Our QSMI had a incedent exactly like tuba's wife. Woke up in the field and thought he was a sgt again fighting in the Falklands.
It was put down at the time as post tramatic stress disorder. 2 months later it happened again but this time the whole of his left side was paralysed. CAT scan followed and he turned out to have a bleed point in his memory and motor function areas. He disappeared off to some mil hospital down south and we never saw him again.
I have had 3 grand parents who have dementia caused by stokes. Its a bloody awful way to go. With all of them they were found confused and dazed after a sleep. Short term memory gone. As it progresses the memory gets earlier and earlier. To the point that my granddad could quite happily talk about Dunkirk and france but didn't have a clue the war was finished.
In someways it was a relief when he passed away, if he had been a dog he would have been put down 4 years earlier.
Strangly enough he started speaking fluent French with a bloke in the nursing home. From what the family can tell he hadn't spoken french since the war and nobody knew he had even learned it when he was young.
The family has found that GP's (broad statement I know. But in general after speaking to other relatives of people) are crap at spotting this and managing it, you have to get a consultant who specialises in this area to do all the checks.
MJ