INTRODUCTION: Patients with schizophrenia elicit cognitive decline from the early phase of the illness. Mismatch negativity (MMN) has been shown to be associated with cognitive function. We investigated the current source density of duration mismatch negativity (dMMN). by using low-resolution brain electromagnetic tomography (LORETA). https://www.roamingfreesims.com/product-category/led-dali-invertor/