The purpose of this study is investigation of the effectiveness of memantine on cognitive performance in patients treated with ECT. This study is a double-blind placebo- controlled clinical trial. The population of the study is patients that candidate for ECT who are between 18 and 60 years of age and 4 to 12 sessions of ECT that agree with informed consent and do not have dependency or abuse of alcohol or drugs (except nicotine or caffeine) within 3 months prior admission, do not have contraindications for Memantine, seizures, delirium, dementia, do not have cognitive impairment, do not be in lactation or pregnancy phase, and no history of taking Memantine from 3 months prior to admission and drug that have interaction with Memantine. Sample sixe has been (in both intervention and control groups) evaluated 20 cases. Intervention in this study is Memantine or placebo in intervention and control groups 48 hours before ECT until 24 hours after completion of ECT course, which is used with 10 mg two times a day . outcome variables of the study are cognitive status, short-term memory, concentration and precision that will be checked with mini mental state examination scores(MMSE) and digit span test figures (one of the subtests of the Wechsler).