When I'd take Mom to the Doc he'd say that we were seeing the symptoms of dementia, and I felt fortunate that it wasn't Alzheimer's, "only" dementia. As time went on I learned more, and found that dementia, in all of it's many forms is the big, bad monster, and Alzheimer's is simply the most common version that has some specific symptoms that were first quantified by Dr. Alois Alzheimer in 1906. When the Doc mentions "dementia" he's identified the monster, and the monster comes in many forms. As time has passed I'm pretty sure that my Dad had some degree of dementia too, but he was practiced at hiding it.