<(O.o)> Just reading about our brains and memory.
One incident was someone in a motorcycle accident and had retrograde and anterograde amnesia. Which the individual had memories on facts and skills but couldn't remember anything before the accident nor be able to acquire new memories as things were happening.
So to this one person, everything was just happening, couldn't see themselves in future events and just saw blackness.
It was just a report, but really once again the idea on how our brains are wired came up in another medical report. It's the way our brains get crossed wired and deja vu happens. It's when you brain mistakenly takes present events and make you think they were in your past. It's like adding a signature on a file when you last saved it on your computer, but let's say it's been opened for years and you just decided to hit save and the time signature is all off.
Actually it would probably be more like your computer crashed and then a crap load of back-up saves in Excel opened and you don't know what is your current file due to auto-backups.
The Abyss
An article by the late renowned neurologist & author, Oliver Sacks. It's a case similar to the one you described (I suspect it's the same person): a musician who got into a car accident with his wife. His wife sustained minor injuries, but his was serious (brain injury), and eventually he developed a severe form of retrograde amnesia. He also couldn't retain any new memories about his current life (I believe that happened later on), and would lose them in a matter of minutes, days, or weeks (IIRC). He might go into the kitchen one moment to get something, only to walk out of it the next moment, wondering where he was, what he was doing there, and even asking his wife who the heck she was, just like a soft reboot. He still preserved his musical skills, and could play music from memory. His wife was the one giving that account about that period of his life. She stood by him despite the whole thing being very painful for her. A really sad story.
My memory is hazy on the details, sorry. I read about it a while ago.