He does have psychological problems, but I suspect there's something going on in his brain and it seems to be getting worse. Somebody competent in such matters needs to have a look.
Well, go and have that look but please, keep letting him gorge on KFC and McDonald's, as much as he wants. Maybe nature will just take its course and he'll vapor lock and just make those spastic gestures and babble like he did on the campaign trail, but because he can no longer do otherwise.
Then they'll have to 25A his dumb ass.