维吾尔语和汉语动词产生相关脑区的功能性磁共振成像研究

目的通过功能性磁共振成像（fMRI）观察母语为维吾尔语（简称维语）和汉语正常人执行动词产生任务时的脑激活区及其脑激活差异区,探讨语言理解和产生的神经机制,以及脑损伤后语言障碍及其康复机制。 方法以维语和汉语名词为基本实验材料,通过血氧水平依赖功能性磁共振成像（BOLD-fMRI）扫描31例维吾尔族（语组）和28例汉族（汉语组）正常志愿者执行动词产生任务时的脑激活区,采集fMRI数据,并进行组内及组间比较。 结果汉语组的主要脑激活区为左侧尾状核、左侧枕下回、左侧梭状回、双侧辅助运动区（BA8/6区）、左侧BA32区、左侧楔前叶、左侧顶上、下小叶（BA7区）、左侧角回、右侧中央前回（BA9区）、左侧三角部额下回、右侧岛盖部额下回和双侧小脑。维语组的主要脑激活区为左侧中央前回（BA9区）、左侧岛盖部额下回、左侧三角部额下回和左侧小脑。维语组和汉语组组间比较发现,汉语组在左侧尾状核体、左侧眶部额中回、右侧尾状核头和双侧扣带回前部（BA32区）有明显激活,与维语组比较,差异有统计学意义（P<0.05）;而维语组未见比汉语组更明显激活的脑区。 结论维语和汉语正常人动词产生激活脑区不完全相同;维语文字的加工处理主要集中在左侧大脑半球;汉字加工处理比维语文字加工处理需要更多右侧大脑半球的参与。     

汉字情景记忆时皮层定位的fMRI研究

目的探讨用功能磁共振成像(fMRI)检测汉字情景记忆时皮层定位的价值及皮层定位的双侧不对称性.方法 10名健康右利手成人,以高频双字汉字作为刺激任务,行全脑fMRI,确定激活皮层的定位.结果汉字情景记忆时双侧多个脑区有激活,但两侧激活脑区不完全对称,编码加工时主要激活脑区为左侧纹外区和左侧颞叶梭状回,而提取加工时左侧顶叶楔前叶、左侧前额叶背外侧显著激活.结论汉字情景记忆时左右大脑半球激活区存在不对称性,fMRI可对此种功能皮层进行准确定位.     

熟练蒙汉双语者语义加工脑机制的fMRI分析

目的探讨熟练蒙汉双语者在蒙语和汉语语义信息加工的脑机制。方法对15右利手、蒙汉双语熟练的健康志愿者(男8名,女7名)进行fMRI测试,分析采用蒙语及汉语词语的语义判断任务。应用AFNI软件分析两种语言任务的脑功能激活情况及其差异。结果在汉语及蒙语语义信息加工过程中,语义加工的经典脑区均被激活,包括左侧颞中回、左侧后顶叶、左侧前额叶等区域。比较加工蒙语及汉语的语义信息过程,蒙语任务下左侧楔回及右侧梭状回的激活显著增加,汉语任务下在左侧颞中回后部、左侧额中回及额下回三角部、左侧顶上小叶的脑激活比蒙语显著增加。结论熟练蒙汉双语者在加工蒙语及汉语时,存在功能加工脑区的分离。fMRI研究能为双语者的语言加工脑机制提供影像学依据。     

汉语及图片语义加工机制的fMRI研究

目的利用功能磁共振成像(fMRI)技术探讨汉字及图片语义加工的脑机制。方法对13名正常青年受试者进行视觉方式呈现汉字及图片语义辨别任务的fMRI扫描,采用AFNI软件进行数据分析和脑功能区活动图像。结果fMRI显示两种任务均激活了左侧顶下小叶、额中回、额下回、右侧小脑及双侧梭状回、舌回、枕中回、枕下回、辅助运动区。其中左侧顶下小叶、额中回及双侧枕中回、梭状回在图片语义辨别任务激活明显强于汉字任务,有显著性差异(P<0.05)。结论汉字及图片语义的脑加工均存在偏侧化现象,图片语义的脑处理有更多的脑活动参与完成。     

汉字与英文字形辨认的脑功能磁共振成像初步研究

目的:探讨功能磁共振成像(fMRI)技术研究人脑汉字与英文字形辨认方面的价值。材料与方法:12例(男5例,女7例)母语为汉语且裸眼视力正常的大学生参加实验。设备为GE Signa 1.5T MR仪,采用EPI序列,BOLD法行脑功能磁共振扫描。实验任务分别将汉字与英文(真字、假字、非字)投射到屏幕上,受试者通过头线圈反光镜观看屏幕并辨认。数据分析使用SPM 99升级软件,经过数据采集、预处理和建立模型显示结果。结果:汉字真字刺激在左额叶、中央前回(BA6)及枕叶(BA18)显著激活;左顶叶、中央后回(BA3)、右额下回(BA9)及双侧颞叶少量激活。英文真字刺激时左额中回、中央前回、左额下回显著激活;左颞梭状回(BA37)、右枕语言回(BA18)及左顶叶(BA40)也有激活。汉字和英文假字与非字只引起少量激活(P>0.05)。汉字与英文刺激左大脑半球的激活体积明显大于右半球;除枕叶外,英文在额、颞及顶叶引起的激活体积均大于汉字。结论:fMRI是研究人脑汉字和英文语言加工理想的无创性影像学方法,其脑加工优势半球均为左半球;母语为汉语者,其英文脑处理过程需更多的脑活动来参与和完成。     

维吾尔语和汉语两种语言任务激活脑区差异性的fMRI研究

目的探索母语为维吾尔语(维语)和汉语健康人在执行语义辨别和动词产生两种语言任务时的脑激活差异区,并初步探讨维语脑加工处理机制。 方法采用血氧水平依赖性功能磁共振成像（BOLD-fMRI）技术,采集15例维吾尔语健康志愿者（维语组）和15例汉语健康志愿者（汉语组）执行语义辨别和动词产生两种语言任务时的fMRI数据,并进行2组数据统计学比较。 结果语义辨别任务时,维语组左侧扣带回（BA23）和中线处楔前叶等局部脑区可见明显的正激活,与汉语组相比,差异有统计学意义（P<0.05）。动词产生任务时,维语组左侧颞下回（BA37）、顶下小叶、梭状回和海马旁回等局部脑区可见明显激活,与汉语组相比,差异有统计学意义（P<0.05）;汉语组则在右侧颞上回（BA38）可见明显的激活,与维语组相比,差异有统计学意义（P<0.05）。 结论维语和汉语语义辨别和动词产生激活脑区不完全相同,左侧扣带回在维语语义加工中可能更多参与语音加工;汉字加工处理可能比维文加工有更多的右半球参与。     

左脑前额叶与语言神经机制的功能影像学研究

目的 利用Fmri研究大脑左半球前额叶特别是前额叶中、下回(Brodmann 9/46或者BA9/46)在汉语加工中的神经机制.方法 选取18名不同被试,运用1.5T Siemens Symphony磁共振成像机器,使用不同的现代汉语四字词组作为语言认知刺激材料进行脑功能成像扫描.结果 功能性磁共振成像结果显示左脑额叶在词组加工中激活明显,大脑左侧额中回(Talairach坐标:-42,12,17)以及左侧额下回(Talairach坐标-44,13,17)是激活最大脑区的中心位置.结论 不但汉语单个字或者词的神经加工机制需要左脑前额叶的参与,词组理解加工同样也需要左脑前额叶,特别是BA9、BA46的参与.实验任务较多关注语义理解,则表明BA9、BA46可能更多与语义理解相关.     

针刺大钟穴激活脑区的功能MRI研究

目的：探讨应用功能MRI (fMRI)针刺大钟穴对脑的激活效应。材料与方法选取12名健康青年志愿者。分别针刺受试者右侧大钟穴(络穴),同时应用3.0T MR扫描仪完成脑部扫描。所获得的实验数据采用统计参数图软件SPM8(statistical parametric mapping)分析处理。结果针刺受试者大钟穴,激活的脑区有双侧小脑前叶,左侧颞下回BA37,左侧颞中回BA38、BA39,左侧颞极BA38,右侧颞极BA32,左侧脑干,左侧苍白球,右侧额中回BA6,左侧额上回BA6。结论大钟穴的脑激活区主要分布在额叶、颞叶、小脑前叶及脑干和苍白球,它们的主要功能是负责躯体感觉冲动的传入,与足跟痛及腰腿痛的脑内躯体感觉中枢相符合。     

功能磁共振成像观察吸烟成瘾者对香烟的嗅觉诱导反应

目的 观察吸烟成瘾者在不同生理状态下以及吸烟成瘾者与非吸烟者接受香烟嗅觉刺激时引起脑功能区的不同激活模式.方法 17名右利手受试者(非吸烟对照组5名,吸烟成瘾者12名)完成试验.采用Block设计,EPI采集,以烟卷作为嗅觉暗示任务,纸卷作为对照物.结果 12名吸烟成瘾者在戒断状态下面对香烟嗅觉诱导刺激时,左侧额上回(BA8、9、10、11)、右侧额上回(BA10)、左侧额中回(BA8、10、11、46)、右侧额中回(BA8、9)、左侧额下回(BA9)、右侧额下回(BA45、47)、左侧额内侧回(BA6、8、10、11)、右侧额内侧回(BA9、11)、左侧扣带回(BA24、31)、右侧扣带回(BA24、37)、右侧颞中回(BA21)及双侧丘脑及小脑半球激活;在满足状态下,双侧前额叶、双侧小脑半球亦见激活,而其他脑区未见明显激活.非吸烟者面对香烟刺激时全脑未见明显激活,仅1名受试者出现少数小体积激活点,考虑由图像噪声引起.结论 前额叶、中脑边缘系统(扣带回前部及后部、丘脑)在通过鼻腔给予香烟嗅觉刺激所诱导的吸烟渴望神经机制中发挥重要作用;在临床型1.5T MR成像设备上,利用鼻腔通路,通过香烟嗅觉诱导刺激观察和研究吸烟成瘾者的相关脑激活区以及神经环路与作用机制是可行的.     

针刺丰隆穴脑激活区功能磁共振成像研究

目的应用血氧水平依赖功能磁共振成像(Bold-fMRI)技术,探讨针刺丰隆穴脑效应机制。材料与方法按照纳入标准,对16名受试者右侧丰隆穴及非穴进行针刺并采集fMRI数据,利用DPARSF、统计参数图(SPM12)及XJVIEW软件进行数据预处理和统计分析。结果相比非穴,针刺丰隆穴增强脑激活区包括:右侧额下回(BA45)、顶上小叶(BA7),左侧顶下小叶(BA40);减弱脑激活区包括:右侧边缘叶、丘脑、前扣带回(BA32)、额中回(BA46)、小脑后叶,左侧海马旁回(BA35)、脑岛(BA13)、小脑前叶。结论针刺丰隆穴与非穴比较脑激活区具有相对特异性,这些脑区与认知、痛觉处理等功能相关。     

未受教育及受教育儿童语言处理脑区偏侧化的差异:基于体素的MR形态学分析

目的采用基于体素的形态学方法分析未受教育及受教育儿童语言处理相关脑区的偏侧化差异。方法对42名学龄儿童(未受教育组23名,6.0～7.8岁,中位年龄6.5岁;受教育组19名,5.8～7.6岁,中位年龄6.3岁)行高分辨力T1W扫描,采用VBM8软件包进行图像后处理,并采用LI-tools工具软件进行偏侧化分析,比较未受教育组与受教育组的灰质密度(GMD)偏侧化指数情况。结果受教育组的额下回(BA44)以及颞上回(BA22)的GMD偏侧化指数显著高于未受教育组。结论学校教育可能显著促进额下回和颞上回的GMD偏侧化。     

Developmental changes in brain regions involved in phonological and orthographic processing during spoken language processing

Developmental differences in brain activation of 9- to 15-year-old children were examined during an auditory rhyme decision task to spoken words using functional magnetic resonance imaging (fMRI). As a group, children showed activation in the left superior/middle temporal gyri (BA 22, 21), right middle temporal gyrus (BA 21), dorsal (BA 45, pars opercularis) and ventral (BA 46, pars triangularis) aspects of the left inferior frontal gyrus, and left fusiform gyrus (BA 37). There was a developmental increase in activation in the left middle temporal gyrus (BA 22) across all lexical conditions, suggesting that automatic semantic processing increases with age regardless of task demands. Activation in the left dorsal inferior frontal gyrus also showed developmental increases for the conflicting (e.g. PINT-MINT) compared to the non-conflicting (e.g. PRESS-LIST) non-rhyming conditions, indicating that this area becomes increasingly involved in strategic phonological processing in the face of conflicting orthographic and phonological representations. Left inferior temporal/fusiform gyrus (BA 37) activation was also greater for the conflicting (e.g. PINT-MINT) condition, and a developmental increase was found in the positive relationship between individuals' reaction time and activation in the left lingual/fusiform gyrus (BA 18) in this condition, indicating an age-related increase in the association between longer reaction times and greater visual-orthographic processing in this conflicting condition. These results suggest that orthographic processing is automatically engaged by children in a task that does not require access to orthographic information for correct performance, especially when orthographic and phonological representations conflict, and especially for longer response latencies in older children.     

阅读半规则汉字时的脑激活模式:声调的作用

目的引入声调因素,运用功能磁共振成像技术进一步研究汉字规则性效应的脑激活模式.方法13名被试在磁共振扫描过程中执行视觉方式呈现的汉字出声阅读任务,根据形声字声旁与整字间读音及声调相同与否,将刺激材料细分为同音同调字、同音异调字、异音同调字和异音异调字,每类20字.结果四种条件均激活双侧额中回、额下回、前运动区及辅助运动区、左侧顶下小叶、双侧颞上回、双侧岛叶和右侧小脑,同时还各自激活了梭状回、颞中回、左内侧额叶等区域.另外,本实验还观察到这四种条件在右侧颞上回、双侧额下回等区域激活模式的特征性变化.结论存在汉字加工的半规则效应,声调的作用不应忽略.     

A meta-analysis of fMRI studies on Chinese orthographic, phonological, and semantic processing

A growing body of neuroimaging evidence has shown that Chinese character processing recruits differential activation from alphabetic languages due to its unique linguistic features. As more investigations on Chinese character processing have recently become available, we applied a meta-analytic approach to summarize previous findings and examined the neural networks for orthographic, phonological, and semantic processing of Chinese characters independently. The activation likelihood estimation (ALE) method was used to analyze eight studies in the orthographic task category, eleven in the phonological and fifteen in the semantic task categories. Converging activation among three language-processing components was found in the left middle frontal gyrus, the left superior parietal lobule and the left mid-fusiform gyrus, suggesting a common sub-network underlying the character recognition process regardless of the task nature. With increasing task demands, the left inferior parietal lobule and the right superior temporal gyrus were specialized for phonological processing, while the left middle temporal gyrus was involved in semantic processing. Functional dissociation was identified in the left inferior frontal gyrus, with the posterior dorsal part for phonological processing and the anterior ventral part for semantic processing. Moreover, bilateral involvement of the ventral occipito-temporal regions was found for both phonological and semantic processing. The results provide better understanding of the neural networks underlying Chinese orthographic, phonological, and semantic processing, and consolidate the findings of additional recruitment of the left middle frontal gyrus and the right fusiform gyrus for Chinese character processing as compared with the universal language network that has been based on alphabetic languages.     

Overlap and dissociation of semantic processing of Chinese characters, English words, and pictures: evidence from fMRI

The functional anatomy of Chinese character processing was investigated using fMRI. Right-handed Mandarin-English bilingual participants made either semantic or perceptual size judgements with characters and pictures. Areas jointly activated by character and picture semantic tasks compared to size judgement tasks included the left prefrontal region (BA 9, 44, 45), left posterior temporal, left fusiform, and left parietal regions. Character processing produced greater activation than picture processing in the left mid and posterior temporal as well as left prefrontal regions. The lateral occipital regions were more active during picture semantic processing than character semantic processing. A similar pattern of activation and contrasts was observed when English words and pictures were compared in another set of bilingual participants. However, there was less contrast between word and picture semantic processing than between character and picture processing in the left prefrontal region. When character and word semantic processing were compared directly in a third group, the loci of activation peaks was similar in both languages but Chinese character semantic processing was associated with a larger MR signal change. The semantic processing of Chinese characters, English words, and pictures activates a common semantic system within which there are modality-specific differences. The semantic processing of Chinese characters more closely resembles English words than pictures.     

Developmental changes in the neural correlates of semantic processing

Functional magnetic resonance imaging (fMRI) was used to explore the neural correlates of semantic judgments in the auditory modality in a group of 9- to 15-year-old children. Subjects were required to indicate if word pairs were related in meaning. Consistent with previous findings in adults, children showed activation in bilateral superior temporal gyri (BA 22) for recognizing spoken words as well as activations in bilateral inferior frontal gyri (BAs 47, 45) and left middle temporal gyrus (BA 21) for semantic processing. The neural substrates of semantic association and age differences were also investigated. Words with strong semantic association elicited significantly greater activation in the left inferior parietal lobule (BA 40), whereas words with weak semantic association elicited activation in left inferior frontal gyrus (BAs 47/45). Correlations with age were observed in the left middle temporal gyrus (BA 21) and the right inferior frontal gyrus (BA 47). The pattern of results for semantic association implies that the left inferior parietal lobule effectively integrates highly related semantic features and the left inferior frontal gyrus becomes more active for words that require a greater search for semantic associations. The developmental results suggest that older children recruit the right inferior frontal gyrus as they conduct a broader semantic search and the left middle temporal gyrus to provide more efficient access to semantic representations.