轻度认知损害和阿尔茨海默病的大脑灰质体积及其与记忆功能的关系

目的考察轻度认知损害(mild cognitive impairment,MCI)和阿尔茨海默病(Alzheimer’s disease,AD)的大脑灰质体积是否存在异常及其与记忆功能的关系。方法本研究共纳入56例轻度AD、14例MCI和16例正常对照,所有被试均进行了记忆功能测查和磁共振影像检查。影像数据分析采用患者基于体素的脑形态学分析(voxel-based morphometry,VBM)。结果 AD组和MCI组记忆测验评分下降,呈AD组相似文献   

基于体素的MRI形态学测量及ApoE基因检测在遗忘型轻度认知障碍诊断中的应用

目的 应用基于体素的核磁共振(MRI)形态学测量技术及基因检测技术,分析遗忘型轻度认知障碍(aMCI)相对于正常老年人脑灰质体积改变的特点、载脂蛋白E(ApoE)基因多态性并探讨上述改变与aMCI发病机制可能的相关性,为aMCI的早期诊断、早期干预提供依据。方法 临床招募年龄、性别、族别、文化程度、生活背景等相互匹配并确定无血缘关系的14例aMCI患者、15例正常老年人,用3.0T磁共振进行三维T₁WI扫描,利用基于SPM12的DARTEL工具箱对扫描获得的结构图像进行预处理,再对aMCI组和对照组的全脑灰质体积进行基于体素的统计学比较。通过检测静脉血中ApoE基因,鉴定每个样本ApoE基因的等位基因及基因型。将上述所得数据进行相关统计学分析。结果 aMCI组中ε3/ε4基因型与正常对照组相比差异有统计学意义(P<0.05)。aMCI组与对照组比较,脑灰质萎缩主要位于左侧顶上小叶、左侧岛叶、岛叶前部、中央后回、腹内侧前额叶,右侧角回。结论 证实了aMCI患者患病与ApoE基因多态性存在联系,ApoEε4可能为aMCI的危险因素,aMCI患者灰质萎缩主要位于顶...     

强迫障碍患者脑灰质体积改变及其与认知功能和临床症状的相关性

目的比较强迫障碍患者脑灰质体积与健康对照的差异,并分析患者脑灰质体积有改变脑区与认知功能和临床症状的关系。方法选取首发强迫障碍患者36例和年龄、性别、受教育程度相匹配的健康对照35名,进行头部磁共振扫描,采用基于体素的形态学分析测量受试者大脑灰质体积,患者组使用神经认知成套测验和耶鲁—布朗强迫症状量表(Yale-Brown obsessive-compulsive scale,Y-BOCS)评估认知功能和强迫症状。结果与对照组相比,患者组脑灰质体积增加的脑区有额顶叶(左侧中央后回、左侧中央前回)(t=4.299,P0.0005,体素100)、颞叶—边缘系统(左侧梭状回、左侧颞上回、左侧颞中回、左侧海马旁回)(t=4.841,P 0.0005,体素100);脑灰质体积减少的脑区为双侧前扣带回(t=-4.181,P0.0005,体素100)。患者组中,颞叶—边缘系统的灰质体积与社会认知评分正相关(r=0.347,P=0.038),前扣带回的灰质体积与强迫思维评分正相关(r=0.416,P=0.012)。结论强迫障碍患者在额顶叶、颞叶—边缘系统、双侧前扣带回等广泛的脑区存在灰质体积改变,其中颞叶—边缘系统灰质体积与社会认知、前扣带回灰质体积与强迫思维存在关联。     

3.0T常规磁共振阴性药物难治性颞叶癫痫脑灰质及结构网络研究

目的探讨3.0T常规磁共振阴性的药物难治性颞叶癫痫(rTLE-N)与药物控制性颞叶癫痫(cTLE-N)脑灰质体积及脑白质结构网络拓扑属性差异。方法选取2017年3月至2019年8月在广西医科大学第一附属医院就诊的20例rTLE-N、15例cTLE-N完成头颅3DT1及DTI扫描,20例健康对照(HC)也完成此项检查。基于体素的形态学分析(VBM)方法比较3组脑灰质体积差异,基于图论的方法比较3组脑白质结构网络拓扑属性差异。结果①VBM结果:与HC组相比,rTLE-N组在双侧海马、丘脑、颞中回、内侧和旁扣带回,左侧直回、眶内额上回,右侧海马旁回灰质体积减少(P<0.001);cTLE-N组右侧颞中回、眶内额上回灰质体积减少(P<0.001)。与cTLE-N组相比,rTLE-N组在双侧岛叶、中央沟盖,左侧海马旁回、眶内额上回、梭状回、小脑6区,右侧丘脑、枕下回灰质体积减少(P<0.001);②脑白质结构网络拓扑属性结果:3组脑白质结构网络均表现出小世界属性。与HC组比较,rTLE-N组最短路径长度(Lp)增加、局部效率(Eloc)及全局效率(Eg)下降(P<0.05),cTLE-N组Lp增加、Eg下降(P<0.05);与cTLE-N组比较,rTLE-N组Lp增加、Eloc及Eg下降(P<0.05)。结论TLE-N是一种脑网络疾病,但rTLE-N与cTLE-N致痫网络不同,cTLE-N脑灰质萎缩较局限但已出现脑结构网络拓扑属性受损,而rTLE-N涉及多个脑区灰质萎缩且脑结构网络拓扑属性损害更严重。     

轻度认知障碍和轻度Alzeimer病的海马体积MRI测量

目的研究轻度认知功能障碍（mildcognitiveimpairment,MCI）和轻度阿尔兹海默病（A1zheimerdisease,AD）患者的海马体积萎缩情况,评价利用影像学测定海马体积对MCI、AD的诊断价值。方法应用3．0T磁共振分别对20例MCI患者,20例轻度AD患者,20例认知功能正常的对照者的海马体积进行测量,所得数值用头颅体积进行标准化处理。采用计算机SPSS13．0统计学软件进行资料的统计学处理,比较三组之间体积的差异。结果对照组与MCI组,对照组与AD组的两侧海马体积均存在显著的统计学差异,轻度AD与MCI组两侧的海马体积无显著的统计学差异。结论认知功能障碍与海马体积具有一定的相关性,海马萎缩对早期认知障碍有一定的诊断意义。     

不同发作类型内侧颞叶癫灰质改变的结构性磁共振成像研究

目的探讨不同发作类型内侧颞叶癫患者灰质体积变化及其与病程的相关性。方法共40例内侧颞叶癫患者[部分性发作20例(m TLE-PS组)和继发性全面性发作20例(m TLE-s GS组)]以及20例性别、年龄相匹配的正常对照者行头部T1-三维磁化准备快速梯度回波扫描,采用基于体素的形态学分析进行灰质结构分割,选取双侧额叶和丘脑作为兴趣区,比较3组受试者各脑区灰质体积,采用Spearman秩相关分析探讨内侧颞叶癫患者各脑区灰质体积与病程的相关性。结果 3组受试者双侧额上回、右侧额中回、右侧额内侧回、右侧角回、右侧颞中回、右侧海马、双侧丘脑和双侧小脑半球灰质体积差异有统计学意义(均P0.01,FWE校正),与正常对照组相比,m TLE-PS组双侧额上回、小脑半球和右侧颞中回、海马、丘脑灰质体积减少(均P0.01,FWE校正),m TLE-s GS组双侧额上回、丘脑、小脑半球和右侧角回、颞中回、海马灰质体积减少(均P0.01,FWE校正);与m TLE-PS组相比,m TLE-s GS组双侧额上回、丘脑和右侧额内侧回、直回灰质体积减少(均P0.01,FWE校正)。m TLE-s GS组患者左侧额上回(rs=-0.611,P=0.004)和右侧额中回(rs=-0.562,P=0.010)与病程呈负相关关系。结论不同发作类型内侧颞叶癫患者均存在双侧额叶、丘脑、小脑半球和右侧颞叶、海马灰质损伤,但损伤脑区有所不同,继发性全面性发作患者以双侧额叶和丘脑灰质体积减少为主,提示丘脑-皮质环路是内侧颞叶癫继发性全面性发作的重要结构基础。     

轻度认知障碍的海马、内嗅体积变化研究

目的研究轻度认知功能障碍(MCI)和阿尔兹海默病(AD)患者的海马、内嗅体积萎缩情况,评价利用高分辨影像学测定海马、内嗅体积对MCI、AD的诊断及预测价值。方法应用西门子3.0T磁共振分别对32例MCI患者,25例AD患者,32例正常的对照者进行3D T1WI扫描,并用freesurfer软件计算三组海马、内嗅体积,后用SPSS 17.0统计学软件进行资料的统计学处理,比较三组之间灰质体积的差异。评价在判断MIC中的价值。结果与对照组比较,MCI组[左侧(3.07±0.56)cm3,右侧(3.24±0.61)cm3]、AD组[左侧(2.81±0.64)cm3,右侧(3.01±0.67)cm3]的海马体积萎缩,其差异有统计学意义(P<0.01),且AD组比MCI组在海马体积(左侧0.26 cm3,右侧0.23cm3)均值上有更明显的萎缩;海马体积减小的程度与简易智能检查量表(MMSE)积分呈正相关性,而内嗅的体积变化在三组间的比较无统计学差异。结论通过Freesurfer测量的MRI形态学研究能够客观揭示AD早期阶段海马体积的萎缩改变,且海马体积萎缩与MMSE积分相结合对轻度认知障碍的诊断更准确。     

帕金森病患者脑灰质变化的VBM-MRI研究

目的应用核磁共振的基于体素形态学(voxel-based morphometry method of magnetic resonanceimaging,VBM-MRI)技术,研究帕金森病(Parkinson disease,PD)患者大脑灰质变化的状况。方法 28例PD组与年龄、受教育年限相匹配32例健康对照组的VBM-MRI图像数据进行比较,PD组中,早期PD组(early Parkinson disease,EPD,n=14)与晚期PD组((late Parkinson disease,LPD,n=14)的VBM-MRI图像数据进行比较。结果与健康对照组比较,VBM-MRI显示PD组患者存在下列脑区灰质体积减少:额叶(双侧额上回、左额下回)、双侧颞叶(颞上回、颞中回)、右侧扣带回、右侧丘脑、双侧尾状核及左顶下小叶。与EPD比较,VBM-MRI显示LPD在下列脑区存在灰质体积减少:额叶(双侧额上回、右侧额下回、右侧额叶眶部、双侧内侧前额叶),颞叶(右侧颞上回、左侧颞中回),右侧海马旁回、右侧尾状核、右侧下丘脑,差异均有显著统计学意义。结论本组PD患者的脑灰质改变,主要集中在额叶、颞叶、右侧扣带回及皮质下的灰质。随着PD病程进展,这些部位的灰质减少加剧,并在边缘叶有进展的趋势。     

早期帕金森病患者非运动症状与脑结构异常的观察

目的 分析早期帕金森病(PD)患者非运动症状(NMS)的特点及相关脑灰质结构异常.方法 对34例早期原发性PD患者的NMS数量进行记录,并与年龄、病程、病情严重程度及帕金森病统一评价量表(UPDRSⅢ评分)等进行相关分析.应用3D-T1WI脑容积扫描序列对PD患者与25名健康对照进行扫描,采用基于体素的形态学测量(VBM)方法进行数据处理得到全脑灰质图像.结果 PD组患者NMS数量显著高于对照组,且与年龄、病程及MoCA评分无相关性;与UPDRSⅢ评分、H-Y分期呈正相关;与MMSE呈负相关.PD组患者双侧额叶中下回、双侧岛叶、右侧颞中回、右侧楔叶、舌回;左侧颞上回、颞横回灰质不同程度萎缩,双侧额叶萎缩与NMS评分呈正相关.结论 NMS可在早期PD患者中出现,提示PD是累及多系统的神经系统变性病,且PD患者的NMS数量与脑灰质体积缺失关系密切.     

遗忘型轻度认知损害患者海马三维磁共振影像特点

目的 运用基于海马表面的形态分析技术,探讨遗忘型轻度认知损害(aMCI)患者的海马三维MRI特点.方法 对15例aMCI患者和16名年龄及教育程度相匹配的对照,行头颅三维MRI扫描,数据采集后采用InsightSNAP 1.4.1软件在可视三维窗口下选取冠状位逐层勾勒海马轮廓,计算机自动计算海马体积后,进行两组间海马体积的统计学分析;将海马磁共振影像经过三维网格重建,其曲面网格参数化为400×200的点,将各点到中轴线的径向距离进行两组间比较,获得左右海马径向距离t值图;再经多重比较校正后,获得aMCI组与健康对照组问的三维海马形态差异图.结果 左侧海马标化平均体积aMCI组(3247.5±600.2)mm3、健康对照组(3467.9±451.3)mm3,两者差异无统计学意义(t=1.161,P=0.255).右侧海马标化平均体积aMCI组(3416.8±699.1)mm3、健康对照组(3469.1±358.9)mm3,两者差异亦无统计学意义(U=0.178,P=0.859).运用基于海马表面的形态分析技术得到两组间三维海马形态差异图,结果显示aMCI组与健康对照组相比双侧海马的外侧及下表面(组织学上的CA1区和下托)明显萎缩.结论 aMCI患者海马体积未见显著性减小,但通过基于海马表面的形态分析,发现aMCI患者的海马部分区域形态有一定程度的萎缩,以双侧海马外侧及下表面的区域性萎缩为主.这一结果可能反映了aMCI的早期影像学标志.     

Quantitative meta-analysis of gray matter abnormalities in semantic dementia

Cumulative evidence of gray matter abnormalities in semantic dementia (SD) has been reported using voxel-based morphometry (VBM). However, these studies have not been reviewed quantitatively. To estimate gray matter changes in SD quantitatively, we systematically searched whole-brain VBM studies comparing SD patients with healthy controls in the PubMed, ISI Web of Science, and EMABSE databases from January 1990 to August 2011. Coordinates with significant differences between the gray matter volumes of SD patients and healthy controls were extracted from clusters. Meta-analysis was performed using anatomic likelihood estimation. Seven studies, with 68 SD patients and 167 healthy controls, were included. Gray matter volume reductions were found in bilateral fusiform and inferior temporal gyri, extending to the medial portion of the temporal lobes (including amygdala and parahippocampal gyri), left temporal pole, middle temporal gyrus, and caudate. No significant increase in gray matter volume was found. Our findings provide strong evidence of atrophy in bilateral temporal lobes with predominate impairment on the left side, parahippocampal gyrus/amygdala, and left caudate, representing the pathophysiology of SD.     

首发精神分裂症患者的脑灰质减少

目的 采用基于体素的形态学(VBM)分析方法对高分辨磁共振图像进行分析,研究首发精神分裂症患者大脑灰质变化,探讨患者脑灰质改变与临床症状之间的关系.方法 对符合CCMD-3诊断标准的首发精神分裂症患者以及健康志愿者各16例进行脑结构核磁共振扫描,并应用VBM进行脑灰质体积分析.所有患者均完成阳性与阴性症状量表(PANSS)评估.结果 与健康对照相比,患者组灰质密度降低的脑区有右侧小脑(t=5.17,P＜0.001)、右侧顶上回(t=5.01,P＜0.001)、左侧颞上回至岛叶被盖(t=4.79,P＜0.001)、左侧额中回(t=4.71,P＜ 0.001)、左侧额下回(t=4.70,P＜0.001)、右侧舌回(t=4.62,P＜ 0.001)、左侧海马杏仁体(t=4.11,P＜0.001).患者组左侧Heschl's回的灰质密度与PANSS量表总分(r=-0.509,P=0.044)以及PANSS阳性症状量表得分(r=-0.554,P=0.026)呈显著负相关.结论 首发精神分裂症患者的脑灰质减少以左侧额、颞叶为主,其中左侧Heschl's回灰质变化与患者的精神病性症状有相关性.     

弥散张量成像技术预测遗忘型轻度认知障碍患者向老年性痴呆转化的随访研究

目的:探讨弥散张量成像技术(diffusion tensor imaging,DTI)对遗忘型轻度认知功能障碍(aMCI)向老年性痴呆(AD)转化的预测作用。方法:41例aMCI患者(aMCI组)常规予核磁共振(MRI)和DTI扫描,测定感兴趣区的各向异性分数(fractional anisotropy,FA)和表观扩散系数(apparent diffusion coefficient,ADC),以20名老年健康志愿者作为对照(正常对照组)并随访1~3年。结果:与正常对照组比较,aMCI组41例患者中有22例扣带束FA基线值偏低(P0.05),随访1~3年后,其中有19例转化为AD;另外19例扣带束FA值正常的aMCI患者只有2例转化为AD。与非转化AD者比较,AD转化者前额叶、颞叶、海马、下额枕束、胼胝体膝部和扣带束等部位FA值降低(P均0.01),颞叶、海马等部位ADC值升高(P均0.05)。结论:DTI技术具有预测aMCI向AD转化的作用,aMCI患者扣带束FA值低可能是aMCI向AD转化的敏感指标。     

Structural changes in the gray matter of unmedicated patients with obsessive-compulsive disorder: a voxel-based morphometric study

The aim of the current study was to use whole brain voxel-based morphometry（VBM）to assess the gray matter（GM）changes in unmedicated patients with obsessive-compulsive disorder（OCD）compared with normal controls.We compared the GM volumes in28 patients with 22 matched healthy controls using a1.5T MRI.Three-dimensional T1-weighted magnetic resonance images were obtained from all participants.VBM was performed to detect GM volume differences between the two groups.We detected increased regional GM volumes in the bilateral middle temporal gyri,bilateral middle occipital gyri,bilateral globus pallidus,right inferior parietal gyrus,left superior parietal gyrus,right parahippocampus,right supramarginal gyrus,right medial superior frontal gyrus,and left inferior frontal opercular cortex in the OCD patients relative to controls（P〈0.001,uncorrected,cluster size〉100 voxels）.No decreased GM volume was found in the OCD group compared with normal controls.Our findings suggest that structural changes in the GM are not limited to fronto-striato-thalamic circuits in the pathogenesis of OCD.Temporo-parietal cortex may also play an important role.     

阿尔茨海默病颞干纤维束扩散张量成像研究

目的应用扩散张量成像(DTI)研究阿尔茨海默病和遗忘型轻度认知损害患者白质和颞干纤维束部分各向异性(FA)值变化特点,探讨颞干纤维束损伤机制及其对阿尔茨海默病和遗忘型轻度认知损害的诊断与鉴别诊断价值。方法应用常规MRI和DTI测量阿尔茨海默病(10例)、遗忘型轻度认知损害(10例)和正常对照者(10例)颞干纤维束(包括前连合、钩束、额枕下束)及前额叶、颞叶、顶叶、枕叶白质FA值,比较各组受试者左右侧对称部位白质和颞干纤维束FA值变化。结果各组受试者左右侧对称部位白质和颞干纤维束FA值差异无统计学意义(均P0.05),但其前连合、钩束、额枕下束及前额叶白质FA值差异具有统计学意义(均P0.05)。其中,阿尔茨海默病组前连合、钩束、额枕下束FA值低于遗忘型轻度认知损害组(均P0.05),前连合、钩束、额枕下束及前额叶、顶叶白质FA值低于正常对照组(均P0.05);而遗忘型轻度认知损害组与正常对照组前连合、钩束、额枕下束及前额叶白质FA值差异无统计学意义(均P0.05)。结论阿尔茨海默病和遗忘型轻度认知损害患者与正常老年人颞干纤维束FA值存在显著差异,提示颞干纤维束在阿尔茨海默病患者白质损伤中具有重要意义,DTI检查有助于阿尔茨海默病与遗忘型轻度认知损害和正常老龄化的鉴别诊断。阿尔茨海默病前连合、钩束、额枕下束及前额叶、顶叶白质FA值异常具有良好的临床诊断价值。     

Differences in grey and white matter atrophy in amnestic mild cognitive impairment and mild Alzheimer's disease

Background:  Grey matter (GM) atrophy has been demonstrated in amnestic mild cognitive impairment (aMCI) and mild Alzheimer's disease (AD), but the role of white matter (WM) atrophy has not been well characterized. Despite these findings, the validity of aMCI concept as prodromal AD has been questioned.
Methods:  We performed brain MRI with voxel-based morphometry analysis in 48 subjects, aiming to evaluate the patterns of GM and WM atrophy amongst mild AD, aMCI and age-matched normal controls.
Results:  Amnestic mild cognitive impairment GM atrophy was similarly distributed but less intense than that of mild AD group, mainly in thalami and parahippocampal gyri. There were no difference between aMCI and controls concerning WM atrophy. In the mild AD group, we found WM atrophy in periventricular areas, corpus callosum and WM adjacent to associative cortices.
Discussion:  We demonstrated that aMCI might be considered a valid concept to detect very early AD pathology, since we found a close proximity in the pattern of atrophy. Also, we showed the involvement of WM in mild AD, but not in aMCI, suggesting a combination of Wallerian degeneration and microvascular ischaemic disease as a plausible additional pathological mechanism for the discrimination between MCI and AD.     

~(11)C-PIBPET和~(18)F-FDGPET显像诊断阿尔茨海默病与遗忘型轻度认知损害的临床价值

目的应用11C-PIB PET和18F-FDG PET显像研究阿尔茨海默病和遗忘型轻度认知损害患者β-淀粉样蛋白(Aβ)沉积与葡萄糖代谢之间的关系,联合载脂蛋白E(ApoE)基因型进一步探讨遗忘型轻度认知损害与阿尔茨海默病的相关性。方法利用PET显像对阿尔茨海默病(14例)、遗忘型轻度认知损害(10例)和正常对照者(5例)脑组织Aβ沉积和葡萄糖代谢变化进行分析,采用聚合酶链反应-限制性片段长度多态性方法对ApoE基因型进行分析。结果阿尔茨海默病组患者11C-PIB标准化摄取比值在下顶叶、颞叶外侧、额叶、后扣带回皮质和楔前叶、枕叶和纹状体均高于正常对照组(P0.05);遗忘型轻度认知损害组患者脑组织11C-PIB结合水平呈双峰形。11C-PIB+aMCI亚组与阿尔茨海默病组、11C-PIB-aMCI亚组与正常对照组之间11C-PIB标准化摄取比值差异均无统计学意义(P0.05)。18F-FDG PET显像显示,3/5例11C-PIB+aMCI亚组患者双侧顶叶、颞叶和楔前叶代谢减低,其中2例ApoEε4等位基因携带者随访期间进展至阿尔茨海默病;3/5例11C-PIB-aMCI亚组患者双侧额叶和前扣带回代谢减低。结论11C-PIB PET显像是筛查具有阿尔茨海默病病理特点的遗忘型轻度认知损害患者的有效工具。具有阿尔茨海默病病理特征的遗忘型轻度认知损害患者可伴有顶叶、颞叶外侧皮质和楔前叶代谢减低,其中ApoEε4等位基因携带者更易进展至阿尔茨海默病痴呆。     

Correlation between white matter damage and gray matter lesions in multiple sclerosis patients

We observed the characteristics of white matter fibers and gray matter in multiple sclerosis patients, to identify changes in diffusion tensor imaging fractional anisotropy values following white matter fiber injury. We analyzed the correlation between fractional anisotropy values and changes in whole-brain gray matter volume. The participants included 20 patients with relapsing-remitting multiple sclerosis and 20 healthy volunteers as controls. All subjects underwent head magnetic resonance imaging and diffusion tensor imaging. Our results revealed that fractional anisotropy values decreased and gray matter volumes were reduced in the genu and splenium of corpus callosum, left anterior thalamic radiation, hippocampus, uncinate fasciculus, right corticospinal tract, bilateral cingulate gyri, and inferior longitudinal fasciculus in multiple sclerosis patients. Gray matter volumes were significantly different between the two groups in the right frontal lobe(superior frontal, middle frontal, precentral, and orbital gyri), right parietal lobe(postcentral and inferior parietal gyri), right temporal lobe(caudate nucleus), right occipital lobe(middle occipital gyrus), right insula, right parahippocampal gyrus, and left cingulate gyrus. The voxel sizes of atrophic gray matter positively correlated with fractional anisotropy values in white matter association fibers in the patient group. These findings suggest that white matter fiber bundles are extensively injured in multiple sclerosis patients. The main areas of gray matter atrophy in multiple sclerosis are the frontal lobe, parietal lobe, caudate nucleus, parahippocampal gyrus, and cingulate gyrus. Gray matter atrophy is strongly associated with white matter injury in multiple sclerosis patients, particularly with injury to association fibers.     

Differential impact of ApoE ε4 on cortical activation during famous face recognition in cognitively intact individuals and patients with amnestic mild cognitive impairment

This study explores the neurofunctional correlates of the recognition of famous faces in patients with amnestic mild cognitive impairment (aMCI) and healthy controls depending on the genetic risk factor, Apolipoprotein E (ApoE) ε4. An event-related functional magnetic resonance imaging experiment was conducted while participants discriminated between famous and nonfamous faces. We compared the results of 32 healthy controls [17 ApoE ε4 carriers (E4+); 15 noncarriers (E4-)] with those of 30 patients with aMCI (16 E4+; 14 E4-). Despite comparable task performance, patients with aMCI, E4+ showed significantly less activation in a large cortical network including the left parahippocampal gyrus than patients with aMCI E4-. Furthermore, in the aMCI group, we found significantly reduced activation in the left parahippocampal gyrus and posterior cingulate cortex compared with the control group. Our results show that critical regions of the brain show functional decline associated with major risk factors, such as ApoE ε4 allele and neuropsychological signs of aMCI for the development of Alzheimer disease. Importantly, the ApoE genotype seems to influence cortical activation in patients with aMCI and to a lesser degree in healthy controls as well, who are without any cognitive symptoms.