I get like this too. (32m) When I’m describing a movie I want to watch to my partner, or describing a movie I have watched I become almost incoherent. Like if I’m reading the description from rotten tomatoes or the like I can barley say one whole sentence without stuttering. I wonder if it’s because psychologically I’m putting myself on the spot, or my brain is saying “you commanded attention, you want him to be interested in this movie, so now you have to sell it”. That somehow puts me into a tail spin. When I talk about my feelings, it’s coming from a genuine and real place deep inside that’s not incessantly interrupted by anxiety or terror. We already know our thoughts very well, because we live with them and so they naturally seem to come out with more fluidity when we verbalise them. When we are describing a book or movie, we are remembering or replaying something we know is not us, but outside of us. Maybe remembering, replaying or reading while talking is to disruptive to our speech?