长期海洛因成瘾者前额叶功能连接的静息态fMRI研究

目的 利用静息态fMRI探讨长期海洛因成瘾者前额叶功能连接的变化情况.方法 13例长期海洛因成瘾者和14例正常者接受静息态fMRI检查,对数据进行相关的预处理后,以前额叶为种子点与全脑每个体素进行相关分析,比较海洛因成瘾组与正常对照组前额叶功能连接的变化情况.结果 以左侧前额叶为种子点进行功能连接分析,海洛因成瘾组左侧前额叶与左侧海马、右侧前扣带回、左侧额中回、右侧额中回、右侧楔前叶功能连接明显低于正常对照组:以右侧前额叶为种子点进行功能连接分析,海洛因成瘾组右侧前额叶与左侧眶额叶、左侧额中回功能连接明显低于正常对照组.结论 长期海洛因成瘾者前额叶与相关脑区的功能连接减弱,前额叶可能参与了海洛因成瘾的维持与戒断后复吸.

Abstract：

Objective To explore the changes of functional connectivity of the prefrontal cortex in chronic heroin addicts under resting-state functional MRI (fMRI). Methods Resting fMRI examination was performed on 13 chronic heroin addicts and 14 healthy volunteers. After pre-processing the resting-state fMRI data, the prefrontal cortex was selected as the seed region, with which a whole-brain voxel temporal correlation in Iow frequency fMRI fluctuations was analyzed and the changes of functional connectivity of the prefrontal lobe in both chronic heroin addicts and healthy volunteers were calculated with SPM5 software. Results Compared with that in the control group, the functional connectivity between the left prefrontal cortex and the left hippocampus, right anterior cingulate, left middle frontal gyrus, right middle frontal gyrus, right precuneus in the heroin addiction group was significantly decreased. The functional connectivity between the right prefrontal cortex and the left orbital frontal cortex, left middle frontal gyrus in thc heroin addiction group was also significantly decreased as compared with that in the control group. Conclusion Functional connectivity of prefrontal cortex in chronic heroin addicts decreases, indicating that the prefrontal cortex may be involved in the maintenance of heroin addiction and relapse after withdrawal.     

网络游戏成瘾者前扣带回功能连接静息态fMRI研究

目的 探讨青少年网络游戏成瘾者静息态下前扣带回功能连接的变化情况,从功能连接的角度解释前扣带回在网络游戏成瘾中的作用.方法 选择自2011年3月至10月在安徽医科大学附属省立医院心理门诊就诊的网络成瘾者17例为成瘾组,同期招募17例健康志愿者为正常对照组.对34例被试者一般情况进行了解并比较两组之间差异;成瘾组和正常对照组分别进行静息态fMRI扫描,数据采集后进行预处理,分别以左、右前扣带回为感兴趣脑区与全脑进行功能连接分析,比较成瘾组和正常对照组前扣带回功能连接的变化情况.结果 成瘾组每日或每周平均网络游戏时间及网络游戏渴求程度明显高于正常对照组,差异有统计学意义(P＜0.05);在静息态下,正常对照组与网络成瘾组的前扣带回都与前额叶、中后扣带回、伏核、中脑、颞叶及枕叶等脑区存在功能连接关系,与全脑其他脑区比较差异(体素差异)有统计学意义(P＜0.05);但与正常对照组比较,在静息态下成瘾组前扣带回与中脑、扣带回皮层、伏核及辅助运动区功能连接增强,与双侧前额叶、颞叶及枕叶功能连接减弱(P＜0.05).结论 网络游戏成瘾者前扣带回功能连接存在异常并可能与网络游戏成瘾的产生和维持有关.     

网络游戏成瘾者伏核功能连接静息态fMRI的研究

目的 利用静息态功能磁共振(fMRI)分析网络游戏成瘾者与伏核存在功能连接的脑区,了解伏核功能异常在网络游戏成瘾发病机制中的作用.方法 网络游戏成瘾者和健康对照组各17例,扫描前上网玩耍自己喜欢的网络游戏,60 min后突然中止网络使用,对被试的网络游戏渴求程度进行心理学测评;休息30 min后进行静息态fMRI扫描,分别选取左、右侧伏核为感兴趣区进行脑功能连接分析,确定与双侧伏核有功能连接的脑区,并将激活程度与网络游戏渴求程度进行相关分析.结果 网络游戏成瘾青少年对网络游戏内容的渴望程度、喜欢程度、再次上网的渴望程度明显高于健康对照组(P＜0.05);网络游戏成瘾组的伏核与前扣带回、中脑、海马功能连接明显高于健康对照组,而与前额叶、颞叶及枕叶功能连接明显低于健康对照组(P＜0.05);网络游戏成瘾者伏核与前额叶、前扣带回、中脑及海马的功能连接程度和网络游戏渴求程度存在相关性(r=0.70、0.76、0.65、0.79,P＜0.05).结论 网络游戏成瘾者伏核功能异常,提示伏核是网络游戏成瘾“奖赏系统”的重要组成部分,伏核功能异常可能参与了网络游戏成瘾的产生与维持.     

以妄想为主的男性精神分裂症患者内侧前额叶功能连接的静息态磁共振成像研究

目的:利用静息态功能性磁共振成像(fMRI)技术,观察以妄想为主的男性精神分裂症患者内侧前额叶(MPFC)的功能连接. 方法:对17例以妄想为主的男性精神分裂症患者(患者组)和17例年龄、利手、性别、受教育程度与患者组均匹配的健康者(对照组)进行静息态fMRI扫描.通过分析MPFC与大脑其他区域的低频fMRI信号波动的相关性,观察MPFC的功能连接.将患者组和对照组在静息状态下MPFC的脑功能连接活动进行相关分析,设P＜0.005且体素范围(K值)≥12为相关具有显著差异. 结果:与对照组相比,患者组MPFC与右颞上回、右额上回及双侧额中回、右海马、右杏仁核、眶额叶、右海马旁回的功能连接减低;与左枕叶中部、左顶下小叶及左小脑前叶的功能连接增强.结论:静息态下以妄想为主的男性精神分裂症患者MPFC与默认网络其他结构的功能连接存在异常.     

海洛因依赖者认知功能损害的对照研究

目的　采用威斯康星 (Wisconsin)卡片分类测验评估海洛因依赖者与正常人群的认知差异。方法　对完成脱瘾治疗的 4 8例海洛因依赖者和 4 2例正常人进行Wisconsin卡片分类测验评定。结果　两组间总应答数、完成分类数、正确应答百分数、错误应答数、持续应答数、持续性错误数、概念化应答百分数和完成第一类所需应答数的比较显示 ,海洛因依赖组较正常人组差 (P <0 0 1)。相关因素分析显示 ,吸毒时间及日吸毒量与认知功能损害程度呈正相关 (r分别为 0 4 1～ 0 4 7和 0 35～ 0 4 2 ;P <0 0 5 )。结论　海洛因依赖者存在认知功能损害     

多巴胺受体与前额叶皮层的认知功能

前额叶皮层是指额叶中央前回和中央旁小叶以前的广大皮层 ,既包括半球的背外侧面 ,又包括其内侧面和眶面 ,具有丰富的皮层间和皮层下交互纤维联系。前额叶在人的注意力、排除干扰能力、思维、逻辑推理、行为计划、组织、工作记忆等脑高级认知功能中起重要作用。前额叶皮层功能紊乱与许多精神症状有关 ,如 :精神分裂症、注意缺陷多动障碍等 [1～ 3 ] 。目前大量研究都支持精神分裂症的认知功能障碍与前额叶多巴胺 (DA)的异常有关。研究表明 :中脑大脑皮层 (额叶、扣带回 ) DA系统主要参与认知功能。本文综述了近年来 DA受体与前额叶皮层认…     

抑郁症患者眶额叶皮层功能连接偏离的研究

目的 通过功能磁共振成像技术,研究抑郁症患者和健康对照组在情感处理时眶额叶皮层的功能连接偏离,为抑郁症的早期诊断和疗效评估提供影像学依据.方法 对25例重度抑郁症患者和15名健康对照组在执行面貌一致性任务时进行功能性磁共振成像.结果 和健康对照组相比重度抑郁症患者的背侧前扣带回皮层、楔前叶、小脑与眶额叶的活动连接减少;抑郁症患者的眶额叶皮层和背外侧前额叶皮层、右额叶岛盖部、左运动区之间的功能连接比健康对照组有所增加.结论 眶额叶皮层在抑郁症的病理生理学机制中发挥着关键作用.眶额叶皮层连接的失衡似乎代表加工偏离的神经机制.从神经生物学的角度来看,楔前叶和扣带回的连接解离活动与眶额叶皮层的自我架构规则的问题相关,而背外侧前额叶皮层到眶额叶的连接增加可能代表更高消极刺激的神经反应.     

戒断期海洛因依赖者额叶认知功能的功能磁共振成像研究

目的 研究戒断期海洛因依赖者(AHD)的脑认知功能.方法 采用3.0 T磁共振成像系统,对30例AHD(AHD组)和18名健康对照者(对照组)在完成Go/NoGo任务时行全脑功能磁共振成像(fMRI)扫描,记录反应时间(RT).结果 (1)RT:AHD组在完成Go/NoGo任务时的RT[(394±34)ms]长于对照组[(374±26)ms;P<0.05].(2)fMRI:对照组在完成Go/NoGo任务时,诱发激活双侧前额叶内侧回、前扣带回以及双侧额下回等脑区;AHD组全脑活动普遍低,仅有双侧额上回和左侧额中回激活.两组间比较,AHD组激活显著低于对照组的区域主要位于在双侧额内侧回、前扣带回、额下回及双侧颞叶等脑区(P<0.005).结论 戒断期海洛因依赖者反应抑制功能障碍仍然存在,促进其认知功能的恢复可能成为戒毒、抗复吸的有效策略.     

线索诱发海洛因依赖者戒断期心理渴求的功能磁共振成像研究

目的　探讨线索诱发海洛因依赖者戒断期心理渴求的特异神经结构,为寻找干预复吸的有效策略提供理论依据。方法　采用3 0T磁共振成像系统,对30例戒断期海洛因依赖者和17名健康对照者在观看自然风光和吸毒图片时行全脑扫描,识别线索诱发海洛因渴求的特异脑区。结果(1)与观看自然风光相比,观看吸毒图片可以诱导戒断期海洛因依赖者产生明显心理渴求(t=-6 535,P<0 001),且渴求程度与吸毒量呈正相关(r=0 464,P=0 01)。(2)共发现17个参与线索诱发海洛因渴求的特异脑区,主要集中在前额叶皮质和边缘系统,以左侧为主。自我报告渴求与激活脑区数目及左侧额下回、额中回、扣带回前部、额内测回,右侧眶额皮质、杏仁核和岛叶等7个脑区的激活体积呈正相关(P<0 05)。结论　多个脑区参与线索诱发海洛因渴求,既包括认知过程又涉及情感加工,不同渴求程度激活脑区数目与某些脑区的激活体积不同。     

海洛因依赖者认知功能障碍的WCST对照研究

目的 采用威斯康星卡片分类测验(Wisconsin Card Sorting Test, WCST)分析海洛因依赖者认知功能损害情况.方法 分别对60例住院脱毒治疗的海洛因依赖者与40例正常对照者进行WCST测验.结果 与正常对照相比,海洛因依赖组WCST的总应答数(100.6±20.2)、完成分类数(5.4±1.4)、概念化水平百分数(87.9±13.0)%等测验值均较正常组差(海洛因依赖组60例,正常对照组40例,P<0.05);男女海洛因依赖者WCST测验结果无显著差异;相关性分析发现海洛因依赖者年龄、受教育年限、用毒品年限、每日使用量与WCST测验结果之间没有显著相关性.结论 海洛因依赖者存在认知功能损害,应对海洛因依赖者进行系统的康复治疗改善其认知功能预防复发.     

Altered gray matter volume and disrupted functional connectivity of dorsolateral prefrontal cortex in men with heroin dependence

Aim

Chronic heroin use can cause various neuropathological characteristics that may compromise brain function. The present study evaluated the alteration of gray matter volume (GMV) and its resting‐state functional connectivity (rsFC) over the dorsolateral prefrontal cortex (DLPFC) among male heroin users.

Methods

Thirty heroin‐dependent men undergoing methadone maintenance therapy and 30 educational‐level‐ and age‐matched male controls were recruited for this study. To assess their GMV and rsFC, the participants were evaluated using spoiled gradient echo and gradient‐recalled echo planar imaging sequences with a 3‐Tesla General Electric MR scanner under resting state.

Results

The heroin‐dependent men showed lower GMV over the right DLPFC in comparison with the controls. Further evaluation of the rsFC of the right DLPFC revealed a marked decrease in interhemispheric DLPFC connectivity among those with heroin dependence under control of head movement and GMV of the right DLPFC.

Conclusion

Although the mechanism remains unclear, the present study shows that chronic heroin use is associated with alteration of morphology as well as rsFC over the right DLPFC. As the DLPFC plays an imperative role in various domains of cognitive function, service providers for heroin users should consider the impacts of possible DLPFC‐related cognitive deficits on treatment effectiveness.

     

Sex differences in the behavioral inhibition system and ventromedial prefrontal cortex connectivity

The reinforcement sensitivity theory proposes brain–behavioral systems that underlie individual differences in sensitivity to punishment and reward. Such trait sensitivity is assessed using the behavioral inhibition/activation system (BIS/BAS) scales. Recent studies have reported sex-linked neuroanatomical correlates of the BIS/BAS, especially in the regions belonging to the valuation and salience networks that are associated with the representation of subjective value (SV), whereas less effort has been focused on investigating the neurofunctional aspects associated with sex differences in the BIS/BAS. We tested whether functional connectivity (FC) of the regions associated with the representation of SV mediates the relationship between sex and BIS sensitivity in healthy young adults by using resting-state functional magnetic resonance imaging data and self-reported BIS/BAS measures. Compared with males, females had heightened BIS sensitivity and increased FC between the ventromedial prefrontal cortex (vmPFC) seed and posterior parietal areas; this FC mediated the impact of sex on BIS sensitivity. Given that the observed vmPFC FC maps are considered part of the default-mode network, which is involved in ruminative processes, and that the BIS is associated with rumination and negative affect, our results may have implications for psychiatric disorders such as depression and anxiety, both of which have high incidence in females.     

Regional brain activation changes and abnormal functional connectivity of the ventrolateral prefrontal cortex during working memory processing in adults with attention‐deficit/hyperactivity disorder

Previous studies on working memory (WM) function in adults with attention‐deficit/hyperactivity disorder (ADHD) suggested aberrant activation of the prefrontal cortex and the cerebellum. Although it has been hypothesized that activation differences in these regions most likely reflect aberrant frontocerebellar circuits, the functional coupling of these brain networks during cognitive performance has not been investigated so far. In this study, functional magnetic resonance imaging (fMRI) and both univariate and multivariate analytic techniques were used to investigate regional activation changes and functional connectivity differences during cognitive processing in healthy controls (n = 12) and ADHD adults (n = 12). Behavioral performance during a parametric verbal WM paradigm did not significantly differ between adults with ADHD and healthy controls. During the delay period of the activation task, however, ADHD patients showed significantly less activation in the left ventrolateral prefrontal cortex (VLPFC), as well as in cerebellar and occipital regions compared with healthy control subjects. In both groups, independent component analyses revealed a functional network comprising bilateral lateral prefrontal, striatal, and cingulate regions. ADHD adults had significantly lower connectivity in the bilateral VLPFC, the anterior cingulate cortex, the superior parietal lobule, and the cerebellum compared with healthy controls. Increased connectivity in ADHD adults was found in right prefrontal regions, the left dorsal cingulate cortex and the left cuneus. These findings suggest both regional brain activation deficits and functional connectivity changes of the VLPFC and the cerebellum as well as functional connectivity abnormalities of the anterior cingulate and the parietal cortex in ADHD adults during WM processing. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.     

海洛因成瘾者扣带前回结构与功能连接的MRI研究

目的 利用基于体素的形态学分析(voxel-based morphometry,VBM)和静息态fMRI探讨扣带前回结构和功能连接的改变,分析扣带前回在海洛因成瘾中的作用.方法 15例海洛因成瘾者和15例正常人分别作为成瘾组和正常对照组,均接受3D结构像和静息态fMRI检查,使用VBM比较2组受试者大脑的结构差异;以扣...     

难治性癫痫患者楔前叶功能连接的静息态功能磁共振成像研究

目的应用静息态功能磁共振成像(rs-f MRI)探讨难治性癫痫患者楔前叶与全脑功能连接的改变及其意义。方法对23例难治性癫痫患者(癫痫组)及23名健康人(对照组)进行rs-f MRI检查,采集数据后采用功能连接的方法,分别计算以左侧楔前叶和右侧楔前叶为感兴趣区与全脑的功能连接,运用双样本t检验的统计学方法发现两组的显著性差异并进行分析。结果癫痫组左侧楔前叶与双侧顶下小叶、双侧岛叶、右侧缘上回、右侧额中回和双侧额下回的功能连接较对照组减弱(均P0.05);癫痫组左侧楔前叶与双侧海马旁回、双侧额上回、左侧后扣带回的功能连接较对照组增强(均P0.05)。癫痫组右侧楔前叶与左侧顶下小叶、右侧缘上回、右侧额中回、右侧额下回的功能连接较对照组减弱(均P0.05);癫痫组右侧楔前叶与双侧楔叶、左侧后扣带回的功能连接较对照组增强(均P0.05)。结论难治性癫痫患者静息状态下楔前叶与全脑的功能连接存在异常,"默认网络"功能的抑制可能是癫痫患者意识及认知等功能损害的重要原因。     

Dynamic frontostriatal functional peak connectivity (in alcohol use disorder)

Alcohol use disorder (AUD) is associated with changes in frontostriatal connectivity, but functional magnetic resonance imaging (fMRI) functional connectivity (FC) approaches are usually not adapted to these circuits. We developed a circuit‐specific fMRI analysis approach to detect dynamic changes in frontostriatal FC inspired by medial‐ventral‐rostral to lateral‐dorsal‐caudal frontostriatal gradients originally identified in nonhuman primate tract‐tracing data. In our PeaCoG (“ pea k co nnectivity on a g radient”) approach we use information about the location of strongest FC on empirical frontostriatal connectivity gradients. We have recently described a basic PeaCoG version with conventional FC, and now developed a dynamic PeaCoG approach with sliding‐window FC. In resting state data of n = 66 AUD participants and n = 40 healthy controls we continue here the analyses that we began with the basic version. Our former result of an AUD‐associated ventral shift in right orbitofrontal cortex PeaCoG is consistently detected in the dynamic approach. Temporospatial variability of dynamic PeaCoG in the left dorsolateral prefrontal cortex is reduced in AUD and associated with self‐efficacy to abstain and days of abstinence. Our method has the potential to provide insight into the dynamics of frontostriatal circuits, which has so far been relatively unexplored, and into their role in mental disorders and normal cognition.     

Abnormal prefrontal cortex function during response inhibition in Turner syndrome: functional magnetic resonance imaging evidence.

BACKGROUND: Turner syndrome (TuS) arises from the partial or complete absence of one X chromosome. Although neuropsychological studies report impaired attentional function and response inhibition in TuS, the neural correlates of these cognitive problems are unknown. METHODS: Eleven female subjects with TuS and 11 individually matched normal control subjects were imaged using functional magnetic resonance imaging while performing a Go/NoGo task. RESULTS: Groups did not differ on accuracy or reaction time; however, the TuS group activated more in the bilateral superior and middle frontal gyri than control subjects. Control subjects did not activate more than the TuS group in any region. CONCLUSION: These findings suggest that female subjects with TuS compensate for executive dysfunction via recruitment of additional prefrontal cortex regions involved in inhibition, attention, and working memory, functions necessary for successful performance of Go/NoGo tasks. Elucidating brain function in TuS will advance our understanding of the influence of X-chromosome genes on neurodevelopment and brain function and contribute to planning future intervention strategies.