People can be conscious and not remember. Alzheimer patients are a clear example. A model of memory (there are more) says that we form "traces" of events by tr

People can be conscious and not remember. Alzheimer patients are a clear example. A model of memory (there are more) says that we form "traces" of events by transferring from short-term to long-term memory, but that these traces need to be fixed to stay memories. This process can go wrong in many ways, but traces can also be forgotten or replaced. E.g., when I go to bed, I know/remember that I've locked the front door, but I can't remember that I locked it yesterday. I suppose I did, but I have little to no recollection of it. In computer metaphors, it's as if this event only has a trace to a single place in memory.