摘要目的 采用功能磁共振成像(fMRI)技术对正常中老年人进行研究,检测与词语联想功能相关脑区的激活特点.方法 采用GE 1.5 T磁共振扫描仪对23例(男12例,女11例)正常中老年人行组块设计的词语联想任务fMRI研究.采用SPM 2软件进行数据处理和统计分析,通过组分析获得平均脑激活图,观察脑激活区的部位和激活强度.结果 12例符合入组条件,激活脑区为运动前区(PMC)、双侧额下回后部(Broca区及Broca镜像区)、双侧辅助运动区(SMA)、左侧顶后皮层、双侧岛叶、双侧扣带回前部、双侧基底节、左侧丘脑以及右侧小脑半球.全脑以左侧PMC激活强度最大.激活强度左侧大于右侧的脑区为额下回后部、背侧PMC及SMA;右侧大于左侧的脑区为腹侧PMC、岛叶、扣带回前部、基底节.结论 中老年人参与运动性语言表达的脑区,由包括Broca区在内的多个脑区组成复杂的神经网络,且相关脑区存在偏侧化现象,以左侧大脑半球和右侧小脑半球激活为主.

abstractsObjective To detect brain areas related to word association of language expression and to summarize the characteristics of the active areas in the normal middle-aged and old subjects with function magnetic resonance imaging (fMRI). Methods Twenty-three middle-aged and old subjects were recruited in this study. All of them received block-designed fMRI with word association of language expression. GE 1.5 T Twin speed MR Scanner was used to obtain fMRI data. SPM 2 software was used to process fMRI data and to get the average activation maps. Location and activation degree were observed and recorded. Results Twelve subjects were admitted into the study. Activated regions included bilateral premotor cortex (PMC), bilateral posterior inferior frontal gyrus (Broca's area and Broca's mirror image), bilateral supplemental motor area (SMA), left posterior parietal cortex, bilateral insular lobe, bilateral anterior callosal gyrus, bilateral basal ganglions, left thalamus, and right cerebellum. Left PMC was the most activated area of whole brain. Left Broca's area, left dorsal PMC and SMA were more activated than corresponding contralateral areas. Right ventral PMC, insular lobe, anterior eallosal gyrus and basal ganglions were more activated than corresponding contralateral areas. Conclusions There are many brain areas associated with motor language expression function in the middle-aged and old people. A complex neural network is made up of the areas including Broca's area. Lateralization of the language expression areas presents in left hemisphere and right cerebellum prominence.