静息态fMRI观察左侧基底核区脑梗死特定频段低频振幅改变

目的 探讨左侧基底核区梗死患者在特定频段（slow-4：0.027~0.073 Hz，slow-5：0.010~0.027 Hz）下低频振幅（ALFF）改变，追踪其大脑自发活动纵向变化。方法 对25例左侧基底核区脑梗死患者（梗死组）和26名正常志愿者（对照组）采集静息态fMRI数据；采用混合效应分析，针对梗死组慢性期与梗死组急性期、梗死组慢性期与对照组，分别计算其ALFF值频率间、组间主效应脑区差异；于2个频段下进行事后检验，获得组间有差异脑区。结果 ALFF结果显示，两个频段间存在差异性脑区，slow-4频段激活脑区位于皮层下脑区，slow-5频段激活脑区多位于默认网络。在slow-4频段上，梗死组慢性期与急性期对比，慢性期患者双侧顶上小叶、楔前叶、枕叶及健侧颞叶ALFF值升高，扣带回和辅助运动区ALFF值降低；梗死组慢性期与对照组对比，慢性期患者健侧后扣带回和患侧中央前回ALFF值降低，健侧侧部额叶脑回和额极ALFF值升高。在slow-5频段未见差异脑区。结论 slow-4频段显示左侧基底核区脑梗死患者脑自发活动更为敏感；患者恢复过程中存在脑皮质功能重构。     

遗忘型轻度认知障碍患者默认网络改变:基于后扣带回的脑连接研究

目的 探讨遗忘型轻度认知障碍(aMCI)患者后扣带回(PCC)功能连接的变化。 方法 选取性别、年龄和教育程度相匹配的18例aMCI患者(aMCI组)和20名健康老年人(健康老年组)进行GRE-EPI序列的静息状态fMRI检查,以PCC作为种子点,与全脑其他区域进行基于体素的时间序列相关分析。 结果 aMCI组与PCC有显著连接的脑区包括双侧背外侧前额叶(DLPFC)、左侧内侧前额叶(MPFC)及左侧前扣带回(ACC)、双侧顶下小叶(IPL)、双侧颞中回和双侧楔前叶。健康老年组与PCC有显著连接的脑区包括双侧DLPFC、右侧MPFC及ACC、双侧IPL、双侧颞中回、双侧颞下回和双侧楔前叶。健康老年组较aMCI组在右侧额上回、额中回、额下回的盖部及三角部、MPFC及ACC、颞中回及左侧楔前叶连接增强;aMCI组多个脑区功能连接较健康老年组增强,主要包括左侧半球的扣带回中部、顶上小叶(SPL)、IPL、颞中回及右侧IPL。 结论 PCC是aMCI患者脑代谢最先降低的区域,aMCI的PCC与多个功能区的连接破坏是其情节记忆功能减退的生物学基础,而其连接增强提示功能代偿可能。     

遗忘型轻度认知损伤患者半球间镜像同伦功能连接变化

目的 采用基于体素的功能同伦（VMHC）方法探讨遗忘型轻度认知损伤（aMCI）患者半球间功能连接变化。方法 收集47例aMCI患者（aMCI组）和43名性别、年龄、受教育年限相匹配的正常志愿者（对照组）,采集脑结构MRI和静息态fMRI数据;比较aMCI组与对照组间半球间VMHC变化,获得VMHC改变脑区,并以此为种子点,观察与其他脑区间功能连接的异常,并与临床量表评分进行相关性分析。结果 aMCI组患者双侧额下回、前岛叶皮层、壳核VMHC降低,无VMHC增高脑区。aMCI患者前岛叶皮层与默认网络脑区中的后扣带回、内侧前额叶皮层功能连接增加,与注意控制网络脑区、小脑间功能连接减低。左侧前岛叶与内侧前额叶及后扣带回功能连接增加,与患者听觉词语学习测试中再认评分呈正相关（r=0.38、0.33,P均<0.05）。结论 aMCI患者不仅存在半球间VMHC降低,不同脑网络间功能连接亦存在明显差异,对于理解aMCI患者认知改变及其潜在机制具有重要意义。     

静息态功能MRI全脑信号对左侧基底节区脑梗死患者低频振幅的影响

目的 评价静息态功能MRI（rs-fMRI）全脑信号对左侧基底节区脑梗死患者低频振幅（ALFF）及分数ALFF（fALFF）的影响。方法 纳入21例左侧基底节区脑梗死患者（梗死组）及26名健康志愿者（对照组），于去除和未去除全脑信号2种预处理条件下，根据rs-fMRI数据计算ALFF及fALFF，分析梗死组发病7天内（急性期）与3个月（恢复期）之间、后者与对照组之间ALFF及fALFF存在差异的脑区。结果 未去除全脑信号条件下，梗死组恢复期大脑双侧额上回、后扣带回（PCC）和健侧壳核ALFF均明显低于对照组（P均<0.05），健侧额下回眶部及颞上回颞极ALFF均明显高于对照组（P均<0.05）；梗死组患者恢复期健侧楔叶、颞下回、枕中回ALFF明显高于急性期（P均<0.05）。去除全脑信号条件下，梗死组恢复期健侧额上回、PCC及壳核ALFF均明显低于对照组（P均<0.05），健侧额下回眶部及颞上回ALFF均明显高于对照组（P均<0.05）；梗死组恢复期健侧颞下回ALFF明显高于急性期（P<0.05）。梗死组恢复期与对照组、梗死组内不同时期之间各脑区fALFF未见显著差异（P均>0.05）。结论 左侧基底节区脑梗死患者随运动恢复而发生脑皮质功能代偿；未去除全脑信号条件下可显示更多ALFF存在差异的脑区。     

基于比率低频振幅fMRI评价青少年网络游戏成瘾者静息态下脑功能活动

目的：采用比率低频振幅（fALFF）评价青少年网络游戏成瘾（IGA）者静息态下脑功能区激活特点.方法：对17例符合IGA诊断标准的青少年（IGA组）及19例在年龄、性别、受教育年限、利手等方面相匹配的青少年健康志愿者（正常对照组）行静息态fMRI扫描,两组间fALFF的差异采用两样本t检验.结果：与正常对照组相比,IGA组静息态下双侧额上回及额中回、右侧额内侧回、右侧扣带回前部及左侧扣带回后部、右侧海马旁回、右侧颞下回、右侧楔前叶脑区fALFF增高,差异有统计学意义（P＜0.05,未校正）.右侧颞上回及颞中回、双侧舌回、双侧枕叶、右侧胼胝体压部及双侧小脑脑区fALFF降低,差异有统计学意义（P＜0.05,未校正）.结论：IGA者静息态下脑功能存在异常,fALFF有助于对IGA者静息状态脑功能变化的理解.     

单侧颞叶内侧癫痫伴海马硬化患者脑内在活动改变

目的 观察颞叶内侧癫痫(mTLE)伴海马硬化患者脑内在活动(IBA)改变。方法 纳入38例单侧mTLE伴海马硬化患者(mTLE组)和53名健康志愿者[健康对照(HC)组],比较组间IBA静态指标,包括低频振幅(ALFF)、比率ALFF(fALFF)、局部一致性(ReHo)、度中心性(DC)、全局信号相关性(GSCorr)和体素镜像同伦连接(VMHC)]及其对应动态指标dALFF、dfALFF、dReHo、dDC、dGSCorr及dVMHC,分析其与癫痫持续时间和认知评估量表的相关性。结果 相比HC组,mTLE组双侧丘脑、内侧颞叶、基底核、脑桥及小脑ALFF、dALFF和fALFF值,右侧扣带回及补充运动区fALFF值,右侧内侧颞叶、梭状回及基底核dfALFF值,脑桥、双侧丘脑、双侧尾状核及左侧内侧颞叶ReHo值均升高;左侧颞叶新皮质和额叶fALFF值和dfALFF值,双侧颞叶新皮质ReHo值和DC值,左侧颞叶新皮质dReHo和GSCorr值,双侧颞叶新皮质、小脑及内侧颞叶VMHC值,双侧枕叶、楔叶及补充运动区dVMHC值均降低。mTLE组形状连线测试A耗时与左侧丘脑ALFF值、左侧海马...     

Changes in hippocampal connectivity in the early stages of Alzheimer's disease: evidence from resting state fMRI

A selective distribution of Alzheimer's disease (AD) pathological lesions in specific cortical layers isolates the hippocampus from the rest of the brain. However, functional connectivity between the hippocampus and other brain regions remains unclear in AD. Here, we employ a resting state functional MRI (fMRI) to examine changes in hippocampal connectivity comparing 13 patients with mild AD versus 13 healthy age-matched controls. Hippocampal connectivity was investigated by examination of the correlation between low frequency fMRI signal fluctuations in the hippocampus and those in all other brain regions. We found that functional connectivity between the right hippocampus and a set of regions was disrupted in AD; these regions are: medial prefrontal cortex (MPFC), ventral anterior cingulate cortex (vACC), right inferotemporal cortex, right cuneus extending into precuneus, left cuneus, right superior and middle temporal gyrus and posterior cingulate cortex (PCC). We also found increased functional connectivity between the left hippocampus and the right lateral prefrontal cortex in AD. In addition, rightward asymmetry of hippocampal connectivity observed in elderly controls was diminished in AD patients. The disrupted hippocampal connectivity to the MPFC, vACC and PCC provides further support for decreased activity in "default mode network" previously shown in AD. The decreased connectivity between the hippocampus and the visual cortices might indicate reduced integrity of hippocampus-related cortical networks in AD. Moreover, these findings suggest that resting-state fMRI might be an appropriate approach for studying pathophysiological changes in early AD.     

2型糖尿病患者静息态功能磁共振自发性脑活动改变的Meta分析

目的 通过Meta分析探讨2型糖尿病（T2DM）患者的fMRI静息态脑自发性活动改变规律。方法 检索PubMed、EMbase、中国生物医学文献数据库中已公开发表的有关静息态fMRI（rs-fMRI）研究T2DM患者自发性脑活动改变的文献,并进行文献筛选及资料提取。采用SDM软件对纳入文献的低频振幅（ALFF）值或分数低频振幅（fALFF）值进行基于体素的Meta分析。结果 共6项符合要求的文献纳入分析,包括137例T2DM患者和140例正常对照者。Meta分析结果显示,静息状态下T2DM组患者ALFF、fALFF值减低区域主要集中在右侧枕中回、右侧舌回及左侧嗅皮层;而ALFF、fALFF值增高区域主要为双侧小脑、双侧前扣带回、左侧颞下回。结论 T2DM患者在静息状态下存在自发性脑活动的改变。右侧枕中回、右侧舌回及左侧嗅皮层活动减低可能提示微结构损伤,同时双侧小脑、双侧前扣带回、左侧颞下回活动增强可能提示代偿性改变。     

Localization of cerebral functional deficits in treatment-naive,first-episode schizophrenia using resting-state fMRI

BackgroundSpontaneous low-frequency fluctuations (LFF) in the blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) signal have been shown to reflect cerebral spontaneous neural activity, and the present study attempts to explore the functional changes in the regional brain in patients with schizophrenia using the amplitude of the BOLD signals.MethodsA total of 66 treatment-naïve, first-episode schizophrenia (FES) patients and 66 normal age- and sex-matched controls were recruited. Resting-state fMRIs were obtained using a gradient-echo echo-planar imaging sequence. The amplitude of LFF (ALFF) was calculated using REST software. Voxel-based analysis of the ALFF maps between control and patient groups was performed with twos-sample t-tests using SPM2.ResultsCompared to the controls, the FES group showed significantly decreased ALFF in the medial prefrontal lobe (MPFC) and significant increases in the ALFF in the left and right putamen. Significant positive correlations were observed between ALFF values in the bilateral putamen in both the patient and control groups.ConclusionsAlterations of the ALFF in the MPFC and putamen in FES observed in the present study suggest that the functional abnormalities of those areas are at an early stage of the disease.     

静息态功能磁共振和纤维追踪技术在单纯脊髓受累型多发性硬化患者的临床应用

目的联合应用静息态功能磁共振成像(resting-state functional magnetic resonance imaging,RS-fMRI)和纤维追踪技术探索单纯脊髓受累的多发性硬化患者(multiple sclerosis patients with simple spinal cord involvement,MS-SSCI)脑部功能和脑白质完整性是否有改变。材料与方法利用RS-fMRI比较22例MS-SSCI及22例年龄、性别相匹配的健康对照组的基础脑活动,将组间有差异的区域作为感兴趣区,利用纤维追踪技术重建穿过这些区域的白质纤维束,比较两组之间纤维束的部分各向异性(FA)和表观弥散系数(ADC),最后将MS-SSCI组感兴趣区低频振幅(amplitude of low frequency fluctuation,ALFF)、FA、ADC分别与临床扩展残疾状态量表(expanded disability states scale,EDSS)评分进行Pearson相关分析。结果与健康对照组相比,MS-SSCI组右侧海马ALFF值明显减低,左侧额中回、左侧后扣带回、右侧枕中回ALFF值明显增高(双样本t检验,经AlphaSim校正,P＜0.01,体素大小＞40),MS-SSCI组右侧海马FA值(t右侧海马=2.099, P右侧海马=0.042)和ADC值(t右侧海马=－2.053,P右侧海马=0.047)存在明显差异;MS-SSCI左侧后扣带回ALFF值与EDSS显著相关,结构变化参数与EDSS间无明显相关性(P＞0.05)。结论 MS-SSCI脑内存在功能和结构异常,功能改变与认知障碍密切相关。     

静息态fMRI评估酒精注射急性期恒河猴脑功能改变

目的 采用静息态fMRI基于分数低频振荡幅度（fALFF）算法评价酒精急性期恒河猴脑功能改变。方法 分别对7只雄性健康恒河猴于给予酒精前（对照组）及10 min后（酒精组）行静息态fMRI扫描,采用fALFF算法获得两组fALFF值存在差异的脑区。结果 静息态下,酒精组fALFF值低于对照组的脑区为右枕叶、右侧颞中回、左侧中央后回、右侧楔叶/距状沟、右侧额上回、后扣带回及小脑、丘脑（P<0.01）;酒精组fALFF值高于对照组的脑区包括双侧额上回、双侧颞下回、右侧中央前回、楔前叶、后扣带回、左侧海马、双侧岛叶及脑干、小脑、右侧基底核（P均<0.01）。结论 酒精急性期恒河猴脑功能的改变具有全脑效应。     

原发性失眠的不同频段低频振幅静息态功能磁共振研究

目的 应用静息态低频振幅算法探讨原发性失眠(PI)患者在不同频段(Slow-4:>0.027~0.073 Hz,Slow-5:0.01~0.027 Hz)大脑自发活动的变化。方法 44例PI患者(PI组)及44名年龄、性别匹配的正常睡眠志愿者(对照组)均接受fMRI扫描,应用静息态fMRI数据处理助手(DPARSFA)进行数据预处理,SPM8软件包进行全因素方差分析PI组和对照组及不同频段脑功能活动特点。之后,对PI组和对照组采用两样本t检验分别观察两个频段ALFF值差异,同时分析ALFF值差异脑区与临床量表的相关性。结果 不同频段间一些脑区的ALFF值存在差异,包括双侧尾状核头、双侧岛叶、双侧颞上回、双侧内侧额叶、双侧眶额皮质、双侧颞下回(P<0.01,AlphaSim校正)。与对照组相比,PI组双侧小脑后叶、左侧额上回、内侧额叶ALFF减低,而左侧颞中回、右侧颞上回、双侧后扣带回、双侧楔前叶ALFF增高(P<0.01,AlphaSim校正)。此外,Slow-5频段更容易发现PI患者异常的大脑自发活动。结论 PI患者存在多个脑区神经元的自发活动异常且具有频率相关性。     

广泛性焦虑障碍发病机制的静息态功能磁共振成像

目的 应用静息态功能磁共振成像(rs-fMRI)观察广泛性焦虑障碍(GAD)患者全脑活动及网络连接的变化,探索其与临床焦虑症状的相关性。方法 对28例GAD患者(GAD组)、28名健康对照(HC)组进行fMRI扫描。逐体素对比分析两组低频振幅(ALFF)和种子点静息态功能连接(FC)的差异,采用Pearson相关分析研究其与焦虑自评量表、汉密尔顿焦虑量表(HAM-A)、GAD-7项量表和汉密尔顿抑郁量表等评分的相关性。结果 GAD组双侧背内侧前额叶、左楔前叶/后扣带回和双侧背外侧前额叶ALFF值明显高于HC组(P均<0.05)。GAD组右侧眶额叶/岛叶-背内侧前额叶、左侧眶额叶/岛叶-背内侧前额叶、左侧背外侧前额叶皮层-右侧海马的功能连接与HAM-A评分和GAD-7评分均有相关性。结论 背侧前额叶皮层及楔前叶/后扣带回脑活动、前额叶-边缘组织回路异常可能是GAD重要的发病机制。     

基于静息态MRI观察比率低频振幅下产后抑郁症患者脑自发神经活动

目的 采用静息态功能MRI（fMRI）观察产后抑郁症（PPD）患者在比率低频振幅（fALFF）下大脑自发神经活动。方法 对23例产后抑郁症患者（PPD组）、28名健康产妇（HPW组）及20例女性重性抑郁障碍患者（MDD组）采集静息态fMRI数据，以fALFF技术观察各组脑自发神经活动，提取PPD组与HPW组差异脑区的fALFF值，与爱丁堡产后抑郁量表（EPDS）评分进行相关性分析。结果 相比HPW组，PPD组左侧后扣带回、左侧楔前叶、左侧枕中回、左侧枕下回及右侧距状裂周围皮质fALFF值增高（AlphaSim校正，P均<0.05），右侧眶部额下回、右侧脑岛、右侧嗅皮质、右侧海马fALFF值减低（AlphaSim校正，P均<0.05）。相比MDD组，PPD组右侧舌回、右侧小脑fALFF值增高（AlphaSim校正，P均<0.05），右侧背外侧前额叶、右侧楔前叶、左侧顶上回、左侧角回、右侧内侧旁扣带回、右侧颞下回fALFF值减低（AlphaSim校正，P均<0.05）。PPD组右侧眶部额下回fALFF值与EPDS评分呈负相关（r=-0.53，P=0.01）。结论 静息态下PPD患者与情绪、认知相关脑区存在自发神经活动异常，其右侧眶部额下回fALFF值与抑郁严重程度密切相关；PPD与MDD患者脑fALFF表现并不完全一致，PPD可能存在特征性神经功能改变。     

Abnormal insula functional network is associated with episodic memory decline in amnestic mild cognitive impairment

Abnormalities of functional connectivity in the default mode network (DMN) recently have been reported in patients with amnestic mild cognitive impairment (aMCI), Alzheimer's disease (AD) or other psychiatric diseases. As such, these abnormalities may be epiphenomena instead of playing a causal role in AD progression. To date, few studies have investigated specific brain networks, which extend beyond the DMN involved in the early AD stages, especially in aMCI. The insula is one site affected by early pathological changes in AD and is a crucial hub of the human brain networks. Currently, we explored the contribution of the insula networks to cognitive performance in aMCI patients. Thirty aMCI and 26 cognitively normal (CN) subjects participated in this study. Intrinsic connectivity of the insula networks was measured, using the resting-state functional connectivity fMRI approach. We examined the differential connectivity of insula networks between groups, and the neural correlation between the altered insula networks connectivity and the cognitive performance in aMCI patients and CN subjects, respectively. Insula subregional volumes were also investigated. AMCI subjects, when compared to CN subjects, showed significantly reduced right posterior insula volumes, cognitive deficits and disrupted intrinsic connectivity of the insula networks. Specifically, decreased intrinsic connectivity was primarily located in the frontal-parietal network and the cingulo-opercular network, including the anterior prefrontal cortex (aPFC), anterior cingulate cortex, operculum, inferior parietal cortex and precuneus. Increased intrinsic connectivity was primarily situated in the visual-auditory pathway, which included the posterior superior temporal gyrus and middle occipital gyrus. Conjunction analysis was performed; and significantly decreased intrinsic connectivity in the overlapping regions of the anterior and posterior insula networks, including the bilateral aPFC, left dorsolateral prefrontal cortex, dorsomedial prefrontal cortex, and anterior temporal pole was found. Furthermore, the disrupted intrinsic connectivity was associated with episodic memory (EM) deficits in the aMCI patients and not in the CN subjects. These findings demonstrated that the functional integration of the insula networks plays an important role in the EM process. They provided new insight into the neural mechanism underlying the memory deficits in aMCI patients.     

Regional coherence changes in the early stages of Alzheimer's disease: a combined structural and resting-state functional MRI study

Recent functional imaging studies have indicated that the pathophysiology of Alzheimer's disease (AD) can be associated with the changes in spontaneous low-frequency (<0.08 Hz) blood oxygenation level-dependent fluctuations (LFBF) measured during a resting state. The purpose of this study was to examine regional LFBF coherence patterns in early AD and the impact of regional brain atrophy on the functional results. Both structural MRI and resting-state functional MRI scans were collected from 14 AD subjects and 14 age-matched normal controls. We found significant regional coherence decreases in the posterior cingulate cortex/precuneus (PCC/PCu) in the AD patients when compared with the normal controls. Moreover, the decrease in the PCC/PCu coherence was correlated with the disease progression measured by the Mini-Mental State Exam scores. The changes in LFBF in the PCC/PCu may be related to the resting hypometabolism in this region commonly detected in previous positron emission tomography studies of early AD. When the regional PCC/PCu atrophy was controlled, these results still remained significant but with a decrease in the statistical power, suggesting that the LFBF results are at least partly explained by the regional atrophy. In addition, we also found increased LFBF coherence in the bilateral cuneus, right lingual gyrus and left fusiform gyrus in the AD patients. These regions are consistent with previous findings of AD-related increased activation during cognitive tasks explained in terms of a compensatory-recruitment hypothesis. Finally, our study indicated that regional brain atrophy could be an important consideration in functional imaging studies of neurodegenerative diseases.     

膝骨关节炎和腰痛患者的脑低频振幅影像学特征比较北大核心CSCD

目的基于静息态功能磁共振成像低频振幅(ALFF)分析方法探讨膝骨关节炎(KOA)和腰痛两种慢性疼痛患者脑影像学特征的异同。方法2015年8月至2021年9月在福建福州市各社区招募KOA患者16例及年龄、性别相似的健康人16例(对照组1);从Openpain数据库获得27例腰痛患者和年龄、性别相似的健康人32例(对照组2)。比较受试者的ALFF。采用简明疼痛量表(BPI)对KOA患者进行疼痛评分,采用视觉模拟量表(VAS)对腰痛患者进行疼痛评分,并与ALFF进行相关性分析。结果与各自对照组相比,KOA和腰痛患者左前脑岛ALFF降低,KOA患者海马和后扣带回ALFF降低,腰痛患者升高;KOA患者左楔前叶、左中扣带回、右中脑导水管周围灰质区域ALFF降低,右中央前回、中央后回ALFF升高;腰痛患者双前扣带回、双眶部额前回、左背外侧前额叶、右内侧前额叶ALFF降低,右海马旁回、右杏仁核ALFF升高;KOA患者左中扣带回ALFF与BPI评分负相关(r=-0.73,P=0.003),腰痛患者右海马/杏仁核ALFF与VAS评分正相关(r=0.73,P=0.003)。结论不同类型慢性疼痛有共同和特异的脑影像学特征。前脑岛、海马和后扣带回ALFF改变可能是KOA和腰痛的共同病理机制。     

多系统萎缩患者轻度认知功能障碍的静息态低频振幅研究

目的采用静息态功能磁共振成像(resting state functional MRI,rs-fMRI)低频振幅(amplitude of low-frequency fluctuation,ALFF)方法探究多系统萎缩(multiple system atrophy,MSA)患者认知相关的自发脑活动改变。材料与方法对29例认知功能正常的MSA患者(MSA-normal cognition,MSA-NC)、33例伴轻度认知功能障碍的MSA患者(MSA-mild cognitive impairment,MSA-MCI)与33名健康对照者(healthy control,HC)进行rs-fMRI扫描。应用ALFF方法比较各组间自发脑活动改变,并对患者组间存在差异脑区的ALFF值与认知评分进行相关性分析。结果与HC相比,MSA-NC在左侧角回及右侧颞中回出现ALFF增强;与HC相比,MSA-MCI在双侧背外侧前额叶、内侧前额叶、前扣带回、中扣带回出现ALFF减低,而在双侧颞下回、角回、左侧枕中回、右侧颞中回、楔前叶及右侧小脑、小脑蚓出现ALFF增强。与MSA-NC相比,MSA-MCI在右侧额叶皮层出现ALFF减低,并与蒙特利尔认知评估量表(montreal cognitive assessment scale,MoCA)评分呈正相关(r=0.531,P<0.05);在右侧小脑出现ALFF增强,并与MoCA评分呈负相关(r=-0.499,P<0.05)。结论MSA特异的轻度认知功能障碍是由小脑与额叶皮层损伤共同介导,其中小脑起到代偿作用。     

An fMRI study of differential neural response to affective pictures in schizophrenia

Although emotional dysfunction is considered a fundamental symptom of schizophrenia, studies investigating the neural basis of emotional dysfunction in schizophrenia are few. Using functional magnetic resonance imaging (fMRI) and a task viewing affective pictures, we aimed to examine automatic emotional response and to elucidate the neural basis of impaired emotional processing in schizophrenia. Fifteen healthy volunteers and 15 schizophrenics were studied. During the scans, the subjects were instructed to indicate how each of the presented pictures made them feel. Whole brain activities in response to the affective pictures were measured by fMRI. Controls recruited the neural circuit including amygdaloid-hippocampal region, prefrontal cortex, thalamus, basal ganglia, cerebellum, midbrain, and visual cortex while viewing unpleasant pictures. Despite an equal behavioral result to controls, the patients showed less activation in the components of the circuit (right amygdala, bilateral hippocampal region, medial prefrontal cortex (MPFC), basal ganglia, thalamus, cerebellum, midbrain, and visual cortex). This study demonstrated functional abnormalities in the neural circuit of emotional processing in schizophrenia. In particular, decreased activation in the right amygdala and MPFC appears to be an important finding related to dysfunctional emotional behavior in schizophrenia.     

2型糖尿病伴轻度认知功能障碍患者脑静息态功能MRI研究

目的探讨2型糖尿病(T2DM)伴轻度认知功能障碍(MCI)患者脑静息态脑功能局部一致性(Re Ho)及分数低频波动振幅(f ALFF)的改变特点。材料与方法共纳入21名T2DM伴MCI患者(D-MCI组)及25名年龄、性别、受教育水平相匹配的对照组志愿者(HC组),通过3.0 T MR仪采集T2WI、FLAIR、三维T1WI结构数据和静息态功能数据,分别计算静息态Re Ho值和f ALFF值并进行组内和组间比较,然后提取组间存在显著差异脑区的Re Ho/f ALFF值与临床数据做相关分析。结果 D-MCI组存在多个右侧额上回亚区、部分小脑Re Ho值显著增高,双侧内侧眶额部额上回、右侧额中回、右侧颞下回、左侧枕中回及右侧舌回Re Ho值显著减低;而左侧颞下回、双侧扣带回前部f ALFF值显著增高,右侧舌回f ALFF值显著减低。D-MCI组Hb A1c与扣带回前部f ALFF值(r=-0.482,P=0.027)、Mo CA评分与左侧颞下回f ALFF值(r=-0.547,P=0.010)呈显著负相关。结论 T2DM伴MCI患者存在认知控制网络、视觉信息处理、语义认知等多个相关脑区的异常活动,这些异常活动可部分阐释T2DM患者伴发MCI的神经生理基础。