Figure 1

Outline of experimental procedures. In the pre-scan practice, subjects followed the set sequence 4-2-3-1-3-4-2 at 4 Hz for a 30-s period to learn the rhythm required in the following scan session. Each pre/post- training scan lasted 270 s, the 270 s run consisted of four 30-s task blocks of imagining the motor sequence alternated with five 30-s rest blocks. When PUSH was displayed on the screen, the participants were required to imagine the sequence 4-2-3-1-3-4-2 with their right hands at a self-paced rate of 4 Hz. When REST was displayed on the screen, the participants were instructed to relax. Each real-time fMRI training session lasted 450 s, during which time 30-s blocks of rest alternated with 30-s blocks of motor imagery with feedback, for a total of seven task blocks and eight rest blocks. During the rest blocks, a green “ + ” sign was presented on the screen; and during the task blocks, the green up arrow appeared on the screen along with the continually updated red curve. Questionnaire interview after scanning was to guarantee participants completed the motor imagery task well.