Neghabi Mehrnoosh, Marateb Hamid Reza, Mahnam Amin
Department of Biomedical Engineering, Faculty of Engineering, University of Isfahan, Isfahan, Iran.
Basic Clin Neurosci. 2019 May-Jun;10(3):245-256. doi: 10.32598/bcn.9.10.200. Epub 2019 May 1.
Brain-Computer Interface (BCI) systems provide a communication pathway between users and systems. BCI systems based on Steady-State Visually Evoked Potentials (SSVEP) are widely used in recent decades. Different feature extraction methods have been introduced in the literature to estimate SSVEP responses to BCI applications.
In this study, the new algorithms, including Canonical Correlation Analysis (CCA), Least Absolute Shrinkage and Selection Operator (LASSO), L1-regularized Multi-way CCA (L1-MCCA), Multi-set CCA (MsetCCA), Common Feature Analysis (CFA), and Multiple Logistic Regression (MLR) are compared using proper statistical methods to determine which one has better performance with the least number of EEG electrodes.
It was found that MLR, MsetCCA, and CFA algorithms provided the highest performances and significantly outperformed CCA, LASSO, and L1-MCCA algorithms when using 8 EEG channels. However, when using only 1 or 2 EEG channels d, CFA method provided the highest F-scores. This algorithm not only outperformed MLR and MsetCCA when applied on different electrode montages but also provided the fastest computation time on the test set.
Although MLR method has already demonstrated to have higher performance in comparison with other frequency recognition algorithms, this study showed that in a practical SSVEP-based BCI system with 1 or 2 EEG channels and short-time windows, CFA method outperforms other algorithms. Therefore, it is proposed that CFA algorithm is a promising choice for the expansion of practical SSVEP-based BCI systems.
脑机接口(BCI)系统为用户和系统之间提供了一条通信途径。基于稳态视觉诱发电位(SSVEP)的BCI系统在近几十年中得到了广泛应用。文献中已经介绍了不同的特征提取方法来估计BCI应用中的SSVEP响应。
在本研究中,使用适当的统计方法对包括典型相关分析(CCA)、最小绝对收缩和选择算子(LASSO)、L1正则化多路CCA(L1-MCCA)、多集CCA(MsetCCA)、共同特征分析(CFA)和多元逻辑回归(MLR)在内的新算法进行比较,以确定哪种算法在使用最少数量的脑电图电极时具有更好的性能。
发现MLR、MsetCCA和CFA算法具有最高的性能,并且在使用8个脑电图通道时显著优于CCA、LASSO和L1-MCCA算法。然而,当仅使用1个或2个脑电图通道时,CFA方法提供了最高的F分数。该算法不仅在应用于不同电极组合时优于MLR和MsetCCA,而且在测试集上提供了最快的计算时间。
尽管MLR方法已经证明与其他频率识别算法相比具有更高的性能,但本研究表明,在具有1个或2个脑电图通道和短时间窗口的基于SSVEP的实际BCI系统中,CFA方法优于其他算法。因此,建议CFA算法是扩展基于SSVEP的实际BCI系统的一个有前途的选择。