HD-tDCS Combined With Circadian Rhythm Reconstruction and Micro Expression Changes on Consciousness Recovery in Patients With Chronic Disturbance of Consciousness

Participants assigned to the melatonin group were given a 3-mg fast-release oral dose of melatonin administered at approximately 21:00

Participants in this group were treated according to a protocol identical to those receiving active medication at approximately 21:00. For the sham tDCS groups, the same stimulation parameters were employed, except that the stimulator had a built-in placebo mode; when it was activated, two ramp fade-in/fade-out periods in the beginning and the end of sham stimulation mimicked the somatosensory artifact of real tDCS

Direct current was applied using a battery-driven constant-current stimulator through saline-soaked surface sponge electrodes (7cm×5cm) with the anode placed over the left DLPFC (F3 according to the 10-20 international EEG system) and the reference cathode placed over the right supraorbital region (Fp2). During real tDCS, the current was increased to 2 mA from the onset of stimulation and applied for 20 minutes