在脑机接口研究中,针对运动想象脑电信号的特征提取,采用了一种优化的基于小波包的ICA(独立成分分析)法,用于提取大脑在想象动作时产生事件相关去同步/同步(Event Related Desynchronization or Event Related Synchronization ERD/ERS...在脑机接口研究中,针对运动想象脑电信号的特征提取,采用了一种优化的基于小波包的ICA(独立成分分析)法,用于提取大脑在想象动作时产生事件相关去同步/同步(Event Related Desynchronization or Event Related Synchronization ERD/ERS)信号。利用小波包对脑电信号进行分解去除不同脑电信号之间的统计相关性,抽取包含ERD/ERS现象的特征频带,对每个特征频带分别进行ICA分解,获取与ERD/ERS现象相关的μ节律和β节律。最后引入ERD/ERS系数作为量化指标进行想象动作的识别。分类仿真结果表明,上述方法能够显著增强运动想象脑电信号的ERD/ERS特征信息,对比与独立使用某一种方法,两种方法结合更能有效的提取脑电信号特征波。展开更多
设计一套基于事件相关同步电位(Event related desynchron ization,ERD)和事件相关去同步电位(Event related synchronization,ERS)脑电信号反馈控制功能电刺激仪系统。当大脑想象残肢运动中,出现ERD/ERS脑电信号,经过特征提取和特征分...设计一套基于事件相关同步电位(Event related desynchron ization,ERD)和事件相关去同步电位(Event related synchronization,ERS)脑电信号反馈控制功能电刺激仪系统。当大脑想象残肢运动中,出现ERD/ERS脑电信号,经过特征提取和特征分类转换为控制命令去触发功能电刺激系统,实现对相应残肢的电刺激。实验结果成功实现了对残肢的电刺激。展开更多
The event-related desynchronization/synchronization(ERD/ERS) time courses of lower and upper alpha band rhythms during hand motor imagery are investigated respectively by Fourier Sectral Entropy (FSE) in this paper. B...The event-related desynchronization/synchronization(ERD/ERS) time courses of lower and upper alpha band rhythms during hand motor imagery are investigated respectively by Fourier Sectral Entropy (FSE) in this paper. By analyzing one group of BCI competition data, it was found that FSE within upper alpha band displays a pronounced increase and decrease over contralateral and ipsilateral brain areas respectively at the onset of hand motor imagery, which is corresponding to the antagonistic ERD/ERS patterns in previous studies. Different from the upper alpha activity pattern, FSE within lower alpha band displays a consistent increase over both two hemispheres hand representative areas. The preliminary results show that FSE could disclose the different behaviors of the upper and lower alpha band rhythms so that a new idea with the complexity measure is provided to characterize functional dissociation of lower and upper frequency alpha rhythms in relation to hand motor imagery.展开更多
文摘在脑机接口研究中,针对运动想象脑电信号的特征提取,采用了一种优化的基于小波包的ICA(独立成分分析)法,用于提取大脑在想象动作时产生事件相关去同步/同步(Event Related Desynchronization or Event Related Synchronization ERD/ERS)信号。利用小波包对脑电信号进行分解去除不同脑电信号之间的统计相关性,抽取包含ERD/ERS现象的特征频带,对每个特征频带分别进行ICA分解,获取与ERD/ERS现象相关的μ节律和β节律。最后引入ERD/ERS系数作为量化指标进行想象动作的识别。分类仿真结果表明,上述方法能够显著增强运动想象脑电信号的ERD/ERS特征信息,对比与独立使用某一种方法,两种方法结合更能有效的提取脑电信号特征波。
文摘设计一套基于事件相关同步电位(Event related desynchron ization,ERD)和事件相关去同步电位(Event related synchronization,ERS)脑电信号反馈控制功能电刺激仪系统。当大脑想象残肢运动中,出现ERD/ERS脑电信号,经过特征提取和特征分类转换为控制命令去触发功能电刺激系统,实现对相应残肢的电刺激。实验结果成功实现了对残肢的电刺激。
基金National Natural Science Foundation of China (No.30370395and30670534)Chinese Post-doctoral Science Foundation (No.20070410380)
文摘The event-related desynchronization/synchronization(ERD/ERS) time courses of lower and upper alpha band rhythms during hand motor imagery are investigated respectively by Fourier Sectral Entropy (FSE) in this paper. By analyzing one group of BCI competition data, it was found that FSE within upper alpha band displays a pronounced increase and decrease over contralateral and ipsilateral brain areas respectively at the onset of hand motor imagery, which is corresponding to the antagonistic ERD/ERS patterns in previous studies. Different from the upper alpha activity pattern, FSE within lower alpha band displays a consistent increase over both two hemispheres hand representative areas. The preliminary results show that FSE could disclose the different behaviors of the upper and lower alpha band rhythms so that a new idea with the complexity measure is provided to characterize functional dissociation of lower and upper frequency alpha rhythms in relation to hand motor imagery.
