Transcranial direct current stimulation was applied for 15 minutes on 10 consecutive days by using a 1 mA current and 7 cm × 5 cm electrodes, resulting in a current density of 0.029 mA/cm2. The medication doses (5 mg of haloperidol and 20 mg of olanzapine) remained the same 4 weeks before and during the patient's intervention. Before and after tDCS, we measured arterial spin labeling, a noninvasive MR technique that provides a direct quantitative measure of cerebral blood flow (CBF). Arterial spin labeling has been successfully used to measure the difference and changes in regional CBF between healthy individuals and schizophrenia patients experiencing formal thought disorders (5). Clinical assessments showed improvements in our patient's scores on the Hallucination Change Scale (pre-tDCS score=10; post-tDCS score=4), the Positive and Negative Syndrome Scale (pre-tDCS score=61; post-tDCS score=50), and the Psychotic Symptom Rating Scale (pre-tDCS score=51; post-tDCS score=43). The decrease in regional CBF indicated that the intervention had a specific neurobiological effect (Figure 1). At follow-up investigation 6 weeks after the tDCS intervention, our patient's clinical improvement was maintained.