轻度认知功能障碍患者动态脑电图的定量分析

探讨轻度认知功能障碍患者动态脑电图的量化指标,为认知功能障碍早期诊断预防提供依据。选取30例轻度认知功能障碍患者和30例正常老年人作为病例组和对照组,进行MMSE测试和动态脑电图监测,比较两组观察对象α、β、和慢波功率。病例组和对照组的双侧顶枕α功率及大脑各位点的θ和δ功率差别有统计学意义（P＜0．05）。病例组及对照组在睡眠2期纺锤波的时限、频率及密度差别有统计学意义（P＜0．05））。脑电图α功率下降,θ和δ功率增加可以提示认知功能下降,睡眠2期纺锤波的时限、频率及密度可以作为认知功能水平脑电图测试的参考指标。     

综合性医院住院老年人认知功能的调查研究

分析综合性医院老年病人认知功能异常的检出率、特点及其影响因素。方法 :取 1997年 1月 15日上海甘泉医院住院病人 (年龄≥ 6 0岁 ) 16 4例。调查工具为中文版简易智能状态检查 (MMSE)。根据MMSE评分划分为正常组和异常组。结果 :①性别、教育程度对正常组与异常组MMSE均有影响 ;二组与教育程度密切有关 ,高文化程度对语言的短时记忆、物体命名有一定保护作用 ;但正常组随年龄增高 ,分数呈降低趋势 ,异常组MMSE总分、因子分则与年龄无相关 ;异常组受性别影响程度高于正常组 ,呈负相关。②认知功能异常检出率为 14 0 %。结论 :对 6 0岁以上住院病人进行常规认知功能筛选 ,以利早期诊断痴呆     

社区的老年人饮茶、认知与抑郁的关系

目的调查社区老年人饮茶、认知与抑郁之间的关系。方法采用一般资料调查表、简版老年抑郁量表以及简易精神状态量表对来自社区的324名老年人进行调查,对数据进行回归分析及中介效应检验。结果①是否饮用绿茶(t=-3.56,P0.01)、花茶(t=-2.17,P0.05)的老年人的抑郁得分存在显著性的差异;饮茶量的各个水平与抑郁之间都存在显著性的差异(t=-9.72~3.38,P0.01);认知因素与抑郁的差异达到显著性水平(t=-6.97,P0.01);②认知因素在饮茶与老年抑郁两个因素之间起部分中介效应(P0.05)。结论经常饮用绿茶或花茶可以预测老年人的抑郁情绪,饮用红茶或乌龙茶则不能预测老年人的抑郁情绪;饮茶可以通过提高老年人的认识水平,从而降低抑郁水平,还可以直接对老年抑郁产生预测作用,起到部分中介作用。     

老年性痴呆患者与正常老年人脑电图对照研究

目的:了解老年性痴呆患者的脑电图的特点。方法:选老年性痴呆(AD)患者46例,正常老年人48例进行脑电图(EEG)检查。结果:AD组EEG异常率86.96%,对照组EEG异常率39.58%,AD患者EEG的异常率明显高于对照组(P<0.005),AD患者EEG异常和痴呆严重程度有关。结论:EEG检查可作为AD的常规临床评价指标之一,特别在AD患者中能及时反映脑功能损害程度,对掌握病情进展和判断预后有着重要作用。     

老年人人格特征与认知功能

目的：了解老年人人格特征与认知功能的关系。方法：采用整群随机抽样的方法调查山西省太原市两个社区的老人109人，进行算术、数字广度、填图、木块图、数字符号、情节记忆、短时视觉记忆、空间推理8项认知功能测验．应用卡氏16项人格因素测验进行人格特征的测查。结果：所调查的老年群体的人格特征主要表现为“谦逊顺从”和“沉着自信”。各人格因素中，聪慧、有恒对算术、幻想对数字广度、聪慧对木块图、恃强对数字符号、敏感对空间推理、忧虑、实验对短期视觉记忆的影响具有统计学显著性。结论：年龄是影响老年人认知水平的主要因素。高的受教育水平对认知下降有保护作用。不同的人格因素影响不同的认知功能，人格特征与认知功能的互动作用可能为老年人认知功能下降的干预提供重要线索．     

老年人甲状腺功能异常与认知功能损害的关系

本文综述了老年人甲状腺功能异常与认知功能损害的关系,进而对临床工作人员进行指导,防止误诊。分别从行为学、动物实验、神经影像学和神经电生理等方面探讨甲状腺功能对认知功能的影响。     

认知负载状态下的精神分裂症患者脑电图特异性研究

认知功能损害是精神分裂症的三大原发症状之一,在疾病早期发现和高危人群风险预警等方面具有重要价值。为了研究精神分裂症患者在认知负载状态下的脑电图特异性,本试验收集17例精神分裂症患者和19例健康受试者的脑电信号作为对照,基于小波变换提取各频段信号,计算非线性动力学及脑功能网络属性等特征,并利用机器学习算法将两类人群进行自动分类分析。试验结果表明,两组受试者在认知负载状态下,Fp1和Fp2导联在α、β、θ、γ这4个频带的关联维数和样本熵的差异均具有统计学意义,提示大脑额叶功能损伤是精神分裂症认知功能损害的重要原因。进一步基于机器学习的自动分类分析结果表明,将非线性动力学与脑功能网络属性相结合作为分类器的输入特征,所得分类效果最优,其结果显示准确率为76.77%、敏感度为72.09%、特异性为80.36%。本研究结果表明,脑电信号的非线性动力学和脑功能网络属性等特征,或可作为精神分裂症早期筛查和辅助诊断的潜在生物标记物。     

临床下痫样放电与认知功能受损关系分析

目的：分析癫痫临床下痫样放电与认识功能受损的关系。方法：分析1998年8月至2002年3月，用MB8000型8导动态脑电图监测到的8例临床下痫样放电。结果：男6例，女2例。8例均有痫样放电，临床均伴有不同程度的认识功能受损表现。结论：临床下痫样放电与认识功能受损有密切关系。所以对无明显临床发作学习困难患儿作动态脑电图检查是很有必要的。     

老年人脑血管病的脑电图分析

目的:了解老年人脑血管病的脑电图特点,为早期诊治老年人脑血管病提供有价值的科学依据。方法:总结本院2003年1月至2005年1月,经临床确诊的95例老年人脑血管病的临床及脑电图。结果:脑电图正常24例(25.3%),异常71例(74.7%)。其中,轻度异常18例,占异常的39.4%,中度异常以上7例(9.9%),局灶性异常36例,占异常脑电图的50.7%。结论:老年人脑血管病的脑电图变化与病因的种类、程度、病程、脑电图检查的时间及检查时有无意识障碍及障碍的程度等有密切的关系。脑电图的动态观察对老年人脑血管病的诊断、鉴别诊断及判断预后均有指导意义。     

癫痫患者认知功能与临床电生理评价

癫痫是神经科常见病,我国约有,900万以上的癫痫患者,其中30％～40%存在认知障碍。认知功能障碍主要表现在学习记忆力、注意力、语言能力、判断力及社会行为等功能受损。其严重影响了患者的生活质量,并给家庭和社会带来了巨大的经济负担。     

Resting EEG theta power correlates with cognitive performance in healthy older adults

We address the degree to which resting EEG bandpower is associated with cognitive performance in 73 healthy older adults (aged 56-70). Relative theta (4-6.5 Hz) power was significantly correlated with immediate and delayed verbal recall, attention, and executive function measures. Relative delta and alpha power and peak alpha frequency did not correlate with any cognitive measures. These data indicate that high resting theta power in healthy older adults is associated with better cognitive function and may be a marker of healthy neurocognitive aging. Comparison of these with previous findings suggests that two forms of theta-frequency oscillations may exist; one indicative of healthy neurocognitive function and the other, EEG/alpha slowing linked to (future) substantial cognitive decline. Future EEG investigations of cognitive aging or decline should analyze both relative theta power and degree of EEG/alpha slowing so as not to confound these.     

The reflection of cognitive tasks in EEG and MRI and a method of its visualization

Summary Up until recently, neurology was dominated by localisatory thinking. Language and other so-calledcenters were considered to be centers of command controlling the respective functions. Today, there is general agreement that, instead, for every brain function numerous brain regions must act together. For the exploration of these manifold topographic cooperations produced by cognitive tasks, coherence of long-term EEG periods proved to be a proficient parameter for the representation of functionally essential connections. Because of the unequivocal meaningfulness of absolute coherence values, instead, only the signs of significant differences between coherence values during cognitive tasks and periods of EEG at rest before and after the task were considered for all possible electrode pairings and charted on schematic maps of the brain. In addition, the signs of significant changes of amplitude were entered. This procedure was performed for each of 6 frequency bands and for the 19 electrodes of the 10/20 system, thus yielding 171 possible plus or minus values for coherence and 19 for amplitude, respectively. The positions of the electrodes were marked by an MRI contrast medium. After the EEG, MRI examination was performed. The MRI data were segmented and the cortex was mapped onto a plane using a method similar to cartography. The exact electrode positions are registered from a similarly obtained map of the scalp and the electrode position pattern is used as basis for the coherence graphs. A detailed map of the cortex based on the segmented MRI data with the electrode positions marked is provided as a reference enabling allocation of the electrodes to the cortical structures. The usefulness of this procedure is demonstrated with a single subject by means of different cognitive tasks including musical thinking.This work was supported by the Austrian Fonds zur Förderung der wissenschaftlichen Forschung, Project Nr. 4909. The authors wish to thank Mrs. Susan Etlinger, Ph.D., for linguistic advice and Mrs. Anni Schneider for experimental assistance. Prof. Dr. H. Imhof has to be thanked for the performance of the MRI.     

多导体视诱发脑电采集系统设计及视差深度诱发电位研究

我们根据科研实验要求利用现有的微机系统和临床脑电图仪建立了一套适用脑认知科学研究的多导视觉诱发脑电（VEP）信号采集处理系统。该系统既能满足部分临床应用的需要,同时也能根据实验要求,进行立体视觉认知过程脑电（EEG）的信息提取和分析处理。通过立体视觉深度相关脑诱发电位提取及比较分析,对深度相关的特征视觉诱发电位发放进行了标定。实验系统的建立为我们深入研究立体视觉相关脑功能和体视认知过程提供了有力的手段。     

RAGE阻断剂FPS-ZM1减轻异氟醚麻醉诱发老龄大鼠认知功能障碍

目的探讨RAGE阻断剂FPS-ZM1对异氟醚麻醉诱发老龄大鼠认知功能障碍的影响。方法将老龄大鼠60只,随机分为4组(n=15):NS+O2组、NS+ISO组、FPS-ZM1+ISO组及FPS-ZM1+O2组。NS+O2组及NS+ISO组,侧脑室注射无菌0.9%氯化钠溶液10μL,FPS-ZM1+ISO及FPS-ZM1+O2组,侧脑室注射FPS-ZM1 10μL(5 g/L)。侧脑室注射后24 h,NS+O2及FPS-ZM1+O2组吸入含有30%氧气的空氧混合气体4 h,FPS-ZM1+ISO及FPS-ZM1+ISO组吸入2%异氟醚+100%氧气4 h。用Morris水迷宫评测大鼠学习和记忆功能,用免疫组织化学技术观察海马CA1区RAGE及Aβ的表达。结果与NS+O2组相比,NS+ISO组第1~4天逃避潜伏期延长、探索时间缩短、海马CA1区RAGE表达上调、Aβ表达上调。与NS+ISO组相比,FPS-ZM1+ISO组第1~4天逃避潜伏期缩短,探索时间延长,RAGE表达下调、Aβ表达下调。结论 RAGE阻断剂FPS-ZM1可改善异氟醚麻醉诱发老年大鼠认知功能障碍,其机制可能与其抑制海马CA1区Aβ沉积有关。     

A negative association between video game experience and proactive cognitive control

Some evidence demonstrates that video game experience has a beneficial effect on visuospatial cognition. In contrast, other evidence indicates that video game experience may be negatively related to cognitive control. In this study we examined the specificity of the influence of video game experience on cognitive control. Participants with high and low video game experience performed the Stroop task while event-related brain potentials were recorded. The behavioral data revealed no difference between high and low gamers for the Stroop interference effect and a reduction in the conflict adaptation effect in high gamers. The amplitude of the medial frontal negativity and a frontal slow wave was attenuated in high gamers, and there was no effect of gaming status on the conflict slow potential. These data lead to the suggestion that video game experience has a negative influence on proactive, but not reactive, cognitive control.     

On the relationship between occipital cortex activity and inhibition of return

The present study explored the relationship between inhibition of return (IOR) and visual processes by seeking evidence that IOR and changes in event-related potential (ERP) indices of occipital cortex activity covary in response to experimental manipulation. The presence or absence of a central reorienting event was manipulated within the context of a cue–target experiment. When a reorienting event was presented in the interval between cue and target, IOR was accompanied by reductions in the amplitudes of early occipital ERP peaks on validly cued trials relative to invalidly cued trials. When a reorienting event was not presented, neither IOR nor modulations of the occipital ERP peaks was observed. These results provide strong evidence that IOR arises from changes in occipital visual processing. We propose that IOR arises from a slowing of response-selection processes on validly cued trials due differences in the perceptual input to the decision-making process.     

Relationship between EEG power and rhythm synchronization in health and cognitive pathology

We report here studies of comparative measures of spectral density and cortical interactions in EEG rhythms in health and schizophrenia. In healthy subjects, all rhythms were symmetrical and synchronous. In “acute” schizophrenia, unlike the situation in health, there was asymmetry (predominantly right-sided) in the distribution of the spectral power of EEG rhythms. In chronic patients, asymmetry was less marked, though the power of most EEG rhythms was significantly lower than in the other two study groups. “Acute” patients showed a lack of interhemisphere interactions for all rhythms apart from the alpha rhythm, while the number of cortical interactions in chronic patients was rather lower than that in the “acute” patients, though there were significantly fewer than in healthy subjects. In addition, the gamma range showed only one interhemisphere association in the posterior areas. These neurophysiological characteristics may underlie a number of the impairments of mental activity in patients with schizophrenia. These data may also indicate that the linkage between power characteristics and synchronization of EEG rhythms is a necessary condition for normal perceptive and cognitive activity and the organization of behavior. __________ Translated from Zhurnal Vysshei Nervnoi Deyatel’nosti imeni I. P. Pavlova, Vol. 55, No. 4, pp. 496–504, July–August, 2005.     

Associations between quantitative sleep EEG and subsequent cognitive decline in older women

The pathophysiological processes of Alzheimer's dementia predate its clinical manifestation. Sleep disturbances can accelerate the aging process and are common features of dementia. This study examined whether quantitative sleep electroencephalogram changes predate the clinical development of mild cognitive impairment and/or incident dementia. We collected data from a nested case‐control sample of women (mean age 83 years) from the Sleep and Cognition Study, an ancillary study to the longitudinal Study of Osteoporotic Fractures, who were characterized as cognitively normal at the time of a baseline polysomnography study (Study of Osteoporotic Fractures visit 8) based on a Mini‐Mental Status Exam (MMSE) score >24. Cases (n = 85) were women who developed new mild cognitive impairment or dementia by objective cognitive testing 5 years after polysomnography. Controls were women with no mild cognitive impairment/dementia (n = 85) at baseline or at follow‐up. Differences in electroencephalogram absolute and relative power density were observed between the two groups. Specifically, higher electroencephalogram power values were found in the dementia/mild cognitive impairment group, for the alpha (p = .01) and theta bands (p = .04) in non‐rapid eye movement sleep, as well as alpha (p = .04) and sigma (p = .04) bands in rapid eye movement sleep. In contrast, there were no group differences in traditional polysomnography measures of sleep architecture and sleep stage distribution, as well as sleep apnea and periodic limb movement indices. Our results provide evidence for quantitative electroencephalogram changes, which precede the clinical onset of cognitive decline and the diagnosis of dementia in elderly women, and support the application of quantitative sleep electroencephalogram analysis as a promising biomarker for imminent cognitive decline.     

Association study of brain-derived neurotrophic factor and apolipoprotein E polymorphisms and cognitive function in aged males without dementia

Genetic factors for inter-individual variation in cognition have been arousing great interest among researchers. Among the many associated genes, brain-derived neurotrophic factor (BDNF) and apolipoprotein E (APOE), as two of the most frequently studied, might be good prospects for cognitive genetics. Thus, the aim of this study was to investigate both the isolated and cooperative effect of BDNF and APOE on normal cognitive ageing. A homogeneous population of Chinese aged males (N = 161) were genotyped for functional genetic variants of BDNF (BDNF-G196A) and APOE (APOE-?4) and assessed by a comprehensive neuropsychological measurement (Cognitive Abilities Screening Instrument Chinese version; CASI C-2.0). Thereafter genotypic group differences of BDNF and APOE in CASI cognitive profiles were tested. Results from the present study suggest the possible influence of APOE on specific cognitive domains (CASI orientation and language domains; p = 0.010 and 0.028, respectively), whereas there was no significant role of BDNF, either solely or with APOE, in cognition in the elderly. Our findings suggest a possible association between APOE-?4 and specific cognitive domains in the aged male, whereas the functional genetic variant of BDNF (BDNF-G196A) played no significant role in normal cognitive ageing.     

Lateral Specialization of Cognitive Mode: An EEG Study

We have studied EEG asymmetry in normal subjects during verbal and spatial tasks. Recordings were made from the left and right temporal and parietal areas, and the ratios of average power (1–35 Hz) in homologous leads T₄/T₃ and P₄/P₃ were computed. This ratio (right over left) was greater in the verbal tasks than in the spatial tasks. With this measure we have been able to distinguish between these two cognitive modes as they occur in normal subjects, using simple scalp recording.