Fig. 6

Results of the online experiment and test–retest reliability of the BCI system. a Results of the online experiment. RG was used as the classification algorithm. The number of electrodes was 19. The Y axis indicates the averaged online classification accuracies for each online run. The red horizontal dotted line indicates the level of chance. Note that the chance level is 70% when the number of trials is 20 and the confidence level is 99% [52] (b) Test–retest reliability of the BCI system. The Y axis indicates average classification accuracies for each training dataset