Wasn’t Biden diagnosed with or treated for a brain tumor a couple of decades ago? I understand that survivors of brain tumors are never actually free of the symptoms - the surgical or chemical solutions are only temporal. This would explain so much about Joe’s behavior.
Aneurysms.
I play in a band with a guy (Joe) who had a terminal Brain tumor the size of a cue ball. Dr's wouldn't touch it, gave him days to live. He went home, saw a televangelist on tv, touched the screen and is alive and well after twenty years!
Believe me the symptoms still exist, they guy is just not all there, but can play the living daylights out of a keyboard!
In the Keith Emerson, Greg Rollie Ivory Tickling League.