【摘要】 目的采用任务态功能MRI技术探讨脑卒中患者工作记忆障碍的神经病理机制。方法选择2013年8月～2016年5月北京博爱医院就诊的缺血性脑卒中患者24例(试验组),健康志愿者24例(对照组),所有被试者在执行2-back空间工作记忆任务时行功能MRI扫描,应用DPARSF及SPM12软件包对功能MRI数据进行预处理和统计分析。结果试验组在执行2-back空间工作记忆正确率明显低于对照组[(67.22±11.60)%vs(98.03±3.26)%,P<0.01],平均反应时间明显高于对照组[(1125±227)ms vs(843±112)ms,P<0.01]。试验组在空间2-back任务中双侧额中回、左侧顶下小叶及右侧小脑后叶区域的激活较对照组显著减弱(P<0.01),左侧边缘叶的前扣带回、右侧边缘叶的海马旁回、左侧楔前叶以及右侧中央前回区域的激活较对照组显著增强(P<0.05)。结论在执行工作记忆任务时工作记忆网络激活减弱而默认脑网络激活增强,这可能是脑卒中患者工作记忆障碍的一个重要的神经机制。更多还原

【Abstract】 Objective To study the neuropathological mechanism of working memory impairment(WMI) in stroke patients using task-state functional MRI(ts-fMRI).Methods Twenty-four ischemic stroke patients admitted to Beijing Boai Hospital from August 2013 to May 2016 served as an experimental group with 24 healthy volunteers served as a control group.The patients underwent fMRI scanning when they were performing a 2-back spatial WM task.The ts-fMRI parameters were preprocessed and computed with DPARSF and SPM12 software packages.Results The accuracy of 2-back spatial WM task was significantly lower while the mean reaction time of 2-back spatial WM task was significantly longer in experimental group than in control group(67.22%±11.60% vs 98.03%±3.26%,P<0.01;1125±227 ms vs 843±112 ms,P<0.01).The activation of bilateral middle frontal gyrus,left inferior parietal lobule and right cerebellar posterior lobe at bed side was significantly weaker while that of left limbic lobe anterior cingutate,right limbic lobe parahippocampal gyrus,left precuneus and right precentral gyrus was significantly stronger in experimental group than in control group when the 2-back spatial WM task was proformed(P<0.01,P<0.05).Conclusion The WM network is weakly activated and the default brain network is strongly activated when a 2-back spatial WM task is proformed,which may be considered as an important neural mechanism of WMI in stroke patients.更多还原