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91.
颞叶癫痫的临床特点与脑电图分析 总被引:1,自引:0,他引:1
王建茹 《现代电生理学杂志》2003,10(2):65-66
目的:分析颞叶癫痫患的临床特点及脑电图定位的意义。方法:回顾分析92例颞叶癫痫患的脑电图。结果:左颞有癫痫样波42例,右颞有癫痫样波29例,双颞有癫痫样波21例,临床表现与癫痫样波发放部位有关,癫痫波的传导主要有容积传导和神经传导方式。结论:结合患临床表现与脑电图癫痫样波起始部位分析有助于致痫灶的定位。 相似文献
92.
93.
J. Siegel C. R. Morton J. Sandkühler H. -M. Xiao M. Zimmermann 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1986,62(2):363-372
Summary In cats anaesthetized with sodium pentobarbital and 70% N2O, single lumbar dorsal horn neurons were excited by controlled noxious radiant heating of glabrous hindpaw skin. The EEG was recorded from the pericruciate cortex and posterior lateral gyrus. Subcortical forebrain sites where electrical stimulation inhibited dorsal horn neuronal heat-evoked responses contralaterally were identified by mapping the caudate nucleus, internal capsule, septum, nucleus accumbens and basal forebrain regions. Inhibitory sites were mainly located in the ventral forebrain (ventral septum, diagonal band, basal forebrain). The caudate nucleus and internal capsule had a low incidence and effectiveness of inhibitory sites. In the basal forebrain, the incidence and effectiveness of inhibitory sites decreased from caudal to rostral regions. There was a rostral limit of inhibitory sites, both medially and laterally. The magnitude of inhibition increased with graded increases in brain stimulation intensity. The mean incremental increase in inhibition was greater for caudal than for rostral basal forebrain sites. Mean stimulus currents for threshold of inhibition and for inhibition to 50% of control heat responses were lower for caudal than for rostral sites. Responses of the dorsal horn neurons to increasing temperatures of noxious skin heating were monotonic linear functions over the temperature range studied (48–53° C). Stimulation in both rostral and caudal basal forebrain decreased the slope of this stimulus-response function, with a greater decrease for caudal sites. Cortical EEG synchronization was evoked by stimulation in the caudate nucleus and rostral basal forebrain. For both regions, most synchronogenic sites did not produce descending inhibition of dorsal horn neurons. The significance of these findings in relation to descending inhibition from other brain regions and stimulation-produced analgesia is discussed. 相似文献
94.
儿童及青少年中央颞区放电的临床分析 总被引:4,自引:0,他引:4
目的:探讨儿童及青少年中央颞区癎样放电的特征和临床意义。方法:回顾分析近9年在同步录像脑电图(VEEG)或动态脑电图(AEEG)监测中具有中央颞区癎样放电的儿童和青少年的临床表现及与神经影像学异常的关系。结果:具有中央颞区癎样放电的儿童和青少年共452例,占同期接受EEG监测儿童及青少年的9.5%,占EEG各种癫癎样异常的15.4%。监测到中央颞区放电的平均年龄为7.28±3.15岁(1-17岁)。临床诊断包括伴中央颞区棘波的儿童良性癫癎(BECT)179例(39.6%),症状性或隐源性癫癎154例(34.1%),热性惊厥21例(4.7%),从无癫癎发作98例(21.7%)。在354例有癫癎发作者中235例(66%)为部分运动性发作,102例(28.7%)为全身强直阵挛发作;其他发作类型包括不典型失神发作9例(2.5%),肌阵挛发作6例(1.7%),负性肌阵挛发作4例(1.1%),痉挛发作3例(0.8%)。少数患者有一种以上发作形式。在283例有神经影像学记录的患者中,50例(17.7%)异常,其中仅10例异常部位与放电部位基本一致。结论:儿童及青少年中央颞区放电具有以下特点:①明显的年龄依赖性;②病因具有高度异源性,包括特发性、隐源性和症状性病因;③各种病因的中央颞区癎样放电均有一部分不伴有临床发作;④仅根据发作类型和EEG特征难以区分特发性和症状性病因,需要结合全面的临床资料作出诊断;⑤静止性脑结构病变不一定与中央颞区放电有直接关系。 相似文献
95.
96.
目的:报道常染色体显性遗传性枕叶癫痫一家系6例。方法:对先证者进行详尽的临床、脑电图(EEG)、录像脑电图(Video—EEG)、头MRA观察。结果:此家系祖孙三代6例,男性女性均有发病,患者大多为8~15岁起病,主要症状为发作性视幻觉、偏身麻木、头痛、呕吐。先证者EEG、Video—EEG、头颅MRA未见异常,家系中继发全面性强直阵挛发作患者EEG见枕颞区异常放电。结论:该家系患者的临床表现、EEG均符合枕叶癫痫诊断,并排除了颅内占位性及血管性病变。该家系符合常染色体显性遗传规律。 相似文献
97.
基于扩展Infomax ICA的ERP少次提取方法研究 总被引:1,自引:0,他引:1
事件相关电位(event related potential,ERP)提取是脑电研究的重点之一,目前临床上主要通过相干平均的方法来获取.由于脑电的非平稳性,使其需要大量重复刺激才能获得,对于受试者极不方便,也不利于ERP的实时检测.本文以反映大脑稀少认知事件的相关电位P300为例,采用扩展Infomax(extended informationmaximization)独立分量分析(independent component analysis,ICA)算法,先滤除眼动、工频干扰,再重构脑电数据,最后经少次叠加即可得到与通常需多次相干平均结果相近的比较满意的P300波形.说明ICA算法在ERP的峰值和潜伏期模式识别上具有较为明显的效果,具有潜在的临床工程应用价值. 相似文献
98.
Data are presented on the effects of generalized tonic-clonic seizures on the structure of the one-day sleep-waking cycle
in Krushinskii-Molodkina (KM) rats, which have a genetic predisposition to audiogenic convulsions. Spectral and correlation
analysis of EEG activity in the hippocampus, caudate nucleus, medial central nucleus of the thalamus, and in the somatosensory,
visual, and auditory regions of the cortex of these animals was carried out for time intervals before and after convulsions.
After seizures, rats showed a prolonged (up to 3.5 h) reduction in fast-wave sleep (FWS) with no subsequent compensatory increase
in this shase in the sleep-waking cycle, while a disturbance in slow-wave sleep (SWS) was minor and short-lived (not more
than 2 h). It is suggested that generalized paroxysmal attacks predominantly involve disorganization of the function of the
systems regulating FWS, while the synchronizing mechanisms of the brain, responsible for SWS, are affected to a lesser extent.
Laboratory of the Evolution of Sleep and Waking (Director G. A. Oganesyan), I. M. Sechenov Institute of Evolutionary Physiology
and Biochemistry, Russian Academy of Sciences, St. Petersburg. Translated from Fiziologicheskii Zhurnal imeni I. M. Sechenova,
Vol. 81, No. 10, pp. 1–8, October, 1995. 相似文献
99.
For some time, clinical reports have described impairment of affective and cognitive functions in iron deficient persons. Recent studies suggest that both brain biochemistry and cognitive performance capacity may be disrupted by inadequate intake of dietary iron, but the relationship of the possible neurophysiological effects to psychological ones is unclear. To examine the relationship of iron status to simultaneous measures of cortical activation and cognitive performance, 8 channels of electroencephalographic (EEG) data were recorded during a resting period and during the performance of several cognitive tasks in two groups of men. The EEG data were spectrally analyzed, and measures of total power and frequency of peak power in each of several bands of the power spectrum for each channel were used as predictors in multiple regression analyses with serum iron and serum ferritin as alternative criteria. Measures of power in the delta frequency in the resting period appeared relevant to iron status in both groups, perhaps indicating alertness or arousal level. Consistently in these regressions, the asymmetry of the EEG appeared relevant to iron and ferritin. These findings suggest that the combination of EEG and performance measures may help characterize the neuropsychological effects of trace element nutrition. 相似文献
100.
Although infants have been noted to have greater relative right or left frontal EEG as early as the neonatal period, other ways in which these newborns differ have not been reported. In this study, 48 newborns were divided on the basis of greater relative right versus greater relative left frontal EEG to determine whether these groups differed in other ways at the neonatal period including behavior, physiology, and biochemistry. We also were interested in whether these EEG patterns were related to any prenatal maternal variables including mood states (depression, anxiety, anger) and biochemistry as well as fetal activity. The greater relative right frontal EEG newborns had mothers with lower prenatal and postnatal serotonin and higher postnatal cortisol levels. The mothers of the greater relative right frontal EEG newborns also had greater relative right frontal EEG activation and lower vagal tone. The greater relative right frontal EEG newborns themselves had elevated cortisol levels, showed a greater number of state changes during sleep/wake behavior observations, and performed less optimally on the Brazelton Neonatal Behavior Assessment (T. B. Brazelton, 1973) including the habituation, motor, range of state, excitability, and depressive symptoms scales. These data suggest that greater relative right frontal EEG newborns may be at greater risk for developmental problems than those with greater relative left frontal EEG activation. In addition, a discriminant function analysis correctly classified 67% of the newborns' EEGs by prenatal maternal variables, suggesting that these might be used to target pregnant women for prenatal intervention. 相似文献