Hi Dave, I very strongly suspect he's developing agnosia, which caused
by brain damage. As you know, as AD progresses, the person starts to
get lost even in familiar areas, and starts to have trouble
recognizing people. Their ability to recognize objects, faces, places
etc. starts to disappear. Sometimes, they think the people they love
or the home they live in have been somehow replaced with artful
copies. Like...it looks like her, but it is an imposter,...and it is
sort of like my house, but its a diabolical copy. In the early stages,
things just don't look quite right.

Imagine living in a world, where everything looks odd to you. Now
layer on top of that your loss of short term memory, where you aren't
really sure how you got where you are, and can't get a grip on what is
going to happen next. Your sense of time is all distorted. Have you
been here five minutes or five days? You are surrounded by things that
are starting to make no sense to you. Everything is starting to be
swirling jumble you can't get your bearings in.

That would make you feel disconnected from reality - you'd feel
wierdly disconnected from what was going on - everything would be
disorienting.

If you want the honest truth, I don't think there is anything they can
do about it. Its a function of a damaged brain.
Here is a description of different forms of agnosia. http://en.wikipedia.org/wiki/Agnosia
When  you read other descriptions of agnosia, they sometimes make the
error of  describing this as rare. Its not rare at all across the
population, since its extremely common in almost all dementias, and as
we all know, something like 50% us will have some sort of dementia if
we survive into our mid 80's - and we'll also have developed at least
one kind of agnosia. It's only "rare" in younger healthy adults.

M.