Facts about Alzheimer's DiseaseAlzheimer’s disease, also known as dementia, is a severe brain disorder that affects a person’s ability to live a regular life. Alzheimer’s disease affects areas of the brain such as thought, language, and most importantly memory. When Alzheimer’s disease begins in the human body, the nerve cells begin to die off in areas of the brain that are extremely imperative to mental functioning and memory power. To this day, scientists still have no conclusion to what the causes of Alzheimer’s disease are. There is most likely more than one single cause for Alzheimer’s disease, and everyone if affected differently by it.