient was higher in resting state than that in 2-back task.Its brain areas included the bilateral insula/superior temporal gyrus（BA22）,inferior parietal lobule（BA40）,paracentral lobule and parahippocampus.Conclusion： The functional connectivity of human brain is different in resting state and cognitive task.The functional specialization is observed between the anterior nucleus thalamus and medial dorsal thalamus.Functional antagonism lies in the＂opercular related network＂and default mode network in the resting state.