I have often wondered why my Alzheimer's suffering husband seems to have trouble seeing certain things even though he had cataract surgery a few years ago.
In one of the comments someone said Alzheimer's sufferers cannot see white. I had never heard of this and would like more discussion.
Bathrooms done in shades of white, with a white floor, white walls and a white toilet can be particularly difficult. The toilet effectively disappears. I read if one buys a dark color toilet seat, it can make it easier to find. In the shower white grab bars on one tile are harder to find. Put a bright color rubber mat in the bottom of the bathtub.
My Mom doesn't have Alzheimer's/Dementia but she has macular generation... I gave Dad a bright red vest to wear to make it easier for Mom to see where he is.