Effects of Different Intensities of Bilateral- and Cathodal Transcranial Direct Current Stimulation in Healthy Individuals

This study will separate study to investigate the effects of 1 mA, 1.5 mA, and 2 mA of 1) bilateral- and 2) cathodal tDCS on cortical activity and motor learning in healthy individuals

Inclusion Criteria: * 1\. Age 18-29 years old * 2\. Righ-hand dominant according to the Edinburgh handedness inventory * 3\. No injury to both upper and lower limb for the past 6 months Exclusion Criteria: * 1\. Presence of any neurological disorders * 2\. Presence of metal implantation, intracranial shunt, cochlear implantation, or cardiac pacemakers * 3\. Presence of opened wound or infectious wound around scalp * 4\. History of epilepsy or any neurological antecedent or unstable condition which can lead to seizure * 5\. Body mass index (BMI) \> 30 kg/m2 * 6\. Received hormonal treatment and/or drugs that increase sleepiness and affect movement control * 7\. Ischemic heart disease and peripheral vascular ischemia * 8\. Last stage of kidney disease and liver disease