语义判断中选择与抑制机制的功能MRI研究  

Functional MRI studies of the neural mechanisms of selection and inhibition in Chinese semantic judgement

作　　者：郝晶[1] 李坤成[1] 王岩[2] 陈骐[2] 彭晓哲[2] 周晓林[2] 

机构地区：[1]首都医科大学宣武医院医学影像学部放射科,北京100053 [2]北京大学脑科学与认知科学中心北京大学心理学系

出　　处：《中国医学影像技术》2004年第2期223-226,共4页Chinese Journal of Medical Imaging Technology

摘　　要：目的　采用事件相关功能磁共振成像 (event relatedfunctionalMRI ,ER fMRI)技术 ,探讨汉语语义判断任务中选择、抑制机制的神经基础。方法　对 9例右利手的健康成人进行了侧抑制任务 (flankertask)与汉语语义判断任务相结合的实验测试 ,同时采用 1.5T磁共振成像系统 ,采集其脑部的BOLD fMRI数据 ,通过AFNI软件进行统计分析 ,得到脑功能活动的图像。结果　①语义选择的相关脑区包括右侧额上回 (BA 6区 )、右侧扣带回、左侧额中回 (BA 9区 )、双侧运动区和运动前区、左侧顶下小叶 ;②负责语义判断抑制功能的脑区主要有右侧额中回和左侧额下回。此外 ,随任务难度增大 ,前扣带回激活 ,而且从以右半球激活为主过渡到以左半球激活为主。结论　ER fMRI可以对语义判断任务中选择、抑制机制的有关大脑皮层区进行定位 ,是研究高级认知活动神经基础的重要手段。Objective To identify the neural mechanisms of selection and inhibition in the Chinese semantic judgement with event-related functional MRI (ER-fMRI).Methods Nine right-handed healthy adults participated in the experiment designed with flanker task and Chinese semantic judgement task.The fMRI data were collected on 1.5 T MRI systems and analyzed by AFNI to generate the activation maps.Results ①The functional localizations of the selection of semantic task included BA 6 area in the right superior frontal gyrus,right cingulated gyrus,left middle frontal gyrus (BA 9 area),bilateral motor areas and premotor areas and left inferior parietal lobule.②Activation within the right middle frontal gyrus and left inferior frontal gyrus was mainly correlated with the ability to resolve interference efficiently.As difficulty of the task increased,the anterior cingulated cortex (ACC) was engaged.And the activated mapping transformed from the right hemisphere to the left.Conclusion ER-fMRI is a valuable technique in establishing the neural mechanisms of higher-level cognitive process.It can map the functional localizations of the selection and inhibition of Chinese semantic judgement.

关 键 词：语义判断 侧抑制效应 磁共振成像 功能性 脑 

分 类 号：R338.25[医药卫生—人体生理学] R445.2[医药卫生—基础医学]