Dementia is a syndrome characterised by a chronic or progressive brain disorder in which numerous higher cortical functions, such as memory, thinking, direction, understanding, computation, learning ability, language, and judgement, are disrupted. The state of consciousness is clear. Dementia primarily affects the elderly; just 2% of cases begin before the age of 65. After that, every five years of age increases the incidence by a factor of two. Dementia is one of the most common causes of later-life disability. In the elderly, neurodegenerative processes affect the brain, resulting in gradual, incapacitating cognitive, behavioral, and motor dysfunctions that eventually lead to dementia. The presence of neurological symptoms, which could act as early indicators of dementia and predictors of mortality, is likely to precede fully evident dementia.