A randomized, sham-controlled, double-blinded and parallel group trial (12 therapeutic sessions) with optimal protocol (defined in phase 1) and sham tDCS will be conducted to evaluated electrical cortical activity and pain control, number of migraine attacks and quality of life of migraine patients. Electrical cortical activity will be assessed through: (i) motor evoked potential (MEP); (ii) motor threshold (MT); (iii) short interval intracortical inhibition (SICI); (iv) intracortical facilitation (ICF); (v) phosphene threshold (PT) and (vi) visual evoked-potential (VEP-habituation). Clinical outcomes will be evaluated through: (i) headache diary; (ii) visual analog scale (VAS); (iii) Migrainde disability assessment (MIDAS); (iv) Headache Impact Test (HIT-6) and (v) World Health Organization quality of life assessment instrument (WHOQOL BREF).
