@freemo In the speech referred to he said that Nikki Haley declined 10,000 national guard troops to defend the Capitol on Jan 6. Of course Nancy Pelosi didn't do that either, but Trump frequently claims she did.
Anyway my suspicion as to cause is because a relative developed similar gate and stance and anomia to what Trump has. The cause wasn't determined until she had a noticeable stroke. An MRI showed that she had had several strokes that had not been noticed, but killed small regions of her brain.
Not that it mattered. Colon cancer killed her.
In Trump's case the anomia could be something else entirely. Strokes are probably best case as they are not progressive.