联想学习记忆的脑功能磁共振成像

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.     

空间记忆广度的脑功能磁共振研究

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。     

慢性失眠患者汉字工作记忆的功能磁共振研究

目的探讨慢性失眠患者汉字任务下脑激活区改变。方法对40例慢性失眠患者和50例正常对照组进行汉字工作记忆功能磁共振扫描。结果慢性失眠组与正常组脑激活区存在差异:慢性失眠组编码期枕叶、右前额和右边缘叶激活增强;保持期左前额激活下降;提取期激活增强区为右枕叶,激活下降区为左尾状核和右侧丘脑。结论慢性失眠患者在文字记忆任务编码期及提取期均出现了右脑皮层的代偿激活,保持期出现了左前额激活下降,提取期出现了皮层下区域激活的下降,提示慢性失眠在文字记忆处理过程出现了相关脑区的损害和异常激活。     

血管性认知功能损害患者工作记忆和计算能力的fMRI研究

目的研究血管性认知功能损害(vascular cognitive impairment,VCI)患者在执行工作记忆和计算任务时,其功能磁共振(functional magnetic resonance imaging,fMRI)的信号激活脑区强度同正常人进行比较是否存在区别,明确VCI患者脑功能区信号变化特点,为VCI提供影像学诊断依据。方法采用简明精神状态检查(mini-mental state examination,MMSE)进行智能评定。利用功能磁共振成像技术,对25例VCI患者和15例对照组患者进行倒背数字作业,计算能力测验,对脑激活功能区进行分析,利用SPM2软件对图像数据进行处理。结果 VCI患者倒背数字作业时,双侧额中回、海马及颞上回激活脑区像素值显著减少(P<0.05);在计算能力测试方面,双侧额中回、海马、颞上回以及左侧角回、缘上回激活脑区像素值也显著减少(P<0.05)。结论在执行工作记忆和计算任务时,VCI患者存在特定激活脑区信号的减弱,通过对fMRI信号的侦测,可以为VCI的早期诊断提供影像学依据。     

颞叶癫痫患者磁共振弥散张量成像及记忆损害的研究

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。     

正常人词语流畅性作业的脑功能磁共振成像研究

目的 利用功能磁共振成像(fMRI)技术探讨词语流畅性作业的脑功能定位。方法对18名健康志愿者进行词语流畅性作业的fMRI检查,fMRI用梯度回波-平面回波成像序列采集数据,经工作站处理后获功能图像。结果 经Fisher精确检验法,健康志愿者的双侧额上回、双侧额中回、右侧额下回及右侧扣带回的激活脑区计数,与理想激活脑区计数的差异均无显著性(P>0.05),其余脑区激活计数的差异均有显著性(P<0.05)。结论 双侧额叶背外侧及右侧额叶腹外侧可能参与长时记忆的提取过程,其中额叶背外侧可能参与核查及管理工作,而额叶腹外侧可能参与搜寻特异目标的过程。     

fMRI及DTI技术在成人工作记忆研究的初步探索

目的：联合应用脑功能磁共振成像（BOLD—fMRI）和弥散张量成像（DTI）两种磁共振技术,探索工作记忆功能激活部位与叶间白质纤维束的关系。方法：健康志愿者16名,以步进式视觉累加试验作为刺激模式,扫描获得fMRI激活图及各向异性（FA）图。将两者叠加,选取双侧额顶叶白质兴趣区测量其部分FA值。结果：①额顶叶皮质为工作记忆功能最主要的激活区;②脑的激活像素几乎均位于FA程度低的区域（P〈0．01）;③左额顶间白质FA值较对侧高（P〈0．02）。结论：联合应用fMRI和DTI技术提示成人工作记忆功能与额顶叶白质纤维髓鞘化程度密切相关。     

维吾尔语语义加工脑功能定位的磁共振成像研究

目的 利用功能磁共振(fMRI)技术研究维吾尔族对其母语(维吾尔文字)进行词义联想脑功能的激活区及语言的偏侧化.方法 29例健康志愿者作为受试对象,通过视觉刺激对每个单音节实词进行词义联想同时行fMRI,所有数据经神经功能分析软件对相关脑皮质激活区进行个体分析及组分析.结果 多个皮质出现激活区,主要出现在双侧额中回、额下回、枕中回、中央前回及梭状回,左侧颞中回、顶上下小叶、楔前叶,右侧颞上回、舌回.左侧大脑半球激活体积明显大于右侧.结论 多个脑功能区参与维吾尔语义加工,fMRI能够很好地发现这些功能区,维吾尔族语言优势半球为左侧大脑半球.     

慢性失眠患者数字工作记忆的功能磁共振研究

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.     

颞叶癫痫患者警觉功能的脑功能磁共振研究

目的利用注意网络测试(ANT)软件和功能核磁共振(fMRI)成像技术探讨颞叶癫痫(TLE)患者的警觉网络功能特点、激活模式及其脑功能状态。方法对12例TLE患者及匹配的8名健康志愿者进行研究。使用ANT软件进行警觉功能行为学测试,记录反应时间(RT);并采用ANT改良的警觉网络功能组块模式fMRI扫描,fMRI数据采用统计参数图(SPM2)软件分析。结果 TLE患者组与健康对照组ANT警觉网络功能的反应时间无差异。健康对照组警觉网络fMRI显示右枕叶、小脑明显激活;右边缘叶、右额叶及左侧颞叶、脑干部分激活。TLE患者组存在相同警觉网络相关脑区,但激活明显减弱且颞叶和脑干无激活。结论健康对照警觉网络功能与右侧枕叶、小脑、右额叶、脑干及颞叶等脑区相关。TLE患者存在警觉网络相关脑区功能明显低下,可能是TLE患者出现警觉功能损害的脑功能基础。     

Presurgical functional mapping with functional MRI

PURPOSE OF REVIEW: The present article describes current indications for functional MRI in the preoperative planning of neurosurgical patients. Functional MRI continues to have an expanding role. RECENT FINDINGS: There are three main categories of patients who commonly undergo preoperative functional MRI. Patients with lesions close to eloquent cortex can benefit from preoperative functional MRI to assess resectability and reduce the possibility of functional deficit. The second group are those patients who have functional MRI as part of their preoperative planning to localize language dominance and for functional localization of memory. The final group are those patients in whom attempts are made to image and localize abnormal brain function. This has a specific application in the field of epilepsy surgery (electroencephalographic-correlated functional MRI). These three roles require different spatial resolutions. Advances in multimodality imaging are enabling more accurate localization of function intraoperatively. SUMMARY: It is hoped that the increasing use of functional MRI in combination with both preoperative and intraoperative imaging modalities may reduce the risk of neurological deficit while improving completeness of resection. Electroencephalographic-correlated functional MRI may provide an additional method for localization of epileptogenic foci.     

Anatomical and functional distribution of functional MRI language mapping

ObjectiveThe aim of the present study was to compare localization of the language cortex using electrical cortical stimulation (ECS) and functional magnetic resonance imaging (fMRI) to establish the relevance of fMRI language mapping.MethodsLanguage mapping with fMRI and functional ECS mapping were retrospectively compared in ten patients with refractory epilepsy who underwent fMRI language mapping and functional ECS mapping between June 2012 and April 2019. A shiritori task, a popular Japanese word chain game, was used for fMRI language mapping.ResultsBOLD signal activation was observed in the left inferior frontal gyrus (including the pars opecularis and the pars triangularis), and superior temporal gyrus, which is a language-related area, as well as in the left superior and middle frontal gyri, the intraparietal sulcus, and fusiform gyrus. These results were compared with ECS to elucidate the functional role of the activated areas during fMRI language tasks. These activated areas included language areas, negative motor areas, supplementary motor areas (SMAs), and non-functional areas.ConclusionThe activated areas of fMRI language mapping include language-related areas, the negative motor area, and SMAs. These findings suggest the involvement of language and higher order motor networks in verbal expression.     

Predictors of change in functional competence and functional behavior after functional adaptation skills training for schizophrenia

ABSTRACT: Functional recovery is an important treatment target in schizophrenia. Although medication is effective at reducing positive symptoms of the disorder, these improvements do not translate to improved functioning. In this study, schizophrenia outpatients (N = 54) received the psychosocial treatment Functional Adaptation Skills Training. Hierarchical regression analyses determined whether baseline neurocognitive, symptom, course of illness, and demographic variables predicted improvement in performance-based measures of functional competence and case manager-rated real-world behavior after the intervention. Consistent with previous research, neurocognition emerged as a predictor of improved competence and behavior. Symptoms played a minor role in predicting change; however, institutionalization history seemed to be an important rate limiter for functional recovery. Correlations among change scores were modest, with evidence for concomitant changes in competence and performance. The predictors of change after psychosocial treatment vary by the domain (e.g., adaptive and interpersonal) of functioning and the level of assessment (e.g., competence and performance).     

Transsylvian functional hemispherectomy

Objective To describe the technique of transsylvian–transventricular functional hemispherectomy developed at our institution.Methods We review appropriate patient selection and evaluation, timing of surgery, selection of surgical approach, preoperative preparation, details of operative procedure, and postoperative management.Conclusions The transsylvian “keyhole” functional hemispherectomy technique involves a smaller craniotomy than other functional hemispherectomy techniques and consists of transsylvian exposure, resection of mesial temporal structures, transventricular frontobasal disconnection, callosotomy, and occipitoparietal disconnection. The key advantages of this approach compared to the Rasmussen’s “classic” functional hemispherectomy are smaller exposure, shorter operative time, and lower blood loss. The efficacy of functional hemispherectomy procedures in achieving seizure freedom appears to be at least as good compared to resective procedures. The long-term complication rate will require longer follow-up times.     

论"功能神经外科学"

神经外科学从治疗的疾病谱上主要划分为脑肿瘤、脑血管病、脑外伤和功能脑病。采用手术的方法修正神经系统功能异常的医学分支是为功能神经外科学(Functional Neurosurgery),早期亦称生理神经外科学(Physiologic Neurosurgery),或应用神经生理学     

Residual functional connectivity in the split-brain revealed with resting-state functional MRI

Split-brain patients present a unique opportunity to address controversies regarding subcortical contributions to interhemispheric coordination. We characterized residual functional connectivity in a complete commissurotomy patient by examining patterns of low-frequency BOLD functional MRI signal. Using independent components analysis and region-of-interest-based functional connectivity analyses, we demonstrate bilateral resting state networks in a patient lacking all major cerebral commissures. Compared with a control group, the patient's interhemispheric correlation scores fell within the normal range for two out of three regions examined. Thus, we provide evidence for bilateral resting state networks in a patient with complete commissurotomy. Such continued interhemispheric interaction suggests that, at least in part, cortical networks in the brain can be coordinated by subcortical mechanisms.     

Widespread functional disconnectivity in schizophrenia with resting-state functional magnetic resonance imaging

Using resting-state functional magnetic resonance imaging, we examined the functional connectivity throughout the entire brain in schizophrenia. The abnormalities in functional connectivity were identified by comparing the correlation coefficients of each pair of 116 brain regions between 15 patients and 15 controls. Then, the global distribution of the abnormal functional connectivities was examined. Experimental results indicated, in general, a decreased functional connectivity in schizophrenia during rest, and such abnormalities were widely distributed throughout the entire brain rather than restricted to a few specific brain regions. The results provide a quantitative support for the hypothesis that schizophrenia may arise from the disrupted functional integration of widespread brain areas.