Linguistics researcher reveals how Trump's speech is declining into a 'narrower, harsher and more unhappy' state

Mental health experts have cautioned that President Donald Trump appears to be declining, but Kurt Andersen isn't sure the president has changed all that much.

During a discussion with MSNBC's "Morning Joe," Andersen explained how he researched Trump's speaking style, frequently used words and pattern of phrases to help write a book with Alec Baldwin in the voice of Trump. The author of "the definitive guide to speaking Trump," according to co-host Mika Brzezinski, has compiled the lexicon for The Atlanticon "How to Talk Trump."

National affairs analysts John Heilemann asked about the frequent "tics" some see in Trump increase over time and the need to repeat the same stories over and over again.

"I think he is -- it's not that he's declining in his verbal fluency," Andersen said. "The emotional affect is narrower and harsher and angrier and more unhappy. It wasn't as though he was talking about reciprocal responsibilities that we have with our many allies abroad 30 years ago and now he's just saying 'disgusting and crooked.' But he does, I think, return to his safe words, his favorite words, somewhat more frequently."

"He was never Lin Manuel Miranda," Heilemann joked of the Tony Award-winning wordsmith.

"He was never Lin Manuel Miranda, or an intellectual," Andersen agreed.

He also said that he hoped to uncover the fundamental elements of Trump's dialect, not merely the words and phrases the president uses over and over.

"And you won't hear it tonight," Andersen said, because someone else is writing the speech. "Presumably the periods will come and so-forth. Where, in the real Trump dialect, it's a limited palette of words of familiar adjectives, disgusting, horrible -- positive adjectives like unbelievable and great and fantastic."

He noted the repetitions are what fascinates him the most in Trump's speaking style.

"Where he'll -- just answer a question -- he'll say the same thing three, four, five times within a matter of, I don't know, 50 sometimes, instead of saying 'many' as a qualifier, he'll say 'many, many, many,'" Anderson explained. "So, it really is a patois. It's not normal English, it's Trump English."

Brzezinski remarked that it seems like it isn't exactly "Trump English" so much as it's "limited English."

"He has these special words he returns to again and again and again," Andersen said. "And when he is not speaking off a teleprompter -- tonight, he'll be speak off a teleprompter -- we won't get true Trump."

Watch the discussion below: