Eyes Glaze Over (EGO)
Everyone has had the experience of reading while distracted, preoccupied or fatigued. The eyes continue to scan the page, the words flow along, but they convey no meaning to the distracted mind and are instantly forgotten. Sometimes it is necessary to go back and re-read a page or two.
Eyes Glaze Over is an unconscious defense against cognitive dissonance. The reader begins to see where the argument is going, and the first sensations of cognitive dissonance set in. This disquietude distracts the reader from the text, and at the same time the ongoing flow of words serves as a distraction from the cognitive dissonance. The reader is ultimately spared understanding the argument (understanding would have caused intense cognitive dissonance).
This is a speculative explanation for a phenomenon I've often encountered: you present a cogent argument, and the response is tangential, irrelevant, or incoherent. It is clear that your argument is not being considered. No language, however plain, can cause your argument to be considered. Every time you try, your interlocutor's eyes glaze over at the critical point.