Dementia is a word used to describe a loss of memory, language, problem-solving, and other thinking abilities that is severe enough to affect daily life. The most common cause of dementia is Alzheimer's disease. Dementia is not a single disease; it's an umbrella term that encompasses a wide range of medical problems, including Alzheimer's disease, similar to heart disease. Abnormal brain alterations create the disorders included under the umbrella term "dementia." These alterations cause a deterioration in thinking abilities, also known as cognitive capacities, that is severe enough to interfere with daily life and independence. They also have an impact on one's conduct, emotions, and relationships.