摘要
基于脑电图(Electroencephalography,EEG)信号的运动想象(Motor Imagery,MI)意图识别是脑机接口(BrainComputer Interface,BCI)研究中的重要问题.然而,EEG信号存在严重的个体性差异,不同被试之间的EEG信号特征空间分布差异很大,不同被试之间的分类模型不能通用.针对这一问题,提出一种基于欧式空间的加权逻辑回归迁移学习方法,算法首先将不同被试的EEG数据进行欧几里得空间对齐,使各信号更加相似,减少差异性,然后计算特定被试共空间模式(Common Spatial Pattern,CSP)获得不同的特征值,并计算这些特征值的KL(Kullback-Leibler)散度,进而利用KL散度调整迁移学习的加权逻辑回归算法,得到分类模型.实验结果表明:对于BCI竞赛IV中的数据集2a,提出的方法可以极大地提升BCI的学习性能,算法分类准确率比基线算法(线性判别分析)高出15%.在数据样本增多的情况下,被试的分类准确性也得到了明显的提升,和同类算法相比,分类准确率提升4%,说明提出的算法能进一步提高BCI的学习性能,改善分类模型的通用性问题.
Motor imagery(MI)intention recognition based on electroencephalography(EEG)signals is an important issue in brain-computer interface(BCI)research.However,EEG signals have serious individual differences,while the spatial distribution of EEG signal characteristics between different subjects is very different,and the classification model between different subjects cannot be universal.To solve this problem,this paper proposes a weighted logistic regression transfer learning method based on Euclidean space.The algorithm first aligns the EEG data of different subjects in Euclidean space to make the signals more similar and reduce the difference,and calculate the different feature values obtained by the common spatial pattern(CSP)of a specific subject.Then,it calculates the KL(Kullback-Leibler)divergence of these eigenvalues,using the KL divergence to adjust the weighted logistic regression algorithm of transfer learning to obtain the classification model.The experimental results show that,for the data set 2a in the BCI competition IV,the proposed method greatly improves the learning performance of BCI,and the classification accuracy is 15%higher than that of the baseline algorithm(Linear Discriminant Analysis).In case of an increase in data samples,the classification accuracy of the subjects has been significantly improved.Compared with similar algorithms,the classification accuracy of the proposed algorithm increases by 4%,indicating that the algorithm in this paper furtherly improves the BCI learning performance and the generality of the classification model.
作者
陈黎
龚安民
丁鹏
伏云发
Chen Li;Gong Anmin;Ding Peng;Fu Yunfa(School of Information Engineering and Automation,Kunming University of Science and Technology,Kunming,650500,China;Brain Cognition and Brain-Computer Intelligence Integration Group,Kunming University of Science and Technology,Kunming,650500,China;College of Information Engineering,Engineering University of PAP,Xi'an,710000,China)
出处
《南京大学学报（自然科学版）》
CAS
CSCD
北大核心
2022年第2期264-274,共11页
Journal of Nanjing University（Natural Science）
基金
国家自然科学基金(81470084,81771926,61763022,61463024,62006246)。
关键词
运动想象
脑机接口
欧式对齐
迁移学习
逻辑回归
motor imagery
brain-computer interface
Euclidean alignment
transfer learning
logistic regression
