Just to add, I'd say generally speaking, my mum can see and hear pretty well. But I am learning to speak to her in 2 or 3 word sentences. Anything longer and by the time I've finished what I'm saying she has forgotten the first bit. A sentence doesn't make sense until you've listened to it all and retained it - mum can't do that. I no longer say, 'Look at that big black cloud - looks like it's going to pour down! Did you hear the thunder last night?' Now I have to break it down: 'Look at that!' i.e. get her attention first. She would ask, 'What?' Then I can continue, 'Look out there! (Point out the window) Up in the sky! (Short pause till she looks the right way.) A huge black cloud!' Then when she has focussed on it I can add, 'Do you think it's going to rain?' Unless I do it like that she just won't understand.
I only discovered this because I was worried about her hearing. Everything I said she would say, 'Pardon?' But it wasn't because she hadn't heard, she just hadn't been able to process what I said to her, so short sentences, with full explanations, are the only thing that work now.
With vision, she will often look out the window and misinterpret what she sees. 'What's that man doing on that roof?' No man there, just a dark shadow. Or, 'What's that black thing on the bed?' This was actually my jacket which I had taken off and put there just a couple of minutes before. She just didn't recognise what she was seeing. I also escorted her to the bathroom as she'd wet herself. I told her to sit on the loo and she asked 'where is it?' She was looking directly at it.
These things have got worse in the 2 and a half years she's been in the CH. I first noticed it early on when she swore blind there was no shower in her en-suite. There is, but it's a wet room so there is no shower enclosure. It just doesn't look like a shower to her.
It's so sad to watch the decline. But I admit I am totally fascinated by the brain and its complexities!