Inclusion Criteria:  Age 18-60 years old. Based on DSM5 Criteria: MDD with or without psychotic features.  Exclusion Criteria:  1 • Patients under 18 years old or above 60  2• Pregnant or lactating women.  3• Other current or past major psychiatric disorders  4• History or concurrent neurological disease(seizures) or prior head trauma with evidence of consequent cognitive impairment.  5• First degree family history of schizophrenia if the participant is less than 33 years old (mean age of onset of schizophrenia plus two standard deviations) to exclude possible prodromal phase of schizophrenia.  6• Unstable medical condition (i.e., any active illness that may affect the brain as blood dyscrasis, lymphomas, endocrinopathies, renal failure, chronic obstructive lung disease, systemic autoimmune disorders or Malignancy).  7• Patients being treated with steroids or hormonal therapy .  8• Current substances or alcohol use disorders (past diagnosis allowed if in remission for more than 6 months  9• Contraindications for MRI as:  Metal implants or paramagnetic objects contained within the body (including heart pacemaker or surgical prosthesis)  Claustrophobia significant enough to interfere with MRI  10• Refusal of informed consent