生命科学中的物理问题讲座第八讲人脑电图的复杂性

利用非线性动力学复杂性的测度研究了人脑电图在不同的功能状态下的信息传递，并定义了不同层次的复杂性的测度，认为这种方法可作为研究人脑高级功能的一种方法。     

脑电信号的标度分析及其在睡眠状态区分中的应用

脑电信号具有长程幂律相关性及多重分形的标度特性,并随生理病理状态改变.本文首次针对睡眠脑电信号应用单重分形去趋势波动分析(detrended fluctuation analysis,简记为DFA)方法与多重分形奇异谱对睡眠脑电信号的标度特征进行系统的对比研究.发现DFA标度指数α对于不同导联和样本组间的差异较为敏感,随睡眠状态的变化不规律;而多重分形奇异强度区间Δα随睡眠状态的变化更为规律,睡眠Ⅰ期至Ⅳ期不断增大,并且导联间差异和样本组间差异均较小.多重分形Δα参数更适合作为判定睡眠状态的定量参数.     

儿童额叶癫痫临床和长程视频脑电图特征

目的通过对46例儿童额叶癫痫患儿的临床表现、长程视频脑电图（VEEG）特点进行分析,提高对儿童额叶癫痫的认识。方法收集2008年12月至2014年8月儿科门诊及住院确诊的46例儿童额叶癫痫病例的资料,回顾性分析其临床表现、VEEG及神经影像学等特征。结果本组患儿发病年龄最小11个月,最大15岁。46例患儿共监测到临床发作258次,明确临床发作34例,14.7%仅于清醒期发作,61.8%仅在睡眠期发作,23.5%在清醒、睡眠中均有发作;临床发作形式包括额叶失神、局部阵挛发作、偏转性强直、姿势性强直、过度运动性自动症、口咽自动症、发声、发笑发作、临床下放电和自主神经性发作等。73.9%患儿记录到发作间期额叶为主的癫痫样放电,63.0%患儿记录到发作期额叶为主的癫痫样放电。结论儿童额叶癫痫临床发作频繁、短暂,以睡眠期发作为主,临床表现复杂多样,易漏诊;长程VEEG可监测到儿童额叶癫痫发作期临床及异常脑电图表现,可提供明确诊断率。     

脑电信号的多尺度排列熵分析

本文利用多尺度排列熵对正常脑电信号和癫痫脑电信号进行了详细的分析和比较,研究了脑电图信号多尺度排列熵值和年龄的关系以及尺度因子对多尺度排列熵值的影响.通过对处于各个年龄段的22组正常人和22组患有癫痫人群的脑电图进行多尺度排列熵分析,发现在相同年龄段的人群中,正常脑电信号的多尺度排列熵值要高于癫痫脑电信号,熵值平均高出约0.19,约7.9%.另外,在尺度因子小于15的情况下,对于在30到35的年龄段正常人群,其多尺度排列熵值最大,随着年龄段的增大或降低熵值都一定程度的降低.结果证明,多尺度排列熵可以成功区分正常脑电信号和癫痫脑电信号,并且熵值可以正确地反映人体大脑发育的一般过程.     

脑电图监测对额叶癫痫发作性患者的早期诊断及术中辅助定位价值研究

癫痫的早期诊断对预后恢复具有重要意义,因此本文对脑电图在癫痫患者术前诊断和辅助手术治疗方面的应用价值进行了综合性探究.选择经临床确诊为额叶癫痫的60例患者作为研究对象进行回顾性研究,术前、术后分别通过头颅核磁共振和脑电图对患者进行检查,比较两种检测方法的灵敏度、特异度和准确率.经研究发现,脑电图与MRI检查相比,其诊断...     

Phase Locking Phenomena and Electroencephalogram-Like Activities in Dynamic Neuronal Systems

We study signal detection and transduction of dynamic neuronal systems under the influence of external noise,white and coloured. Based on simulations, we show explicitly phase locking phenomena between the output and the input of a single neuron and Electroencephalogram-like activities on neural networks with small-world connectivity. The numerical results prove that the dynamic neuronal system can be adjusted to an optimal sensitive state for signal processing in the presence of additive noise.     

The modulation of brain functional connectivity with manual acupuncture in healthy subjects:An electroencephalograph case study

Manual acupuncture is widely used for pain relief and stress control.Previous studies on acupuncture have shown its modulatory effects on the functional connectivity associated with one or a few preselected brain regions.To investigate how manual acupuncture modulates the organization of functional networks at a whole-brain level,we acupuncture at ST36 of a right leg to obtain electroencephalograph(EEG) signals.By coherence estimation,we determine the synchronizations between all pairwise combinations of EEG channels in three acupuncture states.The resulting synchronization matrices are converted into functional networks by applying a threshold,and the clustering coefficients and path lengths are computed as a function of threshold.The results show that acupuncture can increase functional connections and synchronizations between different brain areas.For a wide range of thresholds,the clustering coefficient during acupuncture and postacupuncture period is higher than that during the pre-acupuncture control period,whereas the characteristic path length is shorter.We provide further support for the presence of "small-world" network characteristics in functional networks by using acupuncture.These preliminary results highlight the beneficial modulations of functional connectivity by manual acupuncture,which could contribute to the understanding of the effects of acupuncture on the entire brain,as well as the neurophysiological mechanisms underlying acupuncture.Moreover,the proposed method may be a useful approach to the further investigation of the complexity of patterns of interrelations between EEG channels.     

健康教育表格在长程视频脑电图患儿健康教育中的应用

目的探讨健康教育表格在长程视频脑电图患儿检测中的应用。方法将医院儿科2013年1月—6月200例视频脑电图监测患儿分为观察组与对照组,实施健康教育表格前100例的患者分为对照组;实施健康教育表格后的100例患者为观察组。比较两组患儿脑电图检测完成率、成功率。结果观察组患者脑电图检测成功率明显高于对照组,差异有显著意义(P0.05)。结论及时有效的健康教育处方有利于提高患儿视频脑电图检查的完成率和成功率,对明确疾病诊断有重要意义。     

The Relationship Between Relative Hydration Free Energies of 99mTcON2S2 Complexes and Their Brain Uptakes

A thermodynamic integration dual-transform method was firstly applied to calculating the relative hydration free energies of ^99mTcON2S2 complexes. The relationship between the brain uptakes(B, U. ) of ^99mTcON2S2 complexes with different substituted functional groups and their relative hydration free energies was investigated. The simulation results show that the experiment brain uptake(B. U. ) data are strongly influenced by the relative hydration free energies of ^99mTcON2S2 complexes, thus the simulations can provide the useful information for the medicine design of ^99mTc brain imaging agents.