The most common drug for dementia is Aricept or it’s generic. It takes a while to start being effective, then it’s a daily maintenance dosage.
But it only works for a short while & then the inevitable happens.
Biden will be drilled on basic formula answers to predictable questions. He will have reasonably articulate statements to recite on demand. The tell will be that his answers will be ten percent off target and vaguely unresponsive in details which would make a competent answer. They will be ball park boiler-plate with some well practiced attempts at wit but really won’t say anything.