摘要
目的探究工作记忆容量（WMC）与回返抑制（BI）的相互关系，结合事件相关电位（ERP）时空模式考察BI产生的时间和相关脑区。方法24名受试者先进行延迟匹配样本任务测量WMC，再行3种线索提示下的数字属性判断任务：质数或合数、奇数或偶数、大于5或小于5，受试者以左右手按键判断，ABA类型的重复序列或CBA类型的非重复序列分别构成测试与对照任务，同步记录ERP。对高低容量组各9人的行为数据和ERP分别进行统计分析。结果24名受试者WMC的K分值为（4．13±1．02）分；高容量组BI效应显著高于低容量组（t（16）=2．345，P=0．032）；正确率差异无显著性（t（16）=0．738，P=0．471）。ERP的，值统计参数映像提示容量与任务的显著交互效应发生在-390--370ms和250～290ms的额顶区。结论BI效应受工作记忆容量影响，高容量者BI效应更大；回返抑制可能产生于线索（-390～-370ms）和刺激（250～290ms）评价两个阶段，相关脑区恰好同工作记忆涉及区域重叠。
Objective To explore the relationship between backward inhibition （BI） effect and working memory capacity （WMC） and the mechanism of BI with spatio-temporal patterns of event-related potentials. Methods Twenty-four subjects firstly took the delayed match-to-sample task to determine WMC. Each subject was divided into either high or low capacity group. Afterwards subjects took tasks of the digit properties judgment with different cues ： prime or composite, odd or even, more or less than five. ERP and behavioral performances of ABA-type task sequence,CBA-type task sequence were analyzed respectively. Eighteen subjects entered the final analysis and distributed to the low and the high by their WMC evenly. Results The K-WMC mean score of 24 subjects was（4.13 ± 1.02） , and date from 18 subjects entered into statistical analysis. No significant difference of correction rate was found between two groups（t 〈16） =0. 738, P=0. 471 ） , except for the value of BI effect. The high WMC group had higher BI effect significantly （t 〈0 05.16） = 2. 345, P= 0. 032）. Statistical parametric mapping of Fvalue of ERP suggested significant interactions between WMC and BI exist during two periods ： from - 390 - - 370 ms （ before target） and from 250 - 290 ms and involve similar bilateral frontal and parietal lobes. Conclusion BI effect involved frontal and parietal network in both cue and stimulus evaluation, which overlapped with the brain regions of working memory.
出处
《中国行为医学科学》
CSCD
2008年第12期1086-1088,共3页
Chinese Journal of Behavioral Medical Science
关键词
回返抑制
工作记忆容量
事件相关电位
Backward inhibition
Working memory capacity
Event-related potential
