Seeing famous actors e.g. Robin Williams, and Bruce Willis suffering from dementia made me wonder in later stages do the people still aware of death? We all know death because we know the process we learn from or it’s just that we instinctively aware of it?
I’m sure it varies from person to person and disease to disease.
About three years ago my brother died of brain cancer and I was there helping him through the whole process of decline and death. He was definitely aware he was dying earlier on, of course, when the tumor’s effects were mild. But in his final days he just kind of shut down bit by bit. He seemed to be unaware of some of the degradation that was happening to his mind - he would lose specific words, for example, substituting random words in their place, but he was unaware this was happening even when we told him about it. One of the surgeries ended up taking out a quarter of his visual field but we only knew that because they explicitly checked - he didn’t seem to be aware that he couldn’t see stuff in that quadrant any more. So I suppose in his case the progression was fairly “merciful.”
If you’re dealing with a specific situation here, I’d recommend asking one of the doctors involved. I’m sure they’ll have some knowledge more specific to it.