Navigated ?TMS in Treatment-resistant Schizophrenia (nTMS_NS)

Since 1990s, stimulation of prefrontal cortex (PFC) has shown therapeutic effects on auditory hallucinations as well as negative symptoms of schizophrenia. However, previous studies have reported mixed or negative results. Majority of the repetitive transcranial magnetic stimulation (rTMS) studies to date has set the target of cortical stimulation based on scalp site. Recently introduced method, navigated transcranial magnetic stimulation (nTMS) integrates the individual MRI data, and thus allows more precise targeting on brain cortical regions enhancing the efficacy of rTMS. Previous EEG studies have suggested reduced alpha band activity in patients with schizophrenia. Some recent studies using alpha (?) EEG guided TMS for treating positive and negative symptoms of schizophrenia have demonstrated promising results. The aim of the study is to investigate the efficacy of navigated individualized ?TMS in treatment-resistant patients with schizophrenia. Approximately fifty patients with DSM-IV schizophrenia will be enrolled in this randomized, double-blind, sham-controlled study. The patients will receive 13 - 15 session of ?TMS to the left dorsolateral prefrontal cortex (DLPFC), as adjunctive therapy, for 3 weeks. We assess patients via the Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression (CGI) and neurocognitive test battery at baseline, 5 days after and 3 months after treatment. Serum and plasma levels of brain derived neurotrophic factor (BDNF) are assayed at pre and post treatment weeks.