No definite cause they could come up with...
I was up about a hour when I realized something was wrong. I came downstairs dressed like a bum and asked Bruce why I was wearing those clothes...and said I didn't remember getting up. That was the start of it. I asked lots of questions over and over, so I'm told. Picked up a stack of birthday cards and asked why they were there. When DH told me I had just had a birthday, he said I asked him what month it was. We went to the neighbor's and she asked me some questions. I don't remember any of that.
We were in the car on the way to the hospital,..and I remember bits of the ride. That was about an hour and a half later...maybe. When we got to the hospital, I knew what was going on at the moment, but it would slip away. I answered all the questions, knew where I was and who was with me. Those memories have come back...sort of like stringing things together...frame by frame.
I can clearly remember the time from when I got up until I came downstairs and told DH something was wrong with me. But when I came downstairs, I didn't have that memory. A few hours later, I could tell the doctors exactly what I did that morning until I went upstairs and apparently dressed in mismatched clothes.
Maybe I'll remember, but maybe not.