中文摘要：

目的比较缺陷型、非缺陷型精神分裂症患者与执行控制功能有关的脑区激活情况,探讨精神分裂症执行功能障碍的表现规律与相应脑机制。方法缺陷型、非缺陷型精神分裂症患者各6名及与之匹配的正常对照组,在执行参量设计的倒数n项实验时进行全脑BOLD-fMRI扫描。数据处理时采用单因素方差分析进行差异检测,分离出激活强度随记忆负荷增加而增强的脑区（执行加工相关脑区）。结果正常组执行加工相关脑区主要为左侧前额叶及顶叶后部皮层,两精神分裂症组前额叶激活体积相对较小,而且涉及更多皮层下结构。其中非缺陷型组双侧前额皮层均显著激活,且背外侧前额叶（BA9/46区）激活数目较正常组明显增多。而缺陷型组无论是前额皮层激活的脑区分布范围还是体积均显著减少于其他两组。结论精神分裂症患者存在以前额叶功能失调为基础的执行功能障碍。不同亚型的患者前额叶功能失调的机制不同：缺陷型患者前额叶可能存在特异性损伤,而非缺陷型患者主要表现为前额叶的生理低效能。

英文摘要：

　Objective To compare the differences in brain activation patterns in deficit and nondeficit schizophrenia under parametric increasing WM load, and investigate the executive function impairment and the mechanism in deficit and nondeficit schizophrenia. Methods Six schizophrenic patients with deficit syndrome, matched nondeficit schizophrenic patients and healthy control subjects were studied in a parametric fMRI design of n-back task. One-way ANOVA was used to examine the WM-load-dependent changes of activity in brain regions （executive function related area）. Results The results showed significant WM load-depended increases in left prefrontal and posterior parietal cortex in controls. In patients with schizophrenia, there was less activity voxels in prefrontal cortex, but more significant activity in subcerebral structures. The nondeficit patients showed more obvious activity in dorsolateral prefrontal regions （DLPFC） and right prefrontal cortex than normal subjects. However, the deficit patients showed significant hypofrontality with less active areas and weaker activity in prefrontal lobe. Conclusion We conclude that schizophrenia have significant prefrontal lobe dysfunction and abnormal executive function. Moreover, there were differences between deficit and nondeficit patients in the activity patterns of prefrontal lobe and underlying neural mechanism. Deficit schizophrenia may have characteristic impairment of prefrontal lobe, whereas nondeficit schizophrenia showed relatively hyperfrontality and neurophysiological inefficiency.