학술논문

Application of Covariate Shift Adaptation Techniques in Brain–Computer Interfaces
Document Type
Periodical
Source
IEEE Transactions on Biomedical Engineering IEEE Trans. Biomed. Eng. Biomedical Engineering, IEEE Transactions on. 57(6):1318-1324 Jun, 2010
Subject
Bioengineering
Computing and Processing
Components, Circuits, Devices and Systems
Communication, Networking and Broadcast Technologies
Testing
Linear discriminant analysis
Adaptive systems
Electroencephalography
Educational technology
Fatigue
Electrodes
Bagging
Computational intelligence
Impedance
brain–computer interface (BCI)
covariate shift adaptation
Language
ISSN
0018-9294
1558-2531
Abstract
A phenomenon often found in session-to-session transfers of brain–computer interfaces (BCIs) is nonstationarity. It can be caused by fatigue and changing attention level of the user, differing electrode placements, varying impedances, among other reasons. Covariate shift adaptation is an effective method that can adapt to the testing sessions without the need for labeling the testing session data. The method was applied on a BCI Competition III dataset. Results showed that covariate shift adaptation compares favorably with methods used in the BCI competition in coping with nonstationarities. Specifically, bagging combined with covariate shift helped to increase stability, when applied to the competition dataset. An online experiment also proved the effectiveness of bagged-covariate shift method. Thus, it can be summarized that covariate shift adaptation is helpful to realize adaptive BCI systems.