"Not enough people are sounding the alarm that based on his behavior, and in my opinion,
Donald Trump is dangerously demented...
... This is a tale of two brains: Biden's brain is aging, Trump's brain is dementing."
Harry Segal of Cornell University and Weill Cornell Medical School notes that Trump's campaign speeches have been increasingly "erratic."
Segal told Salon, "In the past six months, Trump's rallies are filled with strange lapses of logic. He has confused Biden with (Barack) Obama, spoke of World War 2, and has lapsed into bewildering digressions that are hard to follow. Only this weekend, he said, 'We have languages coming into our country that no one can speak' — a strange grasping for meaning, bordering on neologism. At other times, he seems to get lost in the middle of a sentence..."
Greenwood told Salon, "We all stumble over and mispronounce words occasionally. This is not what is going on with Trump. The incidence of these kinds of mistakes takes him into this realm of phonemic paraphasia, which is a sign of underlying brain damage, not just aging. Even when compared to his speech of a few years ago, you can observe a noticeable difference. When you compare it to his speech as a middle-aged man, the shift is radical and ominous."