正常国人音节任务的语言功能脑区的fMRI研究

The fMRI research of the syllabic task of the linguistic funition on cerebral area in healthy Chinese individuals

目的：运用事件相关删研究正常人语言功能脑区，明确性别、年龄对语言功能脑区的影响，并观察是否存在语言功能脑区的半球优势。方法：52名母语为汉语的右利手健康志愿者参加了实验，其中男26名，女26名，年龄20岁。65岁，平均年龄43．9岁。按照年龄和性别分为以下各组：≤50岁男性组（A组）、≤50岁女性组（B组）、〉50岁男性组（C组）和〉50岁女性组（D组）。每组中每名受试者分别完成默读“i”、朗读“i”两种任务。刺激采用视觉呈现。结果：不同性别和年龄的正常人的语言功能脑区激活体素和强度变化率差别无统计学意义，主要包括双侧额、颞、顶、枕叶和小脑半球；双侧对称激活区的体素和强度变化率差别无统计学意义；两种任务激活的语言功能脑区不尽相同，朗读任务激活的脑区较默读任务激活的脑区多，但各种任务激活的相同脑区的体素和强度变化率差别无统计学意义。结论：对于母语为汉语的正常国人，性别和年龄对语言功能脑区没有影响；语言功能脑区为双侧均势，未发现语言优势半球的存在，有别于西方文字的左侧半球优势现象；默读任务并不能可靠地激活语言功能脑区，尽管二者共同激活区的体素和强度变化率差别无统计学意义，但朗读任务激活的脑区较默读任务激活的脑区多，采用朗读方式研究人类语言功能脑区的方法应更合适。

Objective：To observe the linguistic-functional cortex so as to identify the effect of age and sex on normal language processing by ER-fMRI and to observe wbether a left or right predonrinance for lingulstic-functional cortex exits or not. Methods：We examined 52 healthy volunteers of 20-65 years old, of whom 26 are male and 26 are female. The average age is 43.9. All of the subjects, being Chinese and right-hand dominant, have got through the primary school education at least. We divided all file subjects into 4 groups according to their gender and age as follows： Group A, male, younger than 50 （including 50） ; Croup B, female, younger than 50 （including 50） ; Croup C, male, older than 50;Group D, female, older than 50. Each subject in groups finished 2 tasks, to read ＂i＂ loudly or silently. The occurrence of stimulus turned up in a way of visual presentation. Results：There were no statistical differences about the activated voxel and intensity change in the linguistically functional cortex between healthy male and female individuals of different decades. The activated areas include bilateral frontal lobe, temporal lobe, parietal lobe, occipital lobe and bilateral cerebellar hemisphere. Aceording to the matched-pairs design text, there were no statistical differences of the activated voxel and intensity change in bilateral activated areas. Although the activated areas were not quite the same when each of the above two tasks were being performed and more activation elicited by overt-reading titan that of covert-reading were observed, there was no statistical difference of the activated voxel and intensity change in the same activated areas of each task. Conclusion： Tbere were no age and gender differences in linguistic-function regions of healthy individual whose native language is Chinese. It is bilateral-equilibrium and no linguistic hemisphere＇ s predominance exits. This characteristic is different from the left-hemisphere dominance of westem languages. Although there were no statistical differences of the activated voxel and intensity change between overt-reading and covert-reading, more activation elicited by overt-reading than that of covert-reading were observed. Tbe way of overt-reading are more proper to some extent than that of covert-reading to study the lingnistie- function regions of human brain.