Dementia is a chronic syndrome caused by brain cell death from neurodegenerative diseases or brain injuries. It is characterized by memory loss, personality changes, and impaired reasoning severe enough to affect daily life. The most common form is Alzheimer's disease. There are over 47 million cases worldwide currently, costing over $600 billion annually, and these numbers are expected to rise dramatically in coming decades. Symptoms vary depending on whether damage is cortical or subcortical but may include memory loss, confusion, problems with language and visual processing. Potential causes include neurodegenerative diseases, head injuries, infections, and substance abuse. Management focuses on drugs to improve symptoms as well as non-drug therapies like aromatherapy, music, and cognitive