第二语言书写的功能神经影像学研究

The neural substrates underlying the writing-a second language PET study

目的探讨中国人以英语为第二语言进行书写的神经基础。方法利用PET—CT对6例健康受试者行假写作业和英语文字书写作业的18氟脱氧葡萄糖（18F—fluoro－2-deoxy—D—glucose，18F—FDG）脑功能成像，用统计参数图（Statistical parametric mapping，SPM）方法对假写、书写的脑PET图像进行配对t检验分析，获得英语文字书写引起的脑内葡萄糖代谢变化区域。结果左侧顶下小叶、中央后回、扣带回、壳核和右侧额上回、运动前回、丘脑背侧内核、小脑半球葡萄糖代谢增加（P〈0．05）。结论第二语言书写涉及多个脑区，左侧顶下小叶、右侧额叶及小脑半球参与词汇的产生和加工过程，左侧壳核在语言学习上发挥了一定的作用。

Objective To research the neural substracts for the processing of the discourse-level English writing using PET-CT. Method Six healthy people underwent 18F-FDG PET examination in the pseudo-writing condition and the discourse-level English writing condition, statistical parametric mapping（SPM） was used to investigate the activicated focus in english writing through pared- t test. Results The activated foci were observed in left inferior parietal lobule,left postcentral gyrus, left cingulate gyrus, left putamen, right frontal precentral gyrus, right superior frontal gyrus, right thalamus medial dorsal nucleus, both cerebellum （P 〈 0.05 ）. Conclusions The writing of English as a second language implicates cortical and subcortical structures. Left inferior parietal lobule, right frontal and both cerebellum participate in the language production and processes ,and left putamen is more en- gaged in English learuing.