摘要目的 观察早、晚期双语者进行第二语言书写时的脑激活区并探讨其神经心理学机制.方法 12名受试者分为早、晚期习得高熟练程度双语组,分别执行假写和英语书写作业,进行功能成像后分别对两组的假写和英语书写的图像数据进行配对t检验,并对两组进行联合分析,分析葡萄糖代谢变化的区域,获得相应的脑功能激活图.结果 早期习得高熟练程度英语书写组葡萄糖代谢增加脑区:双侧额中回(Z=4.35/2.01)、双侧小脑(Z=2.97/2.53)、左侧尾状核头(Z=3.07)等;晚期习得高熟练程度英语书写组葡萄糖代谢增加脑区:右侧额上回(Z=4.06)、右侧小脑(Z=4.63)、左侧壳核(Z=2.70)等;晚期习得高熟练程度组和早期习得高熟练程度组比较葡萄糖代谢增加脑区:右侧额回(Z=2.92)、右侧颞叶(Z=2.31)等.本试验所获数据差异有显著性(P＜0.05).结论 广泛脑皮层、皮层下结构参与第二语言的书写过程.语言习得年龄是影响第二语言书写脑功能定位的因素之一.

abstractsObjective To observe activated cerebral areas during the task of writing in second language by early and late acquisition bilinguals and explore the neuropsychological mechanism. Methods Twelve subjects were divided into group of early acquisition high proficiency bilinguals(EAHP) and group of late acquisition high proficiency bilinguals(LAHP). Each subject carried out the task of pseudo-writing and English writing. After functional imaging,statistical parametric mapping was used to compare data of the two tasks through paired- t test in both two groups. A conjunction analysis was conducted between the two groups also. Areas where the metabolism of glucose changed were analyzed. Then, the corresponding images about activated cerebral regions were obtained.Results Cerebral areas where the metabolism of glucose increased in EAHP: bilateral middle frontal gyrus( Z=4.35/2. 01 ), bilateral cerebellum ( Z = 2.97/2.53 ) and left head of caudate nucleus ( Z = 3.07 ), etc. Cerebral areas where the metabolism of glucose increased in LAHP: right superior frontal gyrus(Z=4.06), right cerebellum( Z=4.63), left putamen(Z=2.70) ,etc. Cerebral areas where the metabolism of glucose increased in compared data of LAHP with data of EAHP: right frontal gyrus ( Z = 2.92 ), right temporal lobe( Z = 2.31 ), etc. Conclusion Extensive cerebral cortex and subcortical structures participate the process of writing in the second language. Age of bilingual acquisition is one of the factors affecting cerebral localization of writing in second language.