The two men expected to face each other in the general election have a combined age of 151, which is one reason why both keep taking digs at each other about mental fitness. In an interview with Sean Hannity Thursday night, President Trump suggested he did not think that Joe Biden could do as well on a cognitive test as he did, and he proceeded to boast about it. “I actually took one very recently when I was—when the radical left was saying, 'Is he all there, is he all there?'" Trump said, per Mediaite. "I proved I was all there because I aced it. I aced the test and he should take the same exact test, a very standard test." Trump added that he impressed the doctors at Walter Reed Medical Center. "They were very surprised,” he said. “They said, 'That’s an unbelievable thing. Rarely does anybody do what you just did.'"
As the Washington Post notes, the last disclosed cognitive test for the president was in January 2018, and that was a fairly basic 10-minute exam in which people are asked to identify animals in pictures and such. It's unclear if Trump took a more recent exam. Biden, for his part, said Thursday that he can't wait to debate Trump, referencing Trump's description of himself as a "stable genius," per NBC News. At 77, Biden is three years older than Trump, and he said in response to a reporter's question last month that he is "constantly" tested for cognitive decline, prompting Hannity and other Trump allies to wonder why Biden felt it was necessary to be tested so much, per Fox News. “Look, all you gotta do is watch me, and I can hardly wait to compare my cognitive capability to the cognitive capability of the man I’m running against,” Biden said at the time. (Read more President Trump stories.)