精神分裂症患者n-back工作记忆神经机制异常的ERP研究  

The Dysfunction During a Parametric N-back Task in Schizophrenia: An Event-related Potential Study

作　　者：王湘[1] 王晓晟[2] 王晓燕[3] 刘鼎 陈斌[5] 姚树桥[1] 

机构地区：[1]中南大学湘雅二医院医学心理研究中心,湖南长沙410011 [2]中南大学湘雅医学院人体解剖学与神经生物学系,湖南长沙410013 [3]海军总医院海军免疫卫生防疫队 [4]湘潭市中心医院心理诊疗科 [5]湖南省人民医院临床心理科

出　　处：《中国临床心理学杂志》2010年第3期269-273,共5页Chinese Journal of Clinical Psychology

基　　金：国家自然科学基金青年科学基金项目(30700236);教育部高等学校博士学科点专项科研基金新教师基金(20070533067)资助

摘　　要：目的:比较精神分裂症患者与正常人在参量变化的工作记忆负荷水平下所诱发的ERP成分及其脑区分布差异,探讨精神分裂症患者工作记忆功能损害的神经机制。方法:精神分裂症患者以及正常对照各20名参加了n-back(n=0,1,2)工作记忆任务的ERP实验,同时记录行为数据及EEG,离线处理数据。结果:精神分裂症患者在1-back及2-back任务中行为表现明显较正常人差(P<0.01)。正常人P3波幅随记忆负荷增长而成比例下降(0-back>1-back>2-back),而精神分裂症患者仅0-back的P3波幅显著高于1-back及2-back,(0-back>1-back=2-back)。三种负荷条件下,精神分裂症组中央区的P3峰值均显著高于正常组,而2-back条件下的顶区P3峰值显著高于正常组。高记忆负荷与低记忆负荷的任务相减均得到一差异波N450成分。在顶区,精神分裂症患者的1-0差异波N450成分的波幅显著高于正常组,而2-1差异波N450成分的波幅显著低于正常组(P<0.05)。结论:精神分裂症患者存在显著的工作记忆损害,其中短时贮存功能损害可能与患者顶叶的生理低效能及工作记忆容量下降有关。Objective： To examine the aberrant neurophysiological response during the parametric N-back task in schizophrenia,and investigate the dynamic dysfunction in the WM system of schizophrenia.Methods： 20 schizophrenic patients and 20 matched healthy controls performed a parametric n-back task with increasing working memory（WM） load（0-Back,1-Back and 2-Back）,while the EEG was recorded during they performed the task.Results： Schizophrenia performed significant poorly than normal subjects in 1-back and 2-back task（P〈0.01）.For controls,P3 peak amplitude decreased progressively as WM load increased（0-back 〉1-back〉 2-back）,while schizophrenic subjects showed no significant difference between the amplitude of P3 elicited in 1 and 2-back task（0-back〉1-back=2-back）.Moreover,the patient group showed larger P3 amplitude than that of controls in central region in 0,1,2-back task,and parietal region in 2-back task.The difference wave N450 appeared at the frontal and parietal areas by subtraction of ERP in the lower load task from the higher load task.Schizophrenia demonstrated an enhanced 1-0 difference wave N450 in parietal region compared with controls,but a reduced 2-1 difference wave N450 in the same region（P〈0.05）.Conclusion： Schizophrenia showed significant WM impairment.The short-term storage deficit in schizophrenia might be associated with the physiological inefficiency of parietal lobe and the reduced WM capacity.

关 键 词：精神分裂症 工作记忆 事件相关电位(event-related potential ERP) n-back范式 

分 类 号：R395.4[哲学宗教—心理学]