Fig. 3

Experimental stimuli. (a) General setup of the motor task. (b) The participants started with the stylus at the starting point (the lower-middle target). After remaining there for 500 ms, (c) the center target turned red and one of the targets turned green, according to the current location in the sequence 4-1-3-2-5. After moving to and remaining at the target for 500 ms, the screen returned to (b), and the participants needed to lift the pen and return it to the starting point. Note that in this figure, for clarity, the targets and numbers are shown 3 times their relative size compared to those shown in the experiment. (d) Day 1 included pretest, test that started after two min of the appropriate stimulation and lasted six min, and posttest. Day 2 consisted of a retention test. Each of the tests (pretest, during stimulation, posttest and retention test) consisted of two blocks of 6 sequences (30 reaching movements within a block), with a 30 s break between blocks