Repeated stimulation of the posterior parietal cortex in patients in minimally conscious state: a sham-controlled randomized clinical trial

•tDCS is a simple and safe technique that has shown promising results in MCS patients.•tDCS applied over the posterior parietal cortex improved signs of consciousness in 27% of the stimulated patients.•The effects were only transient and patients returned to baseline when reassessed at 5-day follow-up.•Acute patients responded better than chronic patients to tDCS.•Localization and extend of the brain lesions might affect tDCS effects.