Transcranial Direct Current Stimulation in Patients With Disorders of Consciousness

Direct current was applied by a battery-driven constant current stimulator using saline-soaked surface sponge electrodes (7 3 5 cm) with the anode positioned over the left dorsolateral prefrontal cortex (F3 according to the 10-20 international system for EEG placement) and the cathode placed over the right supraorbital region. During real tDCS, the current was increased to 2 mA from the onset of stimulation and applied for 20 minutes.

For the sham condition(sham tDCS), the same electrode placement was used as in the stimulation condition, but the current was applied for only 5 seconds, and was then ramped down.