Abstract
The electroencephalogram (EEG) induced by steady-state visual evoked potential (SSVEP) will contain background noise. Most existing research on this problem uses signal-processing methods to enhance the EEG. The purpose of this paper is to explore another method that can be used to enhance the EEG. We creatively combined motion stimuli with light-flashing stimuli and designed a paradigm in which motion and light-flashing simultaneously will stimulate with the same frequency; this is called multi-source co-frequency stimulus. To avoid the direct stimulus of light-flashing in the human eye and ensure that the composite paradigm provided adequate comfort, the light-flashing pattern was presented in a ring form and the motion stimulus was presented in the center of that ring. Our hypothesis is that when the motion and the light-flashing are simultaneously stimulated with the same frequency, the EEG they induce will be superimposed in some way, and this will enhance the EEG. The multi-source co-frequency stimulus was found to achieve a higher signal-to-noise ratio (SNR), better accuracy, and a higher information transmission rate (ITR) than single stimulus. The experimental results showed that it is feasible to use the method proposed in this study to enhance the EEG.
Funding source: National Natural Science Foundation of China
Award Identifier / Grant number: 51775415
Acknowledgments
This research was supported by National Natural Science Foundation of China (NSFC) (no. 51775415). We want to thank the subjects for participating in these experiments and anonymous reviewers for their helpful comments.
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Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Competing interests: Authors state no conflict of interest.
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Informed consent: Informed consent was obtained from all individuals included in this study.
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Ethics approval and consent to participate: The subjects provided informed written consent, in accordance with the protocol approved by the institutional review board of Xi’an Jiaotong University.
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Supplementary Material
The online version of this article offers supplementary material https://doi.org/10.1515/bmt-2019-0262.
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