My husband is having problems with sleeping too long and memory problems as a result. We have had an Mir of his brain and it looks fine, his carotid arteries are fine. It is unusual for him to sleep 11 to 13 hours at a time. This only happens once every three to six months. When he wakes up from these episodes he has mild to severe amnesia. He can always know who he is and can usually remember the far past, but does not remember where he works, our relationship, his grandkids names and ages. I am worried that it is very low blood pressure causing this but don't know for sure and can not get him to go to a doctor.