Noise robustness analysis of sparse representation based classification method for non-stationary EEG signal classification. (August 2015)

• Record Type: Journal Article
• Authors: Shin, Younghak; Lee, Seungchan; Ahn, Minkyu; Cho, Hohyun; Jun, Sung Chan; Lee, Heung-No
• Is Part Of: Biomedical signal processing and control. Volume 21(2015)
• Page Start: 8
• Page End: 18
• Publication Date: 2015-08
• Subjects: Brain–computer interface (BCI) -- Electroencephalogram (EEG) -- Sparse representation based classification (SRC) -- Common spatial pattern (CSP) -- Non-stationarity; Signal processing -- Periodicals; Biomedical engineering -- Periodicals; Signal Processing, Computer-Assisted -- Periodicals; Image Processing, Computer-Assisted -- Periodicals; Biomedical Engineering -- Periodicals; 610.28
• DOI: 10.1016/j.bspc.2015.05.007
• Languages: English
• ISSNs: 1746-8094

Abstract

Highlights: Evaluation of noise robustness of sparse representation based classification (SRC) method. Generation of new noisy test signals by adding two noise sources into the EEG test signals. Demonstration of the improved classification accuracy of the SRC for noisy test signals and online dataset. Illustration of the suitability of the SRC for non-stationary EEG signal classification. Abstract: In the electroencephalogram (EEG)-based brain–computer interface (BCI) systems, classification is an important signal processing step to control external devices using brain activity. However, scalp-recorded EEG signals have inherent non-stationary characteristics; thus, the classification performance is deteriorated by changing the background activity of the EEG during the BCI experiment. Recently, the sparse representation based classification (SRC) method has shown a robust classification performance in many pattern recognition fields including BCI. In this study, we aim to analyze noise robustness of the SRC method to evaluate the capability of the SRC for non-stationary EEG signal classification. For this purpose, we generate noisy test signals by adding a noise source such as random Gaussian and scalp-recorded background noise into the original motor imagery based EEG signals. Using the noisy test signals and real online-experimental dataset, we compare the classification performance of the SRC and support vector machine (SVM). Furthermore, we analyze the unique classification mechanism of the SRC. We observed that the SRC method provided better classification accuracy and noise robustness compared with the SVM method. In addition, the SRC has an inherent adaptive classification mechanism that makes it suitable for time-varying EEG signal classification for online BCI systems.