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1.
In order to investigate the characteristics of sensorimotor cortex during motor execution(ME), voluntary, stimulated and imaginary finger flexions were performed by ten volunteer subjects. Electroencephalogram(EEG) data were recorded according to the modified 10-20 International EEG System. The patterns were compared by the analysis of the motion-evoked EEG signals focusing on the contralateral(C3) and ipsilateral(C4) channels for hemispheric differences. The EEG energy distributions at alpha(8—13 Hz), beta(14—30 Hz) and gamma(30—50 Hz) bands were computed by wavelet transform(WT) and compared by the analysis of variance(ANOVA). The timefrequency(TF) analysis indicated that there existed a contralateral dominance of alpha post-movement event-related synchronization(ERS) pattern during the voluntary task, and that the energy of alpha band increased in the ipsilateral area during the stimulated(median nerve of wrist) task. Besides, the contralateral alpha and beta event-related desynchronization(ERD) patterns were observed in both stimulated and imaginary tasks. Another significant difference was found in the mean power values of gamma band(p0.01)between the imaginary and other tasks. The results show that significant hemispheric differences such as alpha and beta band EEG energy distributions and TF changing phenomena(ERS/ERD) were found between C3 and C4 areas during all of the three patterns. The largest energy distribution was always at the alpha band for each task. 相似文献
2.
XIAO Dan WAGN Ping 《江西蓝天学院学报》2008,(3)
对脑电信号进行特征提取和分类是脑机接口研究的核心问题,通过利用不同运动想象脑电信号能量熵的变化,从能量熵中提取特征,利用自定义基于统计理论分类方法进行分类,结果均达到90%以上。 相似文献
3.
以运动心理学的发展态势为主题,全面回顾了统计测量学、计算机科学、认知神经科学三大学科对运动心理学研究走向的影响,总结了现代科学对运动心理学发展的贡献,由此认为运动心理学的总体走向是主观客观化,即借助客观的现代科技手段揭示人们内在的主观心理特征。 相似文献
4.
"以声催力"的实验研究 总被引：1，自引：0，他引：1
吕新颖 《北京体育大学学报》2007,30(3):370-371
利用生物反馈训练仪和等速测力仪,对受试者进行"坐姿单手肩上直臂用力下压"和"坐姿肘部固定单手用力下压"两动作的吼声发力实验,试图证吼声发力能增强发力效果的真正原因.结果发现,脑电反馈信号的β波数据峰值和相对应峰力矩数据的密切相关;涉及到需要骤增胸腹内压的上肢运动动作,采用吼声发力都能提高发力的效果. 相似文献
5.
Xiao Zhang Dongrui Wu Lieyun Ding Hanbin Luo Chin-Teng Lin Tzyy-Ping Jung Ricardo Chavarriaga 《国家科学评论(英文版)》2021,8(4)
An electroencephalogram (EEG)-based brain–computer interface (BCI) speller allows a user to input text to a computer by thought. It is particularly useful to severely disabled individuals, e.g. amyotrophic lateral sclerosis patients, who have no other effective means of communication with another person or a computer. Most studies so far focused on making EEG-based BCI spellers faster and more reliable; however, few have considered their security. This study, for the first time, shows that P300 and steady-state visual evoked potential BCI spellers are very vulnerable, i.e. they can be severely attacked by adversarial perturbations, which are too tiny to be noticed when added to EEG signals, but can mislead the spellers to spell anything the attacker wants. The consequence could range from merely user frustration to severe misdiagnosis in clinical applications. We hope our research can attract more attention to the security of EEG-based BCI spellers, and more broadly, EEG-based BCIs, which has received little attention before. 相似文献
6.
Using time‐frequency analysis techniques to investigate the event‐related low‐frequency (delta: 0.5–4 Hz; theta: 4–8 Hz) activity of auditory event‐related potentials (ERPs) data of highly and average intelligent children, 18 intellectually gifted children, and 18 intellectually average children participated the present study. Present findings show that intellectually gifted children had significantly larger delta activity than their normal peers in mismatch negativity (MMN) component, while in P3a component, which originates from stimulus‐driven frontal attention mechanisms during task processing, intellectually gifted children had both significantly larger delta and theta activities than their normal peers. The present findings further supported that low‐frequency brain activity could be regarded as the basis of intelligence and cognitive functions, and spectral EEG time‐frequency analysis technique should be used to explore some new aspects of brain activity relating to intelligence. 相似文献
7.
目的:探究女子运动员力竭运动后脑电信号(EEG)与心率变异性(HRV)的变化,阐明其与运动性疲劳之间的关系。方法:随机选取19名女大学生运动员为实验对象,用布鲁斯(Bruce)运动方案进行力竭运动,检测其运动前后的EEG和HRV相关指标变化情况。结果:与运动前相比,疲劳后HRV时域指标SDNN、RMSSD、pNN50及频域指标LF和HF均非常显著性下降(P<0.01),但LF/HF比值却出现非常显著性上升(P<0.01);脑电信号方面,运动后疲劳状态下的α波和β波出现下降,δ波和θ波则出现上升趋势,且α波与运动前比在PZ区显著性下降(P<0.05),在FPZ区非常显著性下降(P<0.01),θ波与运动前比在FZ、FPZ区显著性上升(P<0.05),δ波在运动后有上升趋势但无显著差异。结论:力竭运动造成女子运动员心脏自主节律失衡,大脑皮层抑制,因此EEG与HRV变化可作为判别女子运动员力竭疲劳的有效指标。 相似文献
8.
人类运动想象会引起脑电信号的变化。基于脑电信号的时频域分析,结合C3、C4电极脑电信号间的相互关系,依据Fisher距离进行特征抽取,运用线性分类器进行分类。从运用到3名受试者的脑电数据中,分类效果因受试者而异,从65.0%到93.1%。 相似文献
9.
丛林 《上海体育学院学报》2006,30(4):63-65
采用实验法对拳击运动员表象竞赛时的脑电图进行监测,研究其在表象竞赛回合中的注意力与竞技水平的关系。结果表明:运动员注意力能力与参赛的重量级别无关,与竞技水平有关,不同竞技水平运动员之间呈显著性差异;注意力维持时间随运动员水平提高而延长;α波被抑制程度显示了运动员竞技水平的差异。结果反映了专项能力的特点。 相似文献
10.
阐述了近年来发展的高分辨脑电图所实现的技术途径，着重介绍了目前几种有代表性的从头皮电位测量值重建皮层电位分布的方法：解析求解 法、数值求解法（包括有限元法和边界元法）和表层成像技术等，系统地分析了这些方法的技术特点，讨论了它们的主要优势与不足。 相似文献