Could you explain what is dementia and some common symptoms that indicate people have it?

Cognitive decline: Losses in mental functioning beyond normal aging - often short term memory may come first but other abilities may also be affected - planning, judgement, personality, temper, etc. There are several types with different profiles and they can progress fast, slowly or not at all. Alzheimer's, vascular(stroke), trauma, hiv/aids, lewey body are some very distinct types you might have heard of. Be well.