Research has showed that Dementia is the loss of cognitive functioning — thinking, remembering, and reasoning — to such an extent that it interferes with a person's daily life and activities. it is clearly state that people with dementia cannot control their emotions, and their personalities may change quit alright.
Dementia is more common as people grow older (about one-third of all people age 85 or older may have some form of dementia) but it is not a normal part of aging. Many people live into their 90s and beyond without any signs of dementia.
We have several forms of dementia, one of which is Alzheimer’s disease. A person’s symptoms can vary depending on the type.