This is very dangerous: Trump regularly "can't remember what he's said or been told," White House insider says
https://www.newsweek.com/donald-trump-anonymous-white-house-insider-memory-1472661?utm_campaign=NewsweekTwitter&utm_source=Twitter&utm_medium=Social
Dementia is a decline and/or loss of memory, reasoning, judgment, behavior, language and other mental abilities that are not a part of normal aging; it usually progressively worsens over time. ... Early signs and symptoms of dementia may go unrecognized, but the first sign is usually loss of: Short-term memory.