M37. THERAPEUTIC EFFECT OF TRANSCRANIAL DIRECT CURRENT STIMULATION ON WORKING MEMORY OF PATIENTS WITH RECENT ONSET SCHIZOPHRENIA: A RANDOMIZED CONTROLLED STUDY

BACKGROUND: Working memory is impaired in many patients with psychotic disorder and influence their daily living. This study aimed to evaluate therapeutic effect of transcranial direct current stimulation (tDCS) on working memory of patients with recent onset schizophrenia. METHODS: 40 patients with schizophrenia randomized to either 6 sessions of add-on active (2 mA, 20min) or sham tDCS (anode: left DLPFC/F3; cathode: right supraorbital/F4, duration of 30 minutes and 72 hours in between). Patients with predominant negative symptoms were excluded. Primary outcome was improvement of working memory performance on letter-number sequencing test and secondary outcome was reduction in Positive and Negative Syndrome Scale (PANSS). RESULTS: Majority of patients (90%) were male. Mean age was 34.12 (±11.20) ranging from 27 to 59 years. Mean score of PANSS was 9.8±2.1 in negative, 17.4±4.0 in positive and 19.2±3.2 in general symptoms. Cognitive performance of patients receiving tDCS improved significantly (7.7±2.3 to 10.3±1.7, p=0.001) compared to the sham group (8.9±3.5 to 9.1±2.4). PANSS score did not change significantly and had the same trend in the two groups. DISCUSSION: The results of the present study indicate that prefrontal tDCS may be a promising intervention for cognitive rehabilitation in patients with recent onset schizophrenia with prominent positive symptoms.