Finally, other variables influencebaseline cortical excitability such as gender,111age,112andsmoking.113Hence, the same amount of current is likely tohavenonuniformeffectsinsubjectswithdifferentconditions.For instance, one study showed that low (25 mg) and high(200 mg) doses of l-dopa abolished tDCS-induced effectson cortical excitability, whereas an intermediate (100 mg)dosage increased inhibitor