汪文静 尹世敏 黄玲

[摘要] 目的 比较2型糖尿病患者与正常人在三种工作记忆（working memory，WM）负荷水平下所诱发的事件相关电位（event-related potentials，ERPs）成分及其脑区分布差异，分析其事件相关电位的特点，讨论2型糖尿病患者工作记忆损害的神经机制。 方法 选取2012年6月～2013年10月期间火箭军总医院神經内科及内分泌科门诊和住院患者，筛选出2型糖尿病患者40例（男19例，女21例，最大年龄75岁，最小年龄55岁，平均67.45±7.82岁）。同时筛选出正常对照组40例（男18例，女22例，最大年龄75岁，最小年龄55岁，平均68.85±7.10岁），年龄、性别等相匹配。两组受试者均行n-back试验（n=0，1，2）工作记忆任务的ERPs试验，随着记忆负荷的增加，难度逐渐增大。记录脑电变化，离线分析数据。 结果 三种不同的记忆负荷水平均出现了P300成分，其变化在额叶显著。两组比较，0-back时，2型糖尿病组P300潜伏期较对照组延长，1-back时，2型糖尿病组波幅较对照组降低，差异有统计学意义。 结论 通过对三种记忆负荷水平下事件相关电位的研究，表明2型糖尿病患者存在工作记忆受损，而这种表现在额叶最为明显，提示额叶在工作记忆的处理过程中起重要作用。

[关键词] 2型糖尿病；工作记忆；事件相关电位；n-back试验

[中图分类号] R741.044 [文献标识码] B [文章编号] 1673-9701（2018）25-0109-03

[Abstract] Objective To compare the differences of event-related potentials（ERPs） and distribution of brain regions in the patients with type 2 diabetes and healthy people under three working memory（WM） stress levels， to analyze the characteristics of its event-related potentials， and to discuss the neural mechanism of working memory impairment in the patients with type 2 diabetes. Methods Patients hospitalized in the Department of Neurology and Endocrinology in the PLA Rocket Force General Hospital from June 2012 to October 2013 were selected. 40 patients with type 2 diabetes were screened（19 males， 21 females， with the largest age of 75 years old， the minimum age of 55 years old， and the average age of 67.45±7.82 years old）. At the same time， 40 healthy controls were screened（18 males， 22 females， with the largest age of 75 years old， the minimum age of 55 years old， and the average age of 68.85±7.10 years old）. Their age， gender and other factors were matched. Both groups of subjects were given n-back test（n=0， 1， 2） and ERPs test of working memory task. As the memory load was increased， the difficulty was increased. EEG changes were recorded and the data were analyzed offline. Results P300 components were detected in three different memory load levels. The change was significant in the frontal lobe. In the two groups， the P300 latency was longer in the type 2 diabetes group than in the control group at 0-back. At 1-back， the amplitude in the type 2 diabetes group was lower than that in the control group， and the difference was statistically significant. Conclusion The study of event-related potentials at three levels of memory load indicates that working memory is impaired in patients with type 2 diabetes. This manifestation is most significant in the frontal lobe， suggesting that the frontal lobe plays an important role in the processing of working memory.

[Key words] Type 2 diabetes； Working memory； Event-related potentials（ERPs）； n-back test

2型糖尿病（type 2 diabetes mellitus，T2DM）患者患阿尔茨海默病（Alzheimer disease，AD）及血管性癡呆（Vascular dementia，VD）的风险大大增加，其明确的发病原因还未完全被发现，还缺乏有效、特异的诊断、治疗及预防方法。其引起的认知功能障碍，主要表现在工作记忆（working memory，WM）[1，2]、额叶执行功能[3]、言语记忆[4-5]、词语流畅性等方面。Baddeley提出了工作记忆的概念，指出其是一种对信息进行暂时加工和贮存的能量有限的记忆系统[6]。……