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1.
为探究脑电空间关联信息与不同情感状态之间对应关系,基于SEED(SJTU Emotion EEG Dataset)情感脑电数据集,计算实验采集的不同导联脑电的皮尔逊相关系数,通过小波变换获取脑电导联之间的小波相干系数,利用Hilbert变换提取各个导联脑电的瞬时相位,计算脑电相位同步指数。然后分别将皮尔逊相关系数、小波相干系数、相位同步指数作为特征,采用支持向量机分类器实现正性、负性、中性三种情感状态的有效分类。仿真结果表明,脑电的空间关联特征用于情感识别是有效的,可以达到91.5%的情感识别精度;利用脑电微分熵的皮尔逊相关系数获得了93.7%的平均分类准确率;并且脑电γ节律相比α、β节律更有利于情感识别。该研究可以应用于情感脑机接口系统。  相似文献   

2.
已有研究发现人静息态时大脑皮层活动处于近临界状态,且具有优化的信息传输效率.然而大脑在感觉刺激状态下脑电临界动力学特征少有研究.此外,轻音乐被报道对于抑郁症、精神分裂症及术后损伤均具有较好的辅助治疗作用.本文应用临界动力学理论,研究了轻音乐刺激状态时大脑皮层脑电临界动力学特性.我们记录了26名被试在闭眼、睁眼及闭眼听音乐状态的脑电信号,对3种状态进行了频率特性和临界动力学特征分析.结果显示人在睁眼状态,全脑脑电信号活动率显著高于闭眼和听音乐状态.相对于闭眼的临界状态,音乐状态和睁眼状态分别趋向于次临界和超临界的状态,即趋向于系统的低耗能态和高耗能态.说明轻优美的音乐可以帮助大脑进入更好的休息状态,没有大尺度的活动发生,这为音乐治疗提供了有价值的实验依据.  相似文献   

3.
本文报告急性一氧化碳中毒致迟发性脑病4例。其病理改变为缺氧后所致皮层或基底节局灶脑软化及皮层下白质广泛的脱髓鞘改变。病史、“假愈期”、神经精神症状及锥体外系症状是诊断本病的要点。高压氧是治疗和预防本病的关键。  相似文献   

4.
西红花甙对缺血性脑梗塞的药效研究   总被引:3,自引:0,他引:3  
西红花甙经十二指肠给药,对电凝阻断大脑脑中动脉造成的局灶性脑缺血有明显保护作用,能明显缩小脑梗塞灶,使梗塞后动物的活动行为障碍减轻,同时脑指数、MDA含量明显降低。  相似文献   

5.
运用时窗复杂度序列来分析睡眠脑电,减少了非平稳性及状态空间的不均匀性造成的脑状态信息的丢失,在一定程度上克服了复杂度的自身的局限,有助于不同睡眠期状态特征的提取.另外本文采用ICA、小波变换等方法对脑电进行预处理,实验表明它们能有效地去除脑电中的一些生理干扰,有利于提高复杂度算法在睡眠分期应用中的精确度.  相似文献   

6.
通过计算多导脑电的互信息传输时间序列的复杂度,研究了心算任务和安静状态下不同认知水平的对象脑电特异表现.结果表明,不同的实验状态、不同认知能力的被试者以及大脑的不同部位均可对互信息复杂度产生显著影响.抑郁症在心算任务下的互信息传输复杂度显著低于(P<0.001)安静闭目状态下的复杂度,而正常对照组虽然在心算任务下的脑电互信息传输复杂度也较安静闭目状态时有所下降,但不具有统计意义.据此推测,完成认知作业时的脑电互信息复杂度在一定程度上反映了认知水平的不同.  相似文献   

7.
脑对双耳听觉信息整合的神经机制   总被引:1,自引:0,他引:1  
综述近60 a来有关脑对双耳听觉信息整合的神经机制的研究进展.首先介绍了脑处理双耳信息的神经解剖学基础,双耳神经元的分类及其生理特性,以及双耳神经元在听觉系统的拓扑学分布研究;然后对脑处理双耳听觉信息研究的热点领域进行了重点探讨,综述了上橄榄复合体、下丘和听皮层双耳神经元对双耳时间差和双耳强度差的编码方式,以及脑通过对这些参数的编码来分析声源方位的神经生理学研究进展;最后对该领域未来研究方向作展望.  相似文献   

8.
大脑皮层抑制状态时条件反射的形成   总被引:1,自引:1,他引:0  
在动物大脑皮层抑制的确定时相中,借条件反射建立的特点,可以制断皮层活动的机能特性。前曾报告,在药物诱导睡眠过程中的麻醉时相状态下,大脑皮层细胞工作能力水平降低。这时建立的条件反射较清醒时需要更多次结合才能出现,条件反射的潜伏期较长,反射量较小,且不能彻底巩固,而迅速消失。当抑制进一步加深时,或在个别分析器皮层代表区引起深度抑制时,建成条件反射需要什么条件?具有那些特性?这是值得深入研究的问题,本文将报导狗在抑制时相中形成运动防御条件反射的条件,以及这种条件反射的特性。  相似文献   

9.
本文对194例正常人右胸、上腹导联进行体表心电图检测.从其QRS波型分布结果及筛选出的V_4R、MR、和ME三个导联出现QS波的特导性,结合有关文献报道提出除V_4R外,MR和ME亦应列为诊断右室梗塞的有价值的检查导联.对急性下壁心肌梗塞患者,在常规12个导联以外,加V_4R、MR和ME三个导联协同检测,可以提高RVMI的检测率和早期诊断的可靠性.  相似文献   

10.
脑电中不同类型的基本节律在不同生理条件下特征不同,有效提取这些特征对于实现脑电定量分析具有重要作用。简要分析了谐波小波独特的优势,研究了基于离散谐波小波包方法精确提取脑电基本节律的问题,得到了两种反映节律特征的量化参数:单个导联上各节律在某时刻的频带能量比例(FBER-S)和某一导联脑电信号在某一频段内的能量占所有导联在该频段内能量的百分比(FBER-A)。对临床病例数据分析表明,这两种特征参数呈现的特点与确诊病例的病症特点吻合得很好,说明它们能够作为临床诊断和长时程脑电监护的有效辅助诊断依据。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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