Figure 2.

Experimental setup and protocol. (A) During the experiment, the subjects were seated comfortably in a chair with armrests at 60 (±5) cm in front of a 21-inch LCD monitor. (B) EEG signals were measured using brainwave collection equipment (BrainAmp, BrainProducts GmbH, Germany) and data recorders (BrainVision, BrainProducts GmbH, Germany). (C) In the experimental paradigm, for all blocks, the first 3 s of each trial began with a fixation cross that appeared at the center of the monitor to prepare subjects for the MI task. Afterward, the subject performed the imagery task using the appropriate hand for 4 s when a right or left arrow appeared as a visual cue. After each task, the screen remained blank for 6 s. The given data set provides only 4 s MI tasks.