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1.
目的 探讨慢性失眠患者数字工作记忆神经网络连接的改变.方法 采用组块设计方法,分别对40例慢性失眠患者(失眠组)及50例正常睡眠者(对照组)进行数字工作记忆状态下功能磁共振扫描,比较两组受试者在数字工作记忆中反应时间及正确率以及编码、维持、提取阶段脑区激活强度的改变.结果 失眠组与对照组数字工作记忆正确率的比较差异无统计学意义(P>0.05),失眠组反应时间明显增加,差异有统计学意义(P<0.01).慢性失眠患者在数字工作记忆编码期激活强度增强的脑区为左侧壳核、豆状核、顶下小叶及右侧尾状核、右枕叶;维持期激活强度增强的脑区为右侧额叶,左侧额叶及额叶内侧面,而左侧额上回激活强度有所下降;提取期激活强度增强的脑区为右额下回及右顶下缘角回,而激活轻度下降的脑区则有左内侧额上回、左岛叶、左后扣带回、左颞上回、左额上回及右颞叶、右后扣带回.结论 慢性失眠患者在数字工作记忆的各阶段,脑区激活强度较健康人有所改变:大脑皮质和皮质下结构广泛受损,即其神经网络连接发生明显改变.  相似文献   

2.
语义记忆脑功能区偏侧化的功能磁共振成像研究   总被引:1,自引:0,他引:1  
目的 通过功能磁共振成像(fMRI)技术检测健康人脑语义记忆功能区的分布特点.方法 14名右利手健康志愿者进行配对词语联想学习记忆任务时行fMRI扫描,该任务可有代表性地反映受试者的语义记忆.实验采用组块设计并选用SPM99软件行数据分析和脑功能区定位,记录各激活脑区的像素值并计算偏侧化指数LI值.结果 经单样本t检验,阈值设为P<0.005时,记忆编码时主要激活脑区为左枕叶和左额上中回,提取时主要激活左顶叶、左枕叶和左额中下回;而右半球在两阶段均较少激活.编码和提取激活脑区像素值LI值分别为0.81和0.73.结论 语义记忆的脑功能区有显著的左半球优势;记忆编码和提取阶段所激活的脑区有所差别,但均主要分布于左外侧裂语言区的周围.  相似文献   

3.
目的探讨正常人汉字任务下脑激活区的改变。方法对40例正常人进行汉字工作记忆功能磁共振扫描。结果汉字工作记忆任务下,编码、保持及提取期均有额叶、楔前叶、楔叶、边缘叶及扣带回的正向激活,且有侧脑室及脑脊液在编码及保持期的正向激活和在提取期的负向激活。除共同激活脑区外,编码期所有激活脑区均为正向激活,保持期正向激活脑区有中央前回、杏仁核、上后扣带皮层(BA 31),负向激活脑区有颞中回、顶叶、角回,提取期正向激活脑区有尾状核。结论汉字任务下,脑激活区的改变除皮层及皮层下结构,还有侧脑室及脑脊液的激活。  相似文献   

4.
目的本实验拟通过功能磁共振研究参与正常人空间记忆广度任务的脑功能区和特点。方法10名右利手健康志愿者进行一项空间记忆广度任务作业的同时进行脑功能磁共振扫描,实验采用组块设计,实验任务与对照任务交替进行,数据采用SPM99软件进行数据分析和脑功能区定位。结果当统计阈值设定为P(0.0001时,被试者的双侧Brodmann区(Brodmann area,BA)6区(额中下回)、右BA9区(额中下回)、左额下回BA47区、双侧顶叶BA7区(楔前叶、顶上小叶)、双侧顶叶BA40区(缘上回),右枕叶BA18、19区、右海马回BA30区、左枕颞交界处BA37区、双侧顶叶中央后回BA3区、左顶叶中央后回BA2区、右中央前回BA4区及左中脑黑质、右小脑均有激活,以顶叶的激活最为显著,其次为额叶、枕叶,其中额叶的BA9区和枕叶的BA18、19区及海马回、小脑的激活有极其明显的右侧半球优势;当统计阈值设定为P(0.001时,脑激活区增加了右前扣带回BA25区,右侧额下回BA47区、左额叶BA9区,左侧枕叶BA17、18、19区及右屏状核,左丘脑侧后核。结论与空间记忆广度有关的主要脑区有BA9、6、7、40、19区和海马回、小脑。它们在进行短时空间记忆任务时所起的作用不同。通过fMRI的研究,揭示了大脑进行空间信息的处理过程。  相似文献   

5.
颞叶癫痫患者磁共振弥散张量成像及记忆损害的研究   总被引:1,自引:0,他引:1  
目的利用磁共振弥散张量成像技术(DTI)研究颞叶癫痫(TLE)患者脑内微观改变及记忆损害的相关脑区。方法对颞叶癫痫患者15例和健康对照者15例,进行DTI检查,利用韦氏记忆量表检测记忆功能。结果 TLE患者部分各向异性弥散(FA)值降低激活区域有颞叶、边缘叶、扣带回和岛叶,升高区有:额叶、顶叶、枕叶,表观系数(ADC)值升高激活区域在颞叶、额叶、枕叶、顶叶;无ADC值降低区域。与健康者相比,颞叶癫痫患者的记忆商数(MQ)(90.73±19.72)显著下降,P<0.01。对照组FA值在左岛叶、颞叶与MQ值正相关;患者组FA值在右额、顶、枕叶、左顶叶与MQ值正相关,在左颞叶与MQ值负相关。对照组ADC与MQ正相关区域在左边缘叶,与MQ成负相关区域在左顶叶、患者组正相关区域在左、右颞叶。结论初步证实TLE患者的脑内结构变化不局限于颞叶,还包括颞叶外网络结构;TLE患者全脑DTI与MQ存在着相关激活脑区,表明记忆功能损害与脑内相关结构改变有关。  相似文献   

6.
联想学习记忆的脑功能磁共振成像   总被引:1,自引:0,他引:1  
目的 通过脑功能磁共振成像(functional magnetic resonance imaging,fMRI)技术检测健康人脑纹状体边缘区(marginal division of the striatum,MrD)是否参与联想学习记忆的过程.方法 对16名右利手健康志愿者进行一项配对词语联想学习记忆任务的同时,进行fMRI扫描.试验采用组块设计并选用SPM 99软件进行数据分析和脑功能区定位.结果 应用单样本t检验(SPM统计软件将体素的激活强度T值在数值上等于t检验的t值),当统计阈值设为P<0.005时,左枕叶和左额上、中回在任务编码时被显著激活(最大激活强度分别为T=13.87、9.36),左纹状体边缘区也在该阶段被明显激活(T=5.46);而左顶叶则在记忆提取阶段被显著激活(T=8.73).结论 除皮质外,皮质下结构如MrD也参与了词语联想学习记忆过程.  相似文献   

7.
目的 探讨急性重性创伤后应激障碍(post traumatic stress disorder,PTSD)患者的脑功能及执行记忆功能时的脑反应.方法 采用功能磁共振成像技术,对经历矿难的10例急性重性PTSD患者(PTSD组)和7例非PTSD对照(非PTSD组)执行症状激发任务,并首次采用1项创伤有关的短期记忆提取任务进行记忆功能的测定.结果 症状激发试验中,PTSD组负性图片相比中性图片,左侧后扣带回、双侧尾状核和右侧丘脑等脑区激活增强,右侧扣带回和双侧额中回激活下降;PTSD组相比非PTSD组,右侧前扣带回、左侧额下回、双侧额中回及双侧颞中回等脑区激活下降,左侧海马旁回激活增高.短期记忆提取任务中,PTSD组负性图片相比中性图片,右侧后扣带回和双侧海马存在明显激活;PTSD组相比非PTSD组,右侧额下回、右侧额中回、左侧枕中回等脑区激活下降.记忆提取任务相比症状激发任务,PTSD组右侧海马旁回激活下降.结论 急性重性PTSD患者在急性期已存在部分脑区激活的下降以及记忆功能的减退.  相似文献   

8.
目的:探讨首发青少年抑郁障碍(MDD)患者静息态脑磁图(rMEG)频谱特点。方法:对15例首发青少年MDD患者(MDD组)及14名正常对照者(对照组)进行rMEG扫描,比较两组频谱分布特点,分析MDD组频谱分布与汉密尔顿抑郁量表(HAMD)评分的关系。结果:①MDD组alpha频段能量左枕叶高于右侧,左颞叶低于右侧;theta频段能量左额、枕叶高于右侧;对照组alpha频段能量左枕叶高于右侧,beta频段能量左枕叶高于右侧,theta频段能量左额、颞及枕叶高于右侧,delta频段能量左颞叶高于右侧,左额叶低于右侧。②与对照组相比,MDD组alpha频段能量右中央区、颞及枕叶明显增高;beta频段能量双侧枕叶明显增高;theta频段能量右颞、枕叶明显增高;delta频段能量右颞、双顶叶明显增高;③MDD组HAMD总分与双侧颞、左顶及双侧枕叶delta频段能量呈正相关;HAMD焦虑因子与右枕叶theta频段能量及左顶、枕叶delta频段能量正相关,与左右顶叶alpha频段能量差呈正相关(P均0.05)。结论:首发青少年MDD患者rMEG的alpha频段能量右侧过度激活,枕叶beta频段能量左侧优势减弱,右枕叶delta频段能量增强且与抑郁程度及焦虑症状相关。  相似文献   

9.
目的:探讨首发抑郁症患者静息态脑磁图频谱分布特征及其与临床症状群的相关性。方法:对18例首发抑郁症患者(患者组)和22名正常对照者(正常对照组)进行静息态脑磁图扫描,采用个体化频谱分析计算方法,比较两组间各脑区δ、θ、α1、α2、α3和β各频段在感兴趣皮质区相对能量值,将有统计学差异的各脑区各频段能量值与抑郁症状严重程度进行相关分析。结果:与正常对照组比较,患者组左枕叶θ频段,右颞叶α1、左枕叶、双侧颞区α2以及双侧枕颞区α3频段能量减弱(P均<0.05);β频段在双侧中央区、顶叶,左侧额叶、枕叶能量显著增强(P<0.05或P<0.01)。相关分析显示,患者组左颞叶、右枕叶α3频谱能量值与汉密尔顿抑郁量表(HAMD-17)阻滞因子分呈负相关(左颞区:r=-0.554,P=0.017;右枕区:r=-0.488,P=0.040)。结论:首发抑郁症患者头后部的快波能量增强,慢波活动减弱;快α频段能量异常或可作为患者阻滞症状评估指标之一。  相似文献   

10.
目的 使用独立成分分析(ICA)法分析功能磁共振(fMRI)数据研究线索诱导因素导致海洛因成瘾者复吸的神经网络. 方法 安徽医科大学附属省立医院神经外科自2010年2月至2010年12月对海洛因成瘾组(n=15,来自安徽省戒毒康复中心)和正常对照组(n=15,来自招募的志愿者)在接受吸毒相关场景视频刺激的同时进行fMRI扫描,然后使用ICA方法对数据进行分析和比较2组受试者脑区的激活情况. 结果 与正常对照组相比,海洛因成瘾组患者双侧前额叶、左前扣带回、双侧后扣带回、左侧顶叶、左侧颞下回的激活降低;双侧伏核、右侧海马以及部分枕叶的激活增强,差异有统计学意义(P<0.05). 结论 ICA方法是一种有效的任务相关fMRI数据分析方法,海洛因成瘾者学习记忆和奖赏系统相关脑区功能改变是线索诱发复吸的重要原因,主要涉及左前额叶、左顶叶、前后扣带回、海马、伏核等脑区.  相似文献   

11.
汉语单字词音、义加工的脑激活模式   总被引:27,自引:0,他引:27  
目的:研究汉字音、义加工的脑机制。方法:采用汉字单字词为实验材料,通过功能磁共振成像扫描执行语音和语义两种认知任务的脑区。结果:语音任务激活的脑区有,左侧顶叶下部和颞上回(BA 40/39/22,BA:Brodmann Area,即布鲁德曼分区,下同),左侧枕中回(BA18/19),右侧枕下回(BA18/19),以及左中央前回(BA6)。语义任务激活的脑区有,左侧顶叶下部(BA40/39)和左侧颞上回(BA22),左侧额下回(BA10/47),右侧额中回和额上回(BA10/11),以及左侧额中回(BA11)。语义任务减去语音任务激活的脑区有,左侧额下回(BA47),左侧海马(BA36)和右侧海马旁回(BA36)。语音任务减去语义任务没有发现任何脑区的显著激活。结论:在语义任务中与语音有关的脑区得到激活;而在语音任务中与语义有关的脑区没有激活。  相似文献   

12.
BACKGROUND: Go, a traditional Chinese chess-like game, requires many unknown functions of the brain including attention, imaging, problem solving and processing of spatial working memory. To date, it remains uncertain whether the intellectual activities required to play Go are related to the frontal lobe. OBJECTIVE: To investigate various patterns of brain region activity while schizophrenic patients and normal subjects engaged in memorizing piece placement in the Chinese game of Go. Spatial working memory was measured in order to validate whether the prefrontal lobe participates in this memory process.
DESIGN, TIME AND SETTING: Non-randomized, concurrent control trial was performed at Second Xiangya Hospital of Central South University, between May and December 2004.
PARTICIPANTS: A total of nine Chinese schizophrenic patients with no brain or bodily diseases and not undergoing electroshock treatment, who were in accordance with the DSM-Ⅳ criteria for schizophrenia, as well as thirteen healthy staffs and students with matched age, sex, and education were included. Patients and control subjects had no neurological disorders or mental retardation. In addition, all participants were right-handed. METHODS: The cognitive task for functional magnetic resonance imaging was a block design experiment. Both groups were asked to remember the placement of pieces in the Chinese game of Go on a computer screen. A brain activation map was analyzed in SPM99.
MAIN OUTCOME MEASURES: Brain responses were compared with regard to activation region size, volume, and asymmetry indices. RESULTS: Compared with the control group, the reaction time was significantly delayed in schizophrenics performing the working memory task (P 〈 0.05). When performing the tasks, normal subjects showed significant activation of the bilateral dorsolateral prefrontal lobe with left dominance; the asymmetry indices were: frontal lobe, +0.32; temporal lobe, 0.58; parietal lobe, 0.41 ; and occipital lobe, 0.34. On the other hand, schizophrenics showed right dominance and had a broader activation region of the prefrontal lobe (asymmetry indices: frontal lobe, 0.10; temporal lobe, +0.38; parietal lobe, +0.24; and occipital lobe, 0.00). When comparing the normal group subtracted with the schizophrenic group, no significant lateralization was found in the frontal lobes but significant activation was found in the left anterior central gyrus, left middle frontal gyrus and in both sides of the cingulate gyrus. Comparing the schizophrenic group subtracted with the normal group, there was significant right lateralization of the frontal lobe and abnormally activated regions on both sides of the anterior central gyrus, middle frontal gyrus, left inferior frontal gyrus, right medial frontal gyrus and the right insular lobe. CONCLUSION: Different brain activation regions are involved in memorizing the placement of pieces in Chinese Go between schizophrenia and healthy subjects. Schizophrenics showed right dominance and border activation range, indicating that the prefrontal cortex plays an important role in memory information processing and resource allocation when remembering piece placement in the game of Go.  相似文献   

13.
目的 基于静息态脑电图探索卒中后抑郁(post-stroke depression,PSD)脑网络特征异常改变,提取 客观生物标志物。 方法 回顾性分析深圳市人民医院脑电数据库中缺血性卒中慢性期患者病例资料,收集静息态 脑电图与汉密尔顿抑郁量表(Hamilton depression scale,HAMD)、MMSE及NIHSS评分资料。以HAMD评分 ≥20分为分界值,并通过病灶位置及体积匹配将患者分为PSD组和卒中后非抑郁(post stroke nondepression, PSND)组。脑电图数据预处理后,分别基于相干性虚部及能量包络在皮层源层面建立不同 频段功能连接矩阵,采用基于网络的统计方法分析两组间差异。 结果 与PSND组比较,PSD组患者①基于相干性虚部的脑网络连接在δ频段减弱,以顶叶脑区连接 减弱更明显;θ频段减弱,以左侧额顶颞枕、边缘叶及右侧额叶连接减弱更明显;γ频段增强,以左 侧额叶、边缘叶及右侧顶叶脑区连接增强更明显;②基于能量包络的脑网络连接在α频段增强,以双 侧顶枕叶脑区连接增强更明显。 结论 PSD患者脑网络发生异常改变,静息态脑电图是揭示这种改变的有效工具。  相似文献   

14.
Diffusion tensor imaging (DTI) studies of schizophrenia have revealed white matter abnormalities in several areas of the brain. The functional impact on either psychopathology or cognition remains, however, poorly understood. Here we analysed both functional MRI (during a working memory task) and DTI data sets in 18 patients with schizophrenia and 18 controls. Firstly, DTI analyses revealed reductions of fractional anisotropy (FA) in the right medial temporal lobe adjacent to the right parahippocampal gyrus, likely to contain fibres of the inferior cingulum bundle, and in the right frontal lobe. Secondly, functional MRI revealed prefrontal, superior parietal and occipital relative hypoactivation in patients with the main effect of task. This was accounted for by reduced prefrontal activation during the encoding phase of the task, but not during maintenance or retrieval phases. Thirdly, we found a direct correlation in patients between the frontal FA reduction (but not medial temporal reductions) and fMRI activation in regions in the prefrontal and occipital cortex. Our study combining fMRI and DTI thus demonstrates altered structure-function relationships in schizophrenia. It highlights a potential relationship between anatomical changes in a frontal-temporal anatomical circuit and functional alterations in the prefrontal cortex.  相似文献   

15.
Cao F  Peng D  Liu L  Jin Z  Fan N  Deng Y  Booth JR 《Human brain mapping》2009,30(3):797-809
Developmental differences in the neurocognitive networks for phonological and semantic processing in Chinese word reading were examined in 13 adults and 13 children using functional magnetic resonance imaging (fMRI). Rhyming and semantic association judgments were made to two-character words that were presented sequentially in the visual modality. These lexical tasks were compared with a nonlinguistic control task involving judgment of line patterns. The first main finding was that adults showed greater activation than children in right middle occipital gyrus on both the meaning and rhyming task, suggesting adults more effectively engage right hemisphere brain regions involved in the visual-spatial analysis of Chinese characters. The second main finding was that adults showed greater activation than children in left inferior parietal lobule for the rhyming as compared with the meaning task, suggesting greater specialization of phonological processing in adults. The third main finding was that children who had better performance in the rhyming task on characters with conflicting orthographic and phonological information relative to characters with nonconflicting information showed greater activation in left middle frontal gyrus, suggesting greater engagement of brain regions involved in the integration of orthography and phonology.  相似文献   

16.
Zheng J  Qin B  Dang C  Ye W  Chen Z  Yu L 《Epilepsy research》2012,100(1-2):67-73
Patients with temporal lobe epilepsy (TLE) often suffer from cognitive deficits. However, it remains elusive whether the performance of TLE patients in the attentional networks test (ANT) is impaired. Functional magnetic resonance imaging (fMRI) can accurately reflect the hemodynamics and functional activities in certain regions of the brain. In the current study, we aimed to investigate the characteristics and neural mechanisms of the functions of the alertness network in patients with TLE using the ANT and fMRI. A total of 12 patients with TLE and 8 healthy controls underwent the ANT behavioral tests and subsequent block-design fMRI scanning. The results showed that the response times of the alertness network had no significant difference between the TLE group and the healthy control group. The fMRI data showed that the activation of the cerebellum, right occipital lobe, right frontal and brainstem was significantly weaker in TLE patients than in healthy control. Our data indicate that despite neuropsychological test performance is normal; the alerting network is deficient in the TLE patients. The decreased activation of brain regions of right occipital lobe, cerebellum, right frontal lobe, brain stem and temporal lobe may be the neural basis of altering network impairment in TEL patients.  相似文献   

17.
Gaab N  Schlaug G 《Neuroreport》2003,14(18):2291-2295
We compared brain activation patterns between musicians and non-musicians (matched in performance score) while they performed a pitch memory task (using a sparse temporal sampling fMRI method). Both groups showed bilateral activation of the superior temporal, supramarginal, posterior middle and inferior frontal gyrus, and superior parietal lobe. Musicians showed more right temporal and supramarginal gyrus activation while non-musicians had more right primary and left secondary auditory cortex activation. Since both groups' performance were matched, these results probably indicate processing differences between groups that are possibly related to musical training. Non-musicians rely more on brain regions important for pitch discrimination while musicians prefer to use brain regions specialized in short-term memory and recall to perform well in this pitch memory task.  相似文献   

18.
Liu Y  Dunlap S  Fiez J  Perfetti C 《Human brain mapping》2007,28(11):1223-1234
Native English speakers with no knowledge of Chinese were trained on 60 Chinese characters according to one of three mapping conditions: orthography to pronunciation and meaning (P + M), orthography to pronunciation (P), and orthography to meaning (M). Following the training, fMRI scans taken during passive viewing of Chinese characters showed activation in brain regions that partially overlap the regions found in studies of skilled Chinese readers, but typically not found in alphabetic readers. Areas include bilateral middle frontal (BA 9), right occipital (BA 18/19), and fusiform (BA 37) regions. The activation pattern of Chinese characters was similar across the three groups. However, peak location was different in the left middle frontal region between groups. Direct contrasts between the groups also revealed stronger activation of left middle frontal in the P + M group. The results suggest that learners acquired skill in reading Chinese characters using a brain network similar to that used by Chinese native speakers. The results are consistent with the system accommodation hypothesis: The brain's reading network accommodates to features of an acquired writing system.  相似文献   

19.
目的 探索脑小血管病(cerebral small vessel disease,CSVD)总负荷与记忆力下降老年患者认知功能、
脑萎缩及脑灌注的关系。
方法 回顾性纳入2015年12月-2017年12月同济医院神经内科门诊及记忆减退专病门诊主诉记忆力
下降患者,收集一般资料及影像学信息,进行认知评估、CSVD总负荷评分、全脑及各脑叶脑萎缩评分,
计算脑血流(cerebral blood flow,CBF)值。采用Spearman相关分析CSVD总负荷评分与认知功能、脑萎
缩及CBF的关系。
结果 共纳入200例,平均年龄69.16±9.44岁,男性99例(49.5%)。CSVD总负荷与MoCA评分呈负相
关(r =-0.202,P =0.004);与全脑(r =-0.234,P =0.001)、额叶(r =-0.252,P <0.001)、顶叶(r =-
0.253,P <0.001)、枕叶(r =-0.224,P =0.001)CBF呈负相关;CSVD负荷与全脑(r =0.313,P <0.001)、
额叶(r =0.393,P<0.001)及顶叶(r =0.237,P =0.001)的脑萎缩评分呈正相关。
结论 CSVD总负荷越高,认知功能越差、脑灌注越低、脑萎缩越严重。  相似文献   

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