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1.
Poddubnaya  E. P. 《Neurophysiology》2004,36(2):138-147
Computer periodometric analysis of EEG recorded from 169 healthy schoolchildren allowed us to calculate the quantitative indices characterizing the direction and intensity of dynamic changes in cerebral electrical activity induced by a hyperventilation test. Three main types of EEG reactions to hyperventilation observed in children of different age groups have been classified. The dependence of the frequency of types of EEG reactions of healthy children to the hyperventilation test on the age of the tested subjects and EEG type in the resting state was demonstrated.  相似文献   

2.
Inphase interactions among EEG signals recorded using eight electrodes were investigated. The inphase interaction parameters are presented in two ways: (1) matrix form in which the number of inphase interactions are tabulated; and (2) histogram in which the number of inphase interactions are plotted pair-wise between two sites as a function of phase delays in milliseconds. The highest number of interactions occurs between 0 and 8 ms in normal brains. The values of interaction parameters are enhanced by various activities. For example, inphase interaction parameters increase in the motor area in the right hemisphere if the EEG is recorded during repeated left fist clenching. Inphase interactions are drastically altered by the presence of a tumor. We studied the inphase interactions of the EEG of a patient having an occipital tumor. The interaction parameters are greatly diminished in this area, indicating a severe impairment of neuronal communications between both hemispheres in the occipital region. The confidence limits of the changes in inphase interaction parameters during fist clenching are tested statistically using the Student's t test. The test shows that the interaction parameters increase, in general, with 1–5% confidence limits in respective cortex areas as a result of fist clenching.  相似文献   

3.
目的:对徐州学龄期儿童的肥胖现状进行调查,分析其肥胖原因,以期找到有效的预防方法。方法:随机选取2014年1月-2016年1月徐州市学龄期儿童1021例,采用自理调查量表收集儿童及其父母的基本情况,统计儿童肥胖发生率,采用Logistic多因素回归分析儿童肥胖的影响因素。结果:男童肥胖率为11.15%(58/520),女童肥胖率为5.79%(29/501),男童肥胖率明显高于女童(P0.05);Logistic多因素回归分析显示,儿童肥胖危险因素有家族肥胖史(OR=3.647)、食欲(OR=2.065)、垃圾食品(OR=3.032)、甜食(OR=2.937),保护因素为周末运动时间(OR=-0.865)、体育特长(OR=-0.641)。结论:徐州学龄期儿童肥胖情况较为严重,应当控制肥胖儿童卡路里的摄入,积极进行体育锻炼,从各方面进行防治。  相似文献   

4.
Electroencephalographic examination of 7-to 9-year-old children with sensorineural deafness of degrees II and III included EEG recording in the resting state, in the course of reaction of activation (at opening of the eyes), under conditions of rhythmic photostimulation with frequencies of 4, 6, 9, and 12 sec−1 and under those of the hyperventilation test. The results allow us to conclude that systems responsible for generation of EEG in hard-of-hearing children demonstrate some functionally immaturity. The following facts confirm the above conclusion. As compared with the norm, greater normalized spectral powers (SPs) of the delta and theta rhythms, a higher intensity of electrogenesis (integral power of oscillations) within all frequency ranges, and a smaller mean frequency of the dominant rhythm were typical of hard-of-hearing children. In these children, the reaction of activation in the majority of cases looked like incomplete suppression of the alpha rhythm. Upon rhythmic photostimulation, hard-of-hearing boys and girls demonstrated following of the rhythm at frequencies of 4 and 6 sec−1 while children with normal hearing demonstrated that at 9 and 12 sec−1 frequencies. The characteristics of EEG reactions under the conditions of the hyperventilation test reflected the immaturity of the fronto-thalamic controlling system, as well as certain dysfunction of lower brainstem regions in children with disorders of hearing. Neirofiziologiya/Neurophysiology, Vol. 40, No. 2, pp. 137–146, March–April, 2008.  相似文献   

5.
The objective of this work was to explore Neurofeedback (NFB) effects on EEG current sources in Learning Disabled (LD) children, and to corroborate its beneficial consequences on behavioral and cognitive performance. NFB was given in twenty 30-min sessions to 11 LD children to reduce their abnormally high theta/alpha ratios (Experimental Group). Another five LD children with the same characteristics received a placebo treatment (Control Group). In the Control Group no changes in behavior or EEG current source were observed. In the Experimental Group, immediately after treatment children showed behavioral and cognitive improvements, but current source analysis showed few modifications; however, 2 months after treatment many changes occurred: a decrease in current of frequencies within the theta band, mainly in left frontal and cingulate regions, and enhancement in current of frequencies within the alpha band, principally in the right temporal lobe and right frontal regions, and of frequencies within the beta band, mainly in left temporal, right frontal and cingulate cortex regions. In conclusion, NFB is a possibly efficacious treatment for LD children with an abnormally high theta/alpha ratio in any lead. The changes observed in EEG current sources may reflect the neurophysiological bases of the improvement that children experienced in their behavioral and cognitive activities.  相似文献   

6.
EEG is traditionally described as a neuroimaging technique with high temporal and low spatial resolution. Recent advances in biophysical modelling and signal processing make it possible to exploit information from other imaging modalities like structural MRI that provide high spatial resolution to overcome this constraint1. This is especially useful for investigations that require high resolution in the temporal as well as spatial domain. In addition, due to the easy application and low cost of EEG recordings, EEG is often the method of choice when working with populations, such as young children, that do not tolerate functional MRI scans well. However, in order to investigate which neural substrates are involved, anatomical information from structural MRI is still needed. Most EEG analysis packages work with standard head models that are based on adult anatomy. The accuracy of these models when used for children is limited2, because the composition and spatial configuration of head tissues changes dramatically over development3. In the present paper, we provide an overview of our recent work in utilizing head models based on individual structural MRI scans or age specific head models to reconstruct the cortical generators of high density EEG. This article describes how EEG recordings are acquired, processed, and analyzed with pediatric populations at the London Baby Lab, including laboratory setup, task design, EEG preprocessing, MRI processing, and EEG channel level and source analysis.   相似文献   

7.
In 76 healthy persons (right-handed men and women), we recorded background EEG and event-related potentials from the C3 and C4 sites; tests were performed within the framework of an experimental situation requiring internal measuring-off of the time intervals. To limit the interval, the tested person had to push a button; he/she did not know the precise value of the interval, which was preset by the experimenter, and was informed only of the lower and upper limits of this interval, 17 to 23 sec. The person obtained information about the coincidence/noncoincidence of the measured-off and preset intervals via visual feedback; the respective signal was presented 2 sec after measuring-off had been completed. In the case where the intervals coincided with each other, the person should confirm this by pushing the button next time (confirming push). We characterized the parameters of the measured-off time interval by the following indices: (i) measuring-off efficacy (accuracy of fitting the preset interval), (ii) estimation tendency (measured-off interval/preset standard interval ratio), and (iii) coefficient of variation (CV) of the measured-off interval. Features of the subject's personality were estimated using Eysenck's (PEN) and Cattell's (16PF) questionnaires. We found correlations of the powers of the background EEG rhythms (beta1, beta2, and alpha/theta ratio) and characteristics of the measured-off time interval. In addition, we observed significant positive correlations between the estimation tendency and extraversion index and between CV of the interval and urge toward domination and protension indices. Negative correlations were observed between the measuring-off efficacy and protension (suspiciousness), between the estimation tendency and anxiety, and between the CV of the interval and age of the subjects. We support the conclusion that correlations between the patterns of EEG potentials, peculiarities of measuring-off of the time interval, and psychological features of the personality are to a noticeable extent mediated by the individual specificity of the neurodynamics.  相似文献   

8.
The dynamic behavior of scalp potentials (EEG) is apparently due to some combination of global and local processes with important top-down and bottom-up interactions across spatial scales. In treating global mechanisms, we stress the importance of myelinated axon propagation delays and periodic boundary conditions in the cortical-white matter system, which is topologically close to a spherical shell. By contrast, the proposed local mechanisms are multiscale interactions between cortical columns via short-ranged non-myelinated fibers. A mechanical model consisting of a stretched string with attached nonlinear springs demonstrates the general idea. The string produces standing waves analogous to large-scale coherent EEG observed in some brain states. The attached springs are analogous to the smaller (mesoscopic) scale columnar dynamics. Generally, we expect string displacement and EEG at all scales to result from both global and local phenomena. A statistical mechanics of neocortical interactions (SMNI) calculates oscillatory behavior consistent with typical EEG, within columns, between neighboring columns via short-ranged non-myelinated fibers, across cortical regions via myelinated fibers, and also derives a string equation consistent with the global EEG model.  相似文献   

9.
Electroencephalogram (EEG) is often used in the confirmatory test for brain death diagnosis in clinical practice. Because EEG recording and monitoring is relatively safe for the patients in deep coma, it is believed to be valuable for either reducing the risk of brain death diagnosis (while comparing other tests such as the apnea) or preventing mistaken diagnosis. The objective of this paper is to study several statistical methods for quantitative EEG analysis in order to help bedside or ambulatory monitoring or diagnosis. We apply signal processing and quantitative statistical analysis for the EEG recordings of 32 adult patients. For EEG signal processing, independent component analysis (ICA) was applied to separate the independent source components, followed by Fourier and time-frequency analysis. For quantitative EEG analysis, we apply several statistical complexity measures to the EEG signals and evaluate the differences between two groups of patients: the subjects in deep coma, and the subjects who were categorized as brain death. We report statistically significant differences of quantitative statistics with real-life EEG recordings in such a clinical study, and we also present interpretation and discussions on the preliminary experimental results.
Zhe ChenEmail:
  相似文献   

10.
Different types of phase coupling between and within EEG signals are theoretically explained and coupling-related analysis strategies are reported. Effects of synchronization have been distinguished from effects signal transfer (propagation), where both are designated by a phase coupling. Six examples of phase coupling analysis are presented. The EEG data are derived from our previous investigations and analysis results are complemented by modelling and simulation studies.  相似文献   

11.
Electroencephalogram (EEG) is generally used in brain–computer interface (BCI), including motor imagery, mental task, steady-state evoked potentials (SSEPs) and P300. In order to complement existing motor-based control paradigms, this paper proposed a novel imagery mode: speech imagery. Chinese characters are monosyllabic and one Chinese character can express one meaning. Thus, eight Chinese subjects were required to read two Chinese characters in mind in this experiment. There were different shapes, pronunciations and meanings between two Chinese characters. Feature vectors of EEG signals were extracted by common spatial patterns (CSP), and then these vectors were classified by support vector machine (SVM). The accuracy between two characters was not superior. However, it was still effective to distinguish whether subjects were reading one character in mind, and the accuracies were between 73.65% and 95.76%. The results were better than vowel speech imagery, and they were suitable for asynchronous BCI. BCI systems will be also extended from motor imagery to combine motor imagery and speech imagery in the future.  相似文献   

12.
目的:探讨托吡酯联合左乙拉西坦对难治性癫痫患儿脑电活动、免疫球蛋白和生活质量的影响。方法:选取2014年5月~2019年5月期间我院收治的80例难治性癫痫患儿,按照随机数字表法将患儿分为研究组(n=40)、对照组(n=40),均予原抗癫痫药物治疗方案,并积极预防并发症,在此基础上,对照组患儿给予托吡酯治疗,研究组在对照组的基础上联合左乙拉西坦治疗,比较两组患儿疗效、脑电活动、免疫球蛋白水平、不良反应、生活质量。结果:研究组治疗3个月后的临床总有效率为90.00%(36/40),高于对照组的70.00%(28/40)(P0.05)。两组患儿治疗3个月后癫痫样放电量、α波、β波、θ波、δ波数量均下降,且研究组低于对照组(P0.05)。两组患儿治疗3个月后免疫球蛋白A(Ig A)、免疫球蛋白G(Ig G)水平均升高,且研究组高于对照组(P0.05);两组患儿治疗3个月后免疫球蛋白M(Ig M)水平未见显著变化,且组间比较无差异(P0.05)。两组患儿治疗3个月后发作担忧、社会功能、情绪、精力等评分均升高,且研究组高于对照组(P0.05)。两组不良反应发生率对比未见统计学差异(P0.05)。结论:难治性癫痫患儿经托吡酯联合左乙拉西坦治疗后,患儿脑电活动得到有效控制,患儿免疫功能及生活质量均得到有效改善,用药安全性较好,具有一定的临床应用价值。  相似文献   

13.
In this paper, we introduce a Levins-type metapopulation model with empty and occupied patches, and dispersing population. We structure the proportion of occupied patches according to the patch-occupancy age. We observe that patch-occupancy age may destabilize the metapopulation, leading to persistent oscillations. We also allow for the dispersal rate to vary with the proportion of empty patches in a monotone or unimodal way. The unimodal dependence leads to multiple non-trivial equilibria and bistability when the reproduction number of the metapopulation < 1 but greater than a lower critical value *. We show that the metapopulation will persist independently of its initial status if > 1.  相似文献   

14.
目的:探究卡马西平与丙戊酸钠对儿童癫痫部分发作患儿发作脑电图影响,并实施组间对照研究。方法:选择2017年1月至2020年1月于我院接受治疗的81例癫痫部分性发作患儿为研究对象,按照其接受治疗的差异将其分为卡马西平组(40例)和丙戊酸钠组(41例),对比两组患儿接受药物治疗后脑电图以及脑电地形图变化情况。结果:(1)卡马西平组患儿接受治疗后脑电图检测显示间歇期痫样活动减少≥50%者占比高达67.50%(27/40),而丙戊酸钠组占比仅为43.90%(18/41),两组比较差异明显(P<0.05);(2)脑电背景活动变化比较显示,治疗后卡马西平组患儿α波无影响者占比65.00%,明显高于丙戊酸钠组36.59%,同时丙戊酸钠组患儿δ波数(20 s内)药物治疗后变化较卡马西平组更为明显;(3)脑电功率比较显示,卡马西平组患儿治疗后仅θ频段相对功率出现明显变化(P<0.05),但丙戊酸钠组患儿α频段相对功率、θ频段相对功率和θ频段绝对功率均出现明显变化(P<0.05)。结论:丙戊酸钠应用于儿童癫痫部分性发作时患儿脑电背景活动会明显变慢,甚至有出现间歇期痫样放电的风险,而卡马西平相对更为稳定,对患儿脑电图的影响更小,安全性更高。  相似文献   

15.
目的:探讨脑电图睡眠纺锤波在植物状态病人预后判别中的价值。方法:在长程脑电监测下观察植物状态病人的睡眠纺锤波,与其意识恢复进行相关性分析,并预测患者意识恢复的敏感性、特异性及准确性。结果:28例患者中,12例有纺锤波,其中9例意识恢复;16例无纺锤波患者中,14例未恢复意识。纺锤波的有无与患者意识恢复有相关性,P值<0.01。脑电图睡眠纺锤波对植物状态患者意识恢复判断的敏感性(83.25%)、特异性(81.82%)、准确性(82.14%)。结论:脑电图睡眠纺锤波可较准确预测植物状态患者的意识恢复能力,可作为临床评估植物状态患者意识恢复能力的辅助方法。  相似文献   

16.
Drawing on two assumptions: that menopause is an instrument for the efficient regulation of the duration of a biologically expensive state, and that people have children in order to obtain support from them in old age, we set out a new idea that seeks to explain both the occurrence of menopause and its timing. On the basis of the notion that the purpose of having children is to obtain support in old age, we perceive menopause as an upper limit to the fertile state, when a continued ability to give birth to children would not generate the desired support. The conjecture yields specific testable predictions, and can be assessed against the “reproductive conflict” hypothesis. Being supported by one’s offspring is a distinctive feature of humans; in this context, we cannot rely on animal studies in evolutionary biology and related fields to help us to ascertain something that is specific to humans.  相似文献   

17.
Blood was obtained from 564 11-yr-old children who had participated since birth in a multidisciplinary health and development study. Serum zinc concentration did not differ between the boys and the girls (mean±SD: 91=17 μg/100 mL,n=453). Five-6% of serum zinc values were low; although there was a weak correlation with height, none of the boys with low values were below the 10th percentile for height for this group. Serum copper concentration (112±24 μg/100 mL,n=454) was unrelated to sex, height, weight, body mass index, socioeconomic status (SES), or iron status. Blood selenium concentration (49±10 ng/mL,n=564) was lower than previously reported for Dunedin children; it was higher in children in the lower SES categories. The data represent normal values for healthy, 11-yr-old NZ children.  相似文献   

18.
目的:分析中老年阴道炎患者阴道毛滴虫感染情况,为中老年阴道炎的防治提供依据。方法:对2016年9月~2019年9月来我院就诊的中老年阴道炎患者的阴道分泌物进行阴道毛滴虫检查,同时通过问卷调查方法收集患者的病历资料,回收有效问卷200份,分析不同年龄、季节、职业、生活习惯、性生活情况患者的阴道毛滴虫感染状况。结果:中老年阴道炎患者阴道毛滴虫感染率为10.50%,其中45~50岁年龄段阴道炎患者阴道毛滴虫感染率最高,占19.15%,71~80岁年龄段阴道炎患者阴道毛滴虫感染率最低,占2.78%,不同年龄段阴道炎患者阴道毛滴虫感染率比较有统计学差异(P0.05)。春季、夏季阴道毛滴虫感染率显著高于秋季、冬季(P0.05)。牧民、农民阴道炎患者阴道毛滴虫感染率显著高于工人和公职人员的感染率(P0.05),牧民、农民阴道炎患者阴道毛滴虫感染率无明显差异(P0.05)。经常性清洁外阴的阴道炎患者阴道毛滴虫感染率显著低于非经常性清洁外阴的患者(P0.05)。有性生活阴道炎患者阴道毛滴虫感染率显著高于无性生活患者(P0.05),有性生活应用避孕套的阴道炎患者阴道毛滴虫感染率显著低于不应用避孕套患者(P0.05)。结论:中老年阴道炎患者阴道毛滴虫感染率较高,春季、夏季是阴道毛滴虫感染的高峰期,中年患者感染率高于老年患者,农民、牧民、服务人员和非经常性清洁外阴的患者阴道毛滴虫感染率较高,且有性生活没有应用避孕套者感染率更高,应做好以上高危人群的防治工作,以降低阴道毛滴虫的感染率。  相似文献   

19.
20.
Research on personality and circadian typology indicates evening-type women are more impulsive and novelty seeking, neither types are more anxious, and morning types tend to be more active, conscientious, and persistent. The purpose of this study is to examine the differences between circadian typologies in the light of the Zuckerman's Alternative Five-Factor Model (AFFM) of personality, which has a strong biological basis, in an adult sample of 412 women 18 to 55 yrs of age. The authors found morning-type women had significant higher scores than evening-type and neither-type women on Activity, and its subscales General Activity and Work Activity. In contrast, evening-type women scored significantly higher than morning-type women on Aggression-Hostility, Impulsive Sensation Seeking, and its subscale Sensation Seeking. In all groups, results were independent of age. These findings are in accordance with those previously obtained in female student samples and add new data on the AFFM. The need of using personality models that are biologically based in the study of circadian rhythms is discussed. (Author correspondence: )  相似文献   

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