Sparse Logistic Regression-Based EEG Channel Optimization Algorithm for Improved Universality across Participants

Bioengineering (Basel). 2023 May 31;10(6):664. doi: 10.3390/bioengineering10060664.

Abstract

Electroencephalogram (EEG) channel optimization can reduce redundant information and improve EEG decoding accuracy by selecting the most informative channels. This article aims to investigate the universality regarding EEG channel optimization in terms of how well the selected EEG channels can be generalized to different participants. In particular, this study proposes a sparse logistic regression (SLR)-based EEG channel optimization algorithm using a non-zero model parameter ranking method. The proposed channel optimization algorithm was evaluated in both individual analysis and group analysis using the raw EEG data, compared with the conventional channel selection method based on the correlation coefficients (CCS). The experimental results demonstrate that the SLR-based EEG channel optimization algorithm not only filters out most redundant channels (filters 75-96.9% of channels) with a 1.65-5.1% increase in decoding accuracy, but it can also achieve a satisfactory level of decoding accuracy in the group analysis by employing only a few (2-15) common EEG electrodes, even for different participants. The proposed channel optimization algorithm can realize better universality for EEG decoding, which can reduce the burden of EEG data acquisition and enhance the real-world application of EEG-based brain-computer interface (BCI).

Keywords: brain–computer interface; channel optimization; electroencephalogram; sparse logistic regression.

Grants and funding

This work was supported in part by the Japan Society for the Promotion of Science (JSPS) KAKENHI under Grant 19H05728, in part by the Japan Science and Technology Agency (JST) Support for the Pioneering Research Initiated by Next Generation (SPRING) under Grant JPMJSP2106.