For about 3 hours mum stares into space, doesn't talk or move then all of a sudden she's back like nothing happened. Any ideas?

I suspect she is taking a lot of psychotropics.. Take a good look at the med list.

My mom has done this several times. She's 90 dementia but otherwise in excellent physical health. They go off somewhere in there mind like a dream state then return like nothing happened and with no memory of the event or time loss. It hasn't hurt my mom although for mr sometimes scary. I've learned to ignore it and treat like nothing happened. It happens to my mom more on dreary dark days or when she has spent long periods alone.

Is she otherwise engaged in an activity or conversation when this happens or just when she's in a quiet place or alone?

thank you everyone for all your kind help
today i went in to give dad a break and she was on top form no staring into space or quite periods at all it was lovely to see, she still having conversations with no one but in good spirits bless her xx

If you just go to Google and search for "dementia staring into space" you'll see a lot of links. Evidently Lewy Body Dementia has that as one of the behaviors. Mayo Clinic has several links that reference staring into space as a normal part of dementia.

it has happens to my mum she is 81 with dementia she has been tested for seizures and was all clear and no infections I was told it is part of the dementia

To me it sounds like a seizure. I would definitely have her checked for that.

Angel

Thank you Vstefans ill ask dad to contact her specialist and let him know x

oh ok thank you very much Jessie, its really hard when you talk to her and theres just nothing at all, ive even pleaded with her saying mum its sharon sweatheart but just nothing x

It probably would be worth seeing a neurologist, it could be related to but a treatable part of her condition, e.g. a partial complex seizure and post-ictal state.

That does make all the difference. It is fairly common for a person to stare into space during the later stages of Alzheimer's. I don't think there is anything that can be done about it except to be there when she comes back.

sorry i should have said she has alzheimers and vascular dementia and was diagnosed 5/6 years ago all the medical team just says its part of the condition but i tried to google this and theres just nothing on this symptom at all

It sounds like she needs to see her doctor. Let the doctor know about the symptoms. Something is going on. Let us know what the doctor says. He/she will probably do some tests, which may provide answers you are looking for.