2.4. tDCS Intervention
CORTEX
During the tDCS intervention (Neuroconn, Germany), two electrodes (5 × 7 cm) soaked in saline solution were applied to the scalp of the patients, applying a low-amplitude direct current (2 mA). The location of the primary motor cortex (M1) of the non-lesioned and lesioned hemispheres was based on the international 10/20 positioning system electroencephalogram. For the anodal tDCS group, the electrode was placed in the motor area ipsilateral to the lesioned hemisphere at points C3 or C4 (according to the 10/20 reference system), and the cathode was positioned over the contralateral supraorbital area. In the cathodal tDCS group, the cathode was positioned over the C3 or C4 motor area of the non-lesioned hemisphere, and the anode over the supraorbital area ipsilateral to the lesion. The sham tDCS group was subjected to the same procedure as the anodal tDCS group. The stimulation protocol lasted 20 min with a ramp up and down of 10 s, except for the sham tDCS group, which lasted 30 s to achieve a good level of blinding [