If you get complete amnesia, did you die? If you are braindead, are you alive?
Are you your body or a collection of memories that inform a consciousness? Are you more than both or something else entirely? A soul perhaps that like dark matter is yet to be detected but has been calculated by the collective experiences the majority of humans throughout our history? Like a radio signal propagating reality your body just happened to be tuned to.
I don't know, maybe I was something before I became a human and maybe I have a journey ahead of me after this life. Who knows.... reality is all very bizarre. I hope I never forget myself but maybe it would be a relief.