title: An N200 speller integrating the spatial profile for the detection of the non-control state.
abstract: The N200 speller is a recently developed non-flashing visual brain-computer interface (BCI) paradigm utilizing the overt attention modulation effects on motion-onset visual evoked potentials (mVEP). In this study, a novel algorithm is proposed and applied in an online N200 speller. The proposed algorithm integrates the spatial information of the speller matrix to provide a more precise description of the mVEP response patterns, which is defined as the 'spatial profile'. More importantly, only control state data are used in the algorithm to train a classifier that nonetheless can detect the non-control state effectively. Compared to an algorithm with similar structure but not using the spatial profile information, the proposed algorithm shows significantly higher performance for the recognition of the non-control state while achieving a comparable performance for classifying different control states. Offline and online classification results show that the proposed N200 speller is a promising step toward a practical, online non-flashing BCI system for daily use.
authors.affiliation: Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, People's Republic of China.
authors.forename: Dan
authors.initials: D
authors.lastname: Zhang
authors.forename: Huaying
authors.initials: H
authors.lastname: Song
authors.forename: Honglai
authors.initials: H
authors.lastname: Xu
authors.forename: Wei
authors.initials: W
authors.lastname: Wu
authors.forename: Shangkai
authors.initials: S
authors.lastname: Gao
authors.forename: Bo
authors.initials: B
authors.lastname: Hong
mesh_terms: D000328:Adult; D000465:Algorithms; D001185:Artificial Intelligence; D001921:Brain / Q000502:physiology*; D004569:Electroencephalography; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology; D009862:Online Systems; D010775:Photic Stimulation; D012372:ROC Curve; D015203:Reproducibility of Results; D014584:User-Computer Interface; D055815:Young Adult