基于组独立成分分析方法的情绪刺激对脑部激活区域的研究

目的观察积极和消极情绪状态下的脑激活差异情况,探究脑部对正性和负性情绪信息的处理机制。方法采用组独立成分分析技术处理情绪刺激下的功能磁共振图像数据。结果在积极情绪刺激下,杏仁核周围、顶叶和右扣带回区域的连接性十分显著;而在消极的情绪刺激下,杏仁核和丘脑附近区域激活程度明显,并且这些区域与楔叶右侧、左侧颞中回区域产生高度相关性。结论大脑处理消极情绪时,激活脑区与皮层-丘脑枕核-杏仁核通路大致相符,并且左侧楔前叶和右侧后扣带回区域的连接性存在显著下降。     

动态表情情绪识别相关脑区的fMRI研究

目的:利用事件相关的功能核磁共振成像技术研究健康汉族女性对动态表情的识别情况并探讨其神经基础。方法:利用1.5T功能核磁共振成像系统检测13名女性健康受试者识别悲伤、喜悦及中性动态表情视频时的脑部反应。图像数据经SPM2软件处理和统计分析,获得脑区激活图。结果:与识别十字架相比,识别中性表情激活左额中回、双侧中央前回、右侧杏仁核、左顶下小叶、右中央后回以及丘脑等。与识别中性表情相比,识别喜悦表情激活右额内侧回、右额上回、右额中回、右前扣带回、左胼胝体下回、右枕上回、右枕下回、左枕中回及右颞上回等脑区,而识别悲伤表情激活左额内侧回、右额中回、左颞下回以及左颞上回等脑区。结论:面孔加工及动态表情的识别由脑内一个分布式神经网络所调控,其中额内侧回参与多种情绪的加工,可能是情绪加工的共同通路,而颞上回主要负责面部动态特征的加工。     

音乐刺激激活人脑情感系统的fMRI研究

目的：利用fMRI技术，对音乐欣赏相关脑功能区进行定位，并初步探讨音乐情感反应和音乐治疗的可能神经机制。方法：采用组块设计模式，对30名非音乐专业志愿者进行被动聆听音阶、轻音乐和恐怖音乐（各3段）实验。应用SPM99软件对实验结果进行组分析，获得平均激活图。结果：轻音乐和恐怖音乐可激活大脑与情感加工相关的脑区．前者主要包括双侧前额皮层外侧部（左侧为著）、左侧眶额皮层、扣带回前部、左侧岛叶前部、右侧丘脑和左侧豆状核；后者主要包括双侧前额皮层外侧部（右侧为著）、双侧眶额皮层、双侧额内回和扣带回前部和双侧杏仁复合体，结论：音乐可有效激活人脑与情感加工相关脑区；大脑对喜悦和恐惧情感具有不同（或部分交叉）的神经加工网络．其中．轻音乐引起的正性情感加工可能是音乐治疗的部分神经基础。     

基于组独立成分分析的情绪刺激功能磁共振成像研究

目的通过独立成分分析(ICA)方法研究大脑对正、负性情绪的响应机制。方法用组独立成分分析方法、聚类及可视化的可靠性评估方法来评估和选择相应的独立成分研究响应机制。结果算法处理后的成分数据对积极和消极情绪的刺激形成特定处理通路。结论积极情绪下的高级脑区呈现活跃状态,且左侧额中回与海马旁回通路的联结性明显上升;消极情绪刺激的激活通路:皮层-丘脑枕核-杏仁核,且右扣带回区域与左侧楔前叶间的联结性下降明显。     

情感语言语境联想刺激模式的fMRI研究

目的：建立功能核磁共振成像（functional Magnetic Resonance Image，fMRI）的语言情感刺激模式，探讨阅读联想具有正性情感（Positive Emotion）及负性情感（Negative Emotion）的语言时，大脑激活区域的差异。方法：健康志愿者6名，均为在校研究生．以汉语为母语，平而回波序列（Echo Planar Imaging，EPI），血氧水平依赖法（Blood Oxygenation Level—dependent MRI，BOLD）组块设计（Block Design）获取功能成像。嘱受试者注视具有正性或负性情感的二字中文词汇，理解其语义后进行联想。结果：受试者理解率和合作率为100％。受试者报告可以区分出两组任务代表不同的情感。一组产生兴奋、高兴的情绪，甚至想笑；而另一组产生悲伤、难过、不安的情绪。负性语育任务激活的区域较正性语言任务激活的区域广泛。负性任务趋向于双侧激活，主要激活了双侧额上回，额中回，中央前回，顶上小叶，颞上回，颞中回；正性语肓任务主要激活了左侧额上回，中央前回，顶上小叶，颞上回，颞下回及小脑。负性语言任务还见到扣带前回、杏仁体、丘脑、尾状核头及胼胝体的激活。正性语言任务及负性语青任务可见到枕叶的双侧激活。结论：情感的处理具有偏侧性。负性情感更易被诱发，并伴随更多的脑区被激活。枕叶可能参与情感处理。     

视觉情绪刺激诱导的神经磁场研究

目的 使用脑磁图探讨健康右利手受试者给予视觉情绪图片刺激早期情绪相关脑区磁场激活特征.方法 12例健康右利手受试者,给予国际情绪图片库(IAPS)正性、中性、负性情绪图片刺激同时记录脑磁图信号,使用SPM8b软件进行数据分析,两样本t检验,设P＜0.02,K＞10体素阈值的脑区激活有意义.结果 正常人在给予正性情绪图片刺激时与给予中性情绪图片刺激时比较发现右侧的岛叶激活增强(0～100ms,t=2.87,P=0.004;100～200ms,t=2.97,P=0.004;200～300ms,t=2.67,P=0.008;300～400ms,t=2.65,P=0.007);给予负性情绪图片刺激时与给予中性情绪图片时比较发现右侧的额下回激活增强(0～100ms,t=2.27,P=0.016;100～200ms t=2.28,P=0.016;200～300ms,t=2.30,P=0.015;300～400ms,t=2.29,P=0.016);给予正性情绪图片与负性情绪图片刺激时比较未发现激活有差异的脑区.结论 正常人右侧岛叶、右侧额下回脑区在情绪唤醒度评价、趋向及回避行为评价中起作用.     

同一经络上穴位的脑功能磁共振成像研究

目的:手针针刺同一经络上但被同一神经阶段支配的不同穴位的核磁共振功能成像研究。方法:对33名志愿者进行手针针刺,每一位志愿者会随机地接受一个点的针刺:太冲穴,中都穴,太冲穴旁的非穴位点和中都穴旁的非穴位点,在针刺同时用1.5T核磁共振扫描仪进行扫描,得到针刺穴位相对于非穴位的激活脑区。结果:相对于刺激假穴组,刺激真穴组都激活了额内侧面、前扣带回(ACC,BA24/32/25);对侧中央后回、顶叶BA7/31、额中回;还有同侧的BA19和小脑。针刺太冲穴特异地激活了两侧额中回和颞下回,对侧颞中回、岛叶、小脑和同侧额中回、尾状核;针刺中都穴特异地激活了对侧颞上回、顶下小叶、同侧的中央前回和额上回。结论:针刺同一经络上的不同穴位会引起相似的大脑反应,而针刺同一经络上不同穴位所引起的特异性激活也表明了穴位特异性的存在。     

不同部位重复经颅磁刺激治疗原发性失眠的疗效对比

目的：对比研究不同部位重复经颅磁刺激（rTMS）治疗原发性失眠的疗效。方法：选择150例原发性失眠患者,rTMS治疗部位随机分为左前颐背外侧组、右前额背外侧组、左中颞组、前额组、对照组,每组30例,在患者和治疗师双盲的前提下,每次连续刺激22rain,每日1次,疗程10d。分别观察5组患者在治疗前和治疗结束后第2天的临床疗效、用匹兹堡睡眠质量评分（PSQI）。结果：磁疗中,部分患者有瞌睡或浅睡感,左前额背外侧组和右前颁背外侧组尤为显著。治疗结束后第2天,左前额背外侧组的有效率为77％,右前额背外侧组的有效率为73％,左中顾组的有效率为47％,前颐组的有效率为43％,左前额背外侧组和右前额背外侧组的有效率高于左中颞组和前额组,前两者与后两者分别两两检验差异有统计学意义（P〈0．05）;左、右前额背外侧组之间无明显差异（P〉0．05）,左中顾和前顿组之间也无明显差异（P〉0．05）。结论：rTMS治疗部位左、右前额背外侧区治疗原发性失眠疗效显著,优于其他区域。     

男性重性抑郁症患者识别动态面部表情情绪偏向性的fMRI研究

目的:抑郁症患者存在负性认知模式,本研究旨在探讨男性抑郁症患者识别动态面部表情情绪偏向性的神经基础.方法:利用1.5T功能核磁共振成像系统检测12名男性抑郁症患者及相匹配的12名健康男性识别悲伤、喜悦及中性面部表情视频时的脑部反应.功能:MRI原始图像数据经转化格式,SPM2软件处理,配对t检验统计分析.结果:与正常对照相比,抑郁症患者明确识别喜悦情感(识别喜悦表情-识别中性表情)时活动增加的脑区有右枕中回(BA37)、左额中回(BA6)、左顶下小叶(BA40)、左中央前回(BA6)、左中央后回(BA2),而活动降低的脑区有左颞上回(BA38)、左颞中回(BA21)、右额下回(BA10).明确识别悲伤情感(识别悲伤表情-识别中性表情)时活动增加的脑区包括右额中回(BA6)、左扣带回(BA31),右梭状回(BA20)、右中央后回(BA2).但正常对照较抑郁症患者在悲伤情绪的识别中未发现显著激活增强的脑区.结论:抑郁症患者明确识别动态面部表情的神经基础与正常对照存在差异,表现为需要更多脑区参与情绪刺激的识别,尤其在悲伤情绪识别中,情绪相关脑区活动增加明显.     

功能磁共振在大脑皮质发育障碍患者的初步应用研究

目的：应用功能磁共振（fMRI）探讨6名正常受试者及2例皮质发育障碍（DCDs）患者在进行汉语词汇加工过程中脑激活模式，探讨DCDs患者与正常受试者之间脑激活区域的差异与临床意义。方法：本实验采用听觉刺激，以汉语单词理解为语言作业任务。结果：①正常受试者均出现显著的脑区激活，传统语言脑区Wemicke和Broca区激活在双侧大脑半球基本是对称的。除传统语言脑区激活外，还出现其它脑区激活现象。②两例DCDs患者表现为基本语言功能区的激活，诸如Wemicke区和Broca区激活。但脑激活表现为显著的不对称性，甚至完全偏侧性。结论：fMRI能够对大脑DCDs患者功能重塑皮质进行定位，为DCDs伴难治性癫痫患者手术治疗，避免损伤重要功能区提供了有益的保障。     

Comparable fMRI activity with differential behavioural performance on mental rotation and overt verbal fluency tasks in healthy men and women

To explicate the neural correlates of sex differences in visuospatial and verbal fluency tasks, we examined behavioural performance and blood-oxygenation-level-dependent (BOLD) regional brain activity, using functional magnetic resonance imaging, during a three-dimensional (3D) mental rotation task and a compressed sequence overt verbal fluency task in a group of healthy men (n=9) and women (n=10; tested during the low-oestrogen phase of the menstrual cycle). Men outperformed women on the mental rotation task, and women outperformed men on the verbal fluency task. For the mental rotation task, men and women activated areas in the right superior parietal lobe and the bilateral middle occipital gyrus in association with the rotation condition. In addition, men activated the left middle temporal gyrus and the right angular gyrus. For verbal fluency, men activated areas in the bilateral superior frontal gyrus, right cingulate gyrus, left precentral gyrus, left medial frontal gyrus, left inferior frontal gyrus, thalamus, left parahippocampal gyrus and bilateral lingual gyrus, and women activated areas in the bilateral inferior frontal gyrus and left caudate. Despite observing task related activation in the hypothesised areas in men and women, no areas significantly differentiated the two sexes. Our results demonstrate comparable brain activation in men and women in association with mental rotation and verbal fluency function with differential performance, and provide support for sex differences in brain–behaviour relationships.     

The effect of transient increase in oxygen level on brain activation and verbal performance.

This study aimed to investigate the hypothesis that a transient increase in oxygen level administered to subjects increases the BOLD effect in brain regions associated with verbal cognitive functioning and enhances performance accuracy. A verbal task was presented while brain images were scanned by a 3T fMRI system. The accuracy rate on the verbal task was enhanced during 30% oxygen administration compared to 21% oxygen administration. The neural activations were observed at the occipital, parietal, temporal and frontal lobes, during both 21% and 30% oxygen administration. Increased brain activations were observed in the right middle frontal gyrus, right inferior frontal gyrus, right superior frontal gyrus, cingulate gyrus, left middle temporal gyrus, and left fusiform gyrus with 30% oxygen administration. These results suggest that a higher concentration of breathed oxygen increases saturation of blood oxygen in the brain, and facilitates verbal cognitive performance.     

Thalamocortical circuits: fMRI assessment of the pulvinar and medial dorsal nucleus in normal volunteers

This fMRI study investigates the activation of the thalamic nuclei in a spatial focusing-of-attention task previously shown to activate the pulvinar with FDG-PET and assesses the connectivity of the thalamic nuclei with cortical areas. Normal right-handed subjects (eight men, eight women, average age=32 years) viewed four types of stimuli positioned to the right or left of the central fixation point (left hemifield-large letter, left hemifield-small letter display with flanking letters; right hemifield-large letter, right hemifield-small letter display with flankers). BOLD responses to small letters surrounded by flankers were compared with responses to large isolated letters. To examine maximum functional regional connectivity, we modeled "subject" as a random effect and attained fixed effect parameter estimates and t-statistics for functional connectivity between each of the thalamic nuclei (pulvinar, medial dorsal, and anterior) as the seed region and each non-seed voxel. Greater BOLD activation for letters surrounded by flankers than for large letters was observed in the pulvinar as anticipated and was also marked in the medial dorsal nucleus (MDN), anterior and superior cingulate (BA24 and BA24'), dorsolateral prefrontal cortex, and frontal operculum and insula. For the MDN, maximal functional connectivity was with the dorsolateral prefrontal cortex; correlations with left superior temporal, parietal, posterior frontal, and occipital regions were also observed. For the pulvinar, maximal functional connectivity was with parietal BA39; for anterior thalamus, with anterior cingulate.     

Brain activation during encoding and recognition of verbal and figural information in older adults

Positron emission tomography (PET) patterns of cerebral blood flow associated with verbal and figural memory are described in relation to their value as functional probes for studying longitudinal changes that occur in the aging brain. Relative to a matching control task, verbal and figural encoding increase blood flow in prefrontal cortex (PFC), anterior cingulate, insular, lateral and medial temporal, occipital cortex and the cerebellum. Additionally, medial temporal regions exhibited greater activity during figural encoding relative to verbal encoding. During recognition, blood flow increases in prefrontal, cingulate, insular, and lateral temporal and Broca's areas. Analysis of hemispheric asymmetry reveals that the prefrontal cortex exhibits regionally dependent results. Prefrontal region BA 10 demonstrates more bilateral activation during encoding and retrieval, whereas BA 46 shows right greater than left activation during both encoding and retrieval. Overall, the two tasks activate diverse regions within the frontal, temporal and occipital lobes of the brain, including areas that show age-related structural changes, proving their usefulness in the longitudinal assessment of brain function in the elderly.     

Dysfunction of a distributed neural circuitry in schizophrenia patients during a working-memory performance

BACKGROUND: In a recent longitudinal study of first-episode schizophrenia patients, we found that while dysfunction of the right dorsolateral prefrontal cortex (DLPFC), right thalamus, left cerebellum and cingulate gyrus normalized with antipsychotic treatment and significant reduction in symptomatology, the left DLPFC, left thalamus, and right cerebellum remained disturbed. In the present study we investigated whether these abnormalities are also present in clinically stable, relatively well-functioning schizophrenia patients in comparison to control subjects during performance of the N-back working-memory task. METHOD: Twelve schizophrenia and 12 control subjects completed the study. The functional images collected during scanning were analyzed using a random-effects model in a restricted set of six regions of interest (ROIs). In addition, the exploratory search in the entire brain volume was performed. RESULTS: The ROI analyses revealed relative underactivation in the region of the left DLPFC and the right cerebellum, as well as overactivation in the left cerebellum. The exploratory whole-brain search exposed additional overactivation in the medial frontal, anterior cingulate, and left parietal cortices. CONCLUSIONS: The present study provides evidence of significant underactivations in stable schizophrenia patients in regions that we have previously observed to be dysfunctional in acutely psychotic and partially remitted patients, together with extensive overactivations in several regions that potentially reflect some compensatory mechanism or increased effort on the working-memory task.     

Navigation ability dependent neural activation in the human brain: an fMRI study

Visual-spatial navigation in familiar and unfamiliar environments is an essential requirement of daily life. Animal studies indicated the importance of the hippocampus for navigation. Neuroimaging studies demonstrated gender difference or strategies dependent difference of neural substrates for navigation. Using functional magnetic resonance imaging, we measured brain activity related to navigation in four groups of normal volunteers: good navigators (males and females) and poor navigators (males and females). In a whole group analysis, task related activity was noted in the hippocampus, parahippocampal gyrus, posterior cingulate cortex, precuneus, parietal association areas, and the visual association areas. In group comparisons, good navigators showed a stronger activation in the medial temporal area and precuneus than poor navigators. There was neither sex effect nor interaction effect between sex and navigation ability. The activity in the left medial temporal areas was positively correlated with task performance, whereas activity in the right parietal area was negatively correlated with task performance. Furthermore, the activity in the bilateral medial temporal areas was positively correlated with scores reflecting preferred navigation strategies, whereas activity in the bilateral superior parietal lobules was negatively correlated with them. Our data suggest that different brain activities related to navigation should reflect navigation skill and strategies.     

Morphological brain changes associated with Schneider's first-rank symptoms in schizophrenia: a MRI study

BACKGROUND: Schneider's first-rank symptoms involve an alienated feature of the sense of one's own mental or physical activity. To clarify the brain morphological basis for the production of these symptoms, volumes of the frontal and medial temporal regions and their clinical correlates were examined in patients with schizophrenia. METHOD: Twenty-two patients with schizophrenia and 44 age- and gender-matched healthy control subjects were included. All patients were in their psychotic episodes with definite Schneiderian symptoms, rated by using the Scale for Assessment of Positive Symptoms. Volumetric measurements of high-resolution magnetic resonance imaging were performed in the prefrontal area, cingulate gyrus, and precentral gyrus, and the medial temporal structures such as the amygdala, hippocampus, and parahippocampal gyrus. RESULTS: Patients had significantly decreased volumes in the cingulate gray matter and the amygdala compared to controls. In the patient group, Schneiderian symptom severity showed significant inverse correlations with volumes of the right posterior cingulate gray matter and of the left anterior parahippocampal gyrus. CONCLUSIONS: Schneiderian symptoms may be associated with morphological abnormalities in the limbic-paralimbic regions such as the cingulate gyrus and parahippocampal gyrus, which possibly serve the self-monitoring function and the coherent storage and reactivation of information.     

Event-related fMRI of word classification and successful word recognition in subjects at genetically enhanced risk of schizophrenia

BACKGROUND: Verbal declarative memory is a core deficit in schizophrenia patients, seen to a lesser extent in unaffected biological relatives. Neuroimaging studies suggest volumetric differences and aberrant function in prefrontal and temporal regions in schizophrenia patients compared to controls. These deficits are also reflected in the small number of similar investigations in unaffected biological relatives. However, it is unclear the extent to which dysfunction is genetically mediated or a feature of the established illness. METHOD: Event-related blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) was used to measure brain activation in 68 biological relatives of schizophrenia patients (of whom 27 experienced transient or isolated psychotic symptoms) and 21 controls during verbal classification and recognition. RESULTS: During word classification, the high-risk group showed a greater response relative to controls in the right inferior frontal gyrus. During correct recognition (relative to correct rejection), the high-risk group showed significantly greater response relative to controls in the right cerebellum. When the high-risk group was split into those with (HR+) and without (HR-) psychotic symptoms, the increased response in the right inferior frontal gyrus was only seen when the HR+ were compared to controls. The greater cerebellar response was seen when both HR groups were compared to controls. CONCLUSIONS: Activation increases in the right inferior frontal gyrus and cerebellum in high-risk subjects compared to controls during a relatively low-load memory task are likely to represent compensation for genetically mediated abnormalities. This is consistent with a leftward shift of the inverted 'U' load-response model of cognitive function in schizophrenia.     

正常人参数性数字n-back工作记忆任务的去激活网络:fMRI研究

目的:探讨工作记忆任务诱发去激活(Task induced deactivation,TID)脑区及其意义。方法:正常受试者35名,采用参数性数字n-back任务(n为1、2、3)行fMRI,0back作为对照任务。根据受试者在实验过程中3back任务的行为学表现,将准确率为≥85%的受试者纳入高执行表现正常受试者(High performing normal subjects,HPNS)组。采用SPM2软件进行功能数据预处理、统计分析和结果显示。结果:HPNS中TID脑区包括:前额叶皮层内侧部(medialprefrontal cortex,MPFC);扣带;右侧额下回(BA47);双侧颞叶多个脑区。在2back负载水平之内,随着负载增加,TID脑区去激活程度增加,但在2back负载之后,大多TID脑区的去激活呈平台期表现。结论:TID网络的存在对WM任务的正确执行是必须的。