A 70 yr old man presents with 10 prosopagnosia loss of memory, 3rd person hallucination since 1 month. On examination deep Tendon reflexes are increased, minimental examination score is 20/30. What is most likely diagnosis:

C i.e. Alzheimer's disease Duration of 1 month only, is enough to rule out schizophrenia, in which duration should be at least 6 months In psychiatric disorders like schizophrenia & psychosis, there may never be organic symptoms like increased tendon reflexes. Features of Alzheimer dementia are Memory impairment without impairment of consciousnessQ AgnosognosiaQ (Unware of his problem) Prosopangosia (difficulty in identifying known faces) Focal neurological signs (ex assymetrical hyper-reflexia or weakness)Q Primitive reflexes (ex grasp, snout, suck, palmo-mental, & tonic foot reflexes) Frontal lobe signs Aphasia (language disturbance) Apraxia (impaired ability to carry out motor activities despite intact motor function) Agnosia (failure to recognize or identify objects despite intact sensory function) Disturbance in executive functioning (i.e. planning, organizing, sequencing, abstracting)