With this illness, anything is possible. No frank mania--just hypo?

That is a ton of episodes. It si certainly conceivable that that many hours hyperstimulated could result in some hippocampus and prefrontal memory-type issues, in my opinion. But as others state, the issue always arises as to what is illness-related and what is med-related. I have no clue how to address that scientifically without followign closely a large group of patients on no meds, which is never going to happen.

My memory is just shot, short-term, anyway. Long-term is pretty solid, still.

Are you doing any memory exercises or work? It has been shown to help.