My Dad had Alzheimers, and I really noticed that during his Mental decline, that his eyes "changed". Pupils were dilated, and he became "squinty", and finally - there was "nothing there". Like his soul had left his body. I see a similar progression with Trump - it's "in the eyes".
In his recent meeting with the foreign heads of state, he started talking about one that was sitting directly in front of him and he was looking around and didn't even see him. There wasn't more than 6 people in the group! Talk about stupid!!!!
That's how Daddy Fred went out. If he has any cognition left that's scaring more shit out of him than isual.