Fig. 2From: Electroencephalography-based endogenous brain–computer interface for online communication with a completely locked-in patienta The offline experimental paradigm. b The training paradigm of the online experiment. c The test paradigm of the online experiment. LMI, TMI, and MS indicate left-hand motor imagery, tongue motor imagery, and mental subtraction, respectively. The offline experiment and the training paradigm of the online experiment were similar except for the number of tasks. In the test paradigm of the online experiment, auditory feedback was provided in accordance with the online results of the participant’s EEG data analysisBack to article page