What is "text blindness"

Text \Text\ (t[e^]kst), n. [F. texte, L. textus, texture, structure, context, fr. texere, textum, to weave, construct, compose; cf. Gr. te`ktwn carpenter, Skr. taksh to cut, carve, make. Cf. Context, Mantle, n., Pretext, Tissue, Toil a snare.]

1. A discourse or composition on which a note or commentary is written; the original words of an author, in distinction from a paraphrase, annotation, or commentary.
   --Chaucer.

2. (O. Eng. Law) The four Gospels, by way of distinction or eminence. [R.]

3. A verse or passage of Scripture, especially one chosen as the subject of a sermon, or in proof of a doctrine.

   How oft, when Paul has served us with a text, Has Epictetus, Plato, Tully, preached!
   --Cowper.

4. Hence, anything chosen as the subject of an argument, literary composition, or the like; topic; theme.

5. A style of writing in large characters; text-hand also, a kind of type used in printing; as, German text.

6. That part of a document (printed or electronic) comprising the words, especially the main body of expository words, in contrast to the illustrations, pictures, charts, tables, or other formatted material which contain graphic elements as a major component.

7. Any communication composed of words.

8. a textbook.

   Text blindness. (Physiol.) See Word blindness, under Word.

   Text letter, a large or capital letter. [Obs.]

   Text pen, a kind of metallic pen used in engrossing, or in writing text-hand.