Fig. 1

Illustration of three different MI paradigms. This diagram is presented here to provide a general knowledge of the difference among the three MI paradigms. a MI tasks paradigm; b two-class control paradigm (also named 1-D cursor control); c four-class control paradigm (also named 2-D cursor control). Three experimental stages presented in each paradigm are rest stage, preparation stage and execution stage. In the execution stage of paradigms b and c, eyes are open, with real-time visual feedback; whereas in execution stage of paradigm a, eyes are closed without visual feedback