“Non-stationarities are ubiquitous in EEG signals. They are especially apparent in the use of EEG-based brain-computer interfaces (BCIs): (a) in the differences between the initial calibration measurement and the online operation of a BCI, or (b) caused by changes in the subject’s brain processes during an experiment (e.g. due to fatigue, change of task involvement, etc).”
In this paper, the authors quantify systematic evidence of statistical differences in data recorded during offline and online sessions. The authors also propose novel techniques of investigating and visualizing data distributions, which are particularly useful for the analysis of (non-)stationarities.
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