You should read this https://www.nytimes.com/2017/11/02/magazine/why-was-their-brothers-memory-and-behavior-so-strange.html https://www.nytimes.com/2017/11/02/

You should read this https://www.nytimes.com/2017/11/02/magazine/why-was-their-brothers-memory-and-behavior-so-strange.html https://www.nytimes.com/2017/11/02/magazine/why-was-their-br... IIRC "dementia" is literally just a description of symptoms. The real truth seems to be that we just barely have the slightest fucking clue most of the time.