A very interesting comparison between the linguistic and speech patterns of Donald Trump in the 80s and 90s and today. The amount of cognizant decay is unmistakeable.

STAT asked experts to compare Trump’s speech from decades ago to that in 2017. All noticed deterioration, which may signal changes in Trump’s brain health.

In interviews Trump gave in the 1980s and 1990s (with Tom Brokaw, David Letterman, Oprah Winfrey, Charlie Rose, and others), he spoke articulately, used sophisticated vocabulary, inserted dependent clauses into his sentences without losing his train of thought, and strung together sentences into a polished paragraph, which — and this is no mean feat — would have scanned just fine in print. This was so even when reporters asked tough questions about, for instance, his divorce, his brush with bankruptcy, and why he doesn’t build housing for working-class Americans.

Trump fluently peppered his answers with words and phrases such as “subsided,” “inclination,” “discredited,” “sparring session,” and “a certain innate intelligence.” He tossed off well-turned sentences such as, “It could have been a contentious route,” and, “These are the only casinos in the United States that are so rated.” He even offered thoughtful, articulate aphorisms: “If you get into what’s missing, you don’t appreciate what you have,” and, “Adversity is a very funny thing.”

Now, Trump’s vocabulary is simpler. He repeats himself over and over, and lurches from one subject to an unrelated one, as in this answer during an interview with the Associated Press last month:

“People want the border wall. My base definitely wants the border wall, my base really wants it — you’ve been to many of the rallies. OK, the thing they want more than anything is the wall. My base, which is a big base; I think my base is 45 percent. You know, it’s funny. The Democrats, they have a big advantage in the Electoral College. Big, big, big advantage. … The Electoral College is very difficult for a Republican to win, and I will tell you, the people want to see it. They want to see the wall.”

Source: Trump used to be more articulate. What could explain the change?